Stimulating rumen
Modifying methane production fermentative efficiency

Table 5.1: Effects of ionophores (feed additives) on cattle performance in the USA
(Chalupa, 1988)

Performance (% of control)

Tonophore Diet trials Intake Gain Intake/Gain

Monensin Feedlot 19 94 102 92
Feedlot 6 95 99 95

Pasture 12 - 117 -

Greenchop 3 98 123 85

High forage 12 97 114 91

Lasalocid Feedlot 16 96 103 94
High forage 6 96 105 93

Salinomycin Feedlot 98 106 90

5.1.2 Chemicals reducing methane emissions

Commercial enterprise has been motivated to produce chemicals with properties
for propionate enhancement or methane inhibition in the rumen, because of the
increased efficiency of feed utilisation improved the economics of feedlotting (even
though this is quite small), The results on ruminant performance when some
chemicals are fed in the diet are shown in Table 5.1. As can be seen from this table,
by the addition of such chemical manipulators to a ruminant diet productivity is
increased and as a consequence methane generation is reduced.

There is at least an indication that with halogenated compounds such as
chloral hydrate that methane inhibition can be almost complete. However, while
not yet completely understood, it appears that their action is not sustained: the
microbes may adapt to the compound (See Chalupa, 1988).



Executive summary Tables and Figures

2.11 Tables and Figures

21





Modifying methane production

Improved animal production rate

and methane production

Figure 5.2: Schematic relationship between diet quality (metabolisable energy
MJ/kg dry matter) and food conversion efficiency (g liveweight gain/MJ ME)
(- - -) (from Webster, 1989). The relationships found in practice with cattle fed
on straw or ammoniated straw or poor quality hay with increasing level of sup-
plementation of protein meals that bypass rumen fermentation. Australia (©, 0,
e) (Perdoket al., 1988); (@, A) (Hennessy et al. (1983); Hennessy et al., 1989),
Thailand (A) (Wanapat et al., 1986) and Bangladesh (GQ) (Saadullah, 1984) This
illustrates the marked differences that result when supplements high in protein are

given to cattle on diets of low ME/kg DM

al I
c 1 1
oN i 4
oo 81 vc
aX 3! eae I
lo t
Se bi Le ‘
= ad
‘oul Bz 7 ot H
>= 7 t |
82 a
oS 1 Fl
OD 1 t
Ee 1 t
ti \ 1
1 i=

T T T T T 7

7 9 10 11 12 = 13

(Md/kg)

64

Energy value of diet M/D



Strategic supplementation
of cattle and buffaloes in India The use of bypass proteins in India

Figure 6.1: Colour plates to illustrate the ingredients of the molasses urea blocks,
the manufacturing plant, block in slab form and ready for sale (Kunju, 1989)

1. Ingredients with their % content in the block:
a.cottonseed meal (10%), b.salt (8%), c.mineral mix (15%),
d.bentonite (3%), e.calcite powder (4%) furea (15%),

" molasses 45%
2. Block as manufactured. 3. Packaged block for sale.

15



Part 2

Executive summary

2.1 Introduction

It is well documented that the global atmospheric abundance of methane is in-
creasing. Recent rates of increase are of the order of one percent per year. Based
on analysis of ice core data, it has been estimated that the increase in methane
concentrations began about 200 to 300 years ago. The major anthropogenic
sources of methane emissions are: animals (primarily managed ruminant live-
stock); rice cultivation; biomass burning; oil and gas production and distribution;
coal mining; landfills; and waste management.

The increased abundance of methane will have important impacts on: the
stratospheric ozone layer; background levels of tropospheric (i.e., ground-level)
ozone; global climate. Estimates are that methane will contribute about 20 per-
cent of the expected global warming from the greenhouse effect, second only to
carbon dioxide.

As part of international efforts to address global warming, emissions in-
ventories are being prepared and opportunities for reducing methane emissions
are being identified and evaluated by the U.S. Environmental Protection Agency
and others. A recent workshop sponsored by the Intergovernmental Panel on
Climate Change (IPCC) found that opportunities exist to reduce methane emis-
sions from managed ruminant livestock. Achieving such reductions in concert
with reductions from other key sources could help to stabilize global methane

11



Strategic supplementation
Modifying methane production and the target groups

Table 5.2: Milk yield corrected to 4% fat (i.e., FCM) and liveweight change (LWt)
are shown together with the requirements for bypass protein (BP) and metabolis-
able energy (ME) in relation to their availabilities from the feed.

Lwt Milk MUB Supplem. BP (kg/d) ME (MJ)
change yield intake intake = a
(kg/d) FOM (kg/d) (kg/d) (kg/d) Req’(a) Avail"*(b)b- Req (a) Avail (b)~b
A loes

0.03 5.2 0.44 0 0.19 0.01 0.07 75 370.49
0.14 6.6 0.33 1 0.43 0.20 0.46 88 48 (0.55
0.27 7.3 0.28 2 0.48 0.41 0.85 96 590.61
0.28 17 0.27 3 0.50 0.61 1.22 100 71) (0.71
0.38 1.3 0.24 4 0.52 0.80 1.54 100 84 (0.84
B. Cows

-0.11 5.5 0.58 0 0.19 0.02 0.11 71 38 = 0.53
-0.13 7.5 0.39 1 0.28 0.20 0.71 84 470.56
0.16 78 0.36 2 0.48 0.41 0.85 96 58 0.60
0.29 8.5 0.46 3 0.53 0.61 1.15 105 71 = (0.68
0.09 8.0 0.31 4 0.52 0.80 1.54 100 84 0.84

* Required according to NRC feeding standards
** Availability calculated assuming that rice straw has ME content (M/D in MJ/kg
DM) of 5, the protein concentrate M/D 11.5 and the MUB M/D 5.

2. Cattle in the developed or industrialised countries:
@ fed agro-industrial byproducts (e.g. molasses, sugar beet pulp or
pineapple waste)

¢ fed relatively low-protein grain based diets in feed lots (e.g. sorghum
and whole maize cobs)

© grazing relatively poor pastures in semi arid grazing areas (e.g. parts

of the Southern United States and Northern Australia)



Part 3
Introduction

Part 3 outline: Information is given which relates to the roles of livestock and
the systems of livestock prodaction practised in developing countries and in
India in particular.

The problems of low productivity of ruminants and its consequences for
methane generation are discussed. Strategies for improving productivity from
the available feed resource are outlined.

The future possibilities for integrated farming are discussed in general terms.

The overall strategy for limiting methane generation through strategic man-
agement is outlined. .

3.1 The problem

The level of methane in the Earth’s atmosphere is defined by emissions, from
natural and anthropogenic sources, and natural destruction processes. It is well
documented that the atmospheric abundance of methane is currently increasing
at a rate of about one percent per year. Based on analyses of air trapped in
the ice sheets of Greenland and Antarctica, long term methane trends have been
established. The data indicate that the abundance of atmospheric methane has
increased primarily in the last 200 or 300 years, with relatively stable levels prior
to that time at about one-half the current levels.



Application of strategic
supplementation: some Cash flow of small farmers
important considerations and purchase of supplements

8.9 Cash flow of small farmers
and purchase of supplements

Undoubtedly, in most developing countries MUB and bypass protein should be
fed to ruminants from an early age through their productive life. The most
economic responses will be to an improvement in reproduction. To achieve this,
there will need to be incentives to farmers. These could be of the form of a no/low
interest rate loan, repaid when the animal.is marketed, or free distribution of feed
with a tax at the sale of the product. A priority in such a situation would be
provision of insurance against death of an animal. This is important, particularly
for promotion of potentially high yielding milch animals, as without insurance
the high cost of acquisition makes the proposition of owning an animal often too
risky. The death of an animal may mean financial ruin and even starvation for
the family. Again, insurance of farm animals is being done at the village level in
India.

8.10 Government subsidies

The question of subsidies is a difficult one. At present in India through the co-
operative, the feeds are provided at a no profit/no loss basis and the price of
commodities fluctuate according to demand and availability. The large purchas-
ing power of the feed mills limit price fluctuations. There is a need to consider long
term, low interest rate loans for both the purchase of animals and supplements—a
practice already being applied for the purchase of milch animals in India. The
use of supplements for raising bullocks and meat animals can only be promoted
slowly with education. Initially, farmers will have to be convinced by demon-
stration trials and perhaps provision of supplements that are subsidised for 1-2
years.



Improving ruminant production
Introduction - a in developing countries

e Feed required for high levels of milk production using temperate countries’
feeding systems (over 8000 litres per lactation) is in competition with food
for humans and feed for pigs, poultry and fish. New methods of feeding
are, however, overcoming this and with byproduct protein meals and mo-
lasses/urea blocks, milk yields from Friesian cows and their crosses with
local breeds may approach 5-7,000 litres/305 days lactation.

High levels of milk production from the specialised dairy breeds require
much higher levels of management in the humid tropics than in temperate
countries. Without appropriate feeding strategies and disease control, tem-
perate dairy animals, when introduced into the tropics, often fail to produce
and often have quite short lives.

Milk production in India based on cows with high genetic potential
would need a massive breeding programme and importation strategy to
achieve the numbers needed to supply the milk requirements of a country.
However, using artificial insemination with semen from bulls with high ge-
netic potential, crossbreeding for milk production is a viable option and the
resultant male offspring may be used as draft animals.

The progeny of such crossbreeding have excellent dual purpose char-
acteristics so long as they are given high protein supplements (i.e., balanced
diets) in early life. Cows yield 1500-2000 litres of milk with selected an-
imals often reaching 4000-5000 litres of milk per lactation, which can be
supported on locally available basal feeds such as straw/protein meals and

their meat production potential is comparable to that of the specialised beef
breeds.

Poor nutrition, disease and parasites usually exert a major limiting influence
on animals of high genetic potential and this highlights the importance of combin-
ing appropriate genotypes with relevant management and nutritional strategies
in developing livestock systems suited to given situations.

3.5.1 Impact of climate on production of ruminants

In the humid tropics where night temperatures often remain above 30°C, it is
difficult for ruminants to lose the heat produced when on the feeding levels re-
quired for extremely high yielding cows in temperate climates (that is above 35

35



Stimulating animal production rate

5.2 Stimulating animal production rate

Increased production per animal and turnoff at an earlier age will have a much
greater effect on total methane production than reduction of methanogenesis in-
digestion of individual animals (see Section 5.3). It is imperative that productivity
per animal is stimulated by all means possible to eventually approach genetic
potential. However, where individual animal production rates are increased it
will be essential that animal numbers are decreased in order to realise the large
decrease that can be achieved in methane production. This presupposes that
human requirement for animal products (or the market requirements) can be
saturated.

5.2.1 General
Animal production rate is a composite of a number of functions and includes:

© age at puberty
© reproductive rate and between pregnancies interval
@ survival rate

« growth rate, milk production etc.
Methods for increasing production from roughage based diets include:

¢ supplementation to ensure an active and efficient fermentative digestion

e supplementation to increase the efficiency of nutrient utilisation of the basal
forage -

° supplementation to provide nutrients for milk production in a total bypass
form

© treatment of forage to improve its digestibility

¢ manipulation of the rumen to ensure high digestibility and a high microbial
growth efficiency.

60



Livestock production systems:
comparison between industrialised
Introduction and developing countries

In the rural areas (particularly Africa), cattle are often an important source
of cash income and provide financial security for their owners. They are a capital
reserve in societies where grazing land is communally owned.

A proportion of the people in any developing country have equivalent pur-
chasing power to that of the middle class in industrialised countries. This repre-
sents, for example, some 80 million people in India who can afford to purchase
primary products and are increasingly demanding meat as well as milk.

It can be expected that, with improving standards of living and also with
population density increases, the demand for meat and milk per capita in devel-
oping countries will increase, particularly as most developing countries have large
and increasing populations.

Where institutional credit is restricted, livestock are often a key element in
any critical increase in the cash flow of most small farmers. The sale of livestock
products, in particular milk and meat, provides a major source of disposable
funds for agricultural development (e.g. for purchase of improved seeds and
fertilisers) particularly in India. The first step in improving the standard of living
of smallholder farmers is frequently through an increase in animal productivity.

Milk is often the main source of a number of essential amino acids that are
at times in low supply in the diet of the rural poor, who are often vegetarian
from choice or because they are too poor to purchase animal products. Devel-
opment strategies to improve the standard of living of the rural poor must aim
at increasing the productivity of animals from the available feed resources. This
must be considered when discussing the potential for reducing methane emissions
from cattle in developing countries.

3.3 Livestock production systems:
comparison between industrialised
and developing countries

The high levels of individual animal productivity in the industrialised coun-
tries have been achieved through a disproportionate use of the world’s resources
(Borgstrom, 1980), especially fossil fuels, marine fisheries and the protein rich

31



Improved animal production rate
Modifying methane production and methane production

Unfortunately, despite the widely reported effects on cattle productivity of
treating crop residues to increase their digestibility, even with the support of well-
funded aide programs, there has been a total lack of acceptance of this technology
by small farmers in developing countries. The reasons for this are many and
varied, but it appears that there is no probability of wide-spread application of
straw treatment.

5.3 Improved animal production rate
and methane production

5.3.1 Growth rate and methane generation

Improvements in the efficiency of utilisation of metabolisable energy through
supplementation of poor quality forage based diets fed to ruminants have been
remarkably high. The results of experiments with cattle in which straw or straw
treated to improve its digestibility have been supplemented with protein meals
indicate that the traditional approach of predicting animal production from ME
content of a feed (i.e, M/D in MJ/kg feed) has been highly misleading (this is not
accepted by some scientists). This is illustrated when idealised growth efficiency
(g gain/MJ ME intake) is related to ME content of a feed (Figure 5.2). The
data generated in trials examining response relationships for cattle fed straw and
supplemented with protein meals are also shown in the same figure. The latter
trials were carried out in hot climates whereas the traditional model depicted in
the figure is based on research in temperate countries.

The differences in efficiency of animal growth between the temperate coun-
try standards and the results obtained in practice where cattle fed straw have
been supplemented with protein are due either to a lower demand to oxidise
nutrients for maintenance of body temperature by cattle in the tropics or the
“metabolisable energy system” has not recognised a large heat increment in the
estimates of basal heat production (see Leng, 19896).

Taking these data for production of cattle on straw based diets, some esti-
mates of the likely reduction in methane production in response to supplementa-
tion can be calculated from the model given earlier.

63



Part 9

References

Baldwin, R.L. (1970). Energy metabolism in anaerobes. American Journal of
Clinical Nutrition 28: 1508-1513.

Bauchop, T. (1981). The anaerobic fungi in rumen fibre digestion. Agriculture
and Environment 6: 339-348.

Ben-Ghedalia, D., Est, M.Y. & Yosef, E. (1988). SO. treatment for con-
verting straw into a concentrate-like feed: a growth study with lambs. An-
imal Feed Science Technology 19: 219-229.

Bird, S.H. & Leng, R.A. (1984). Absence of protozoa in the rumen and pro-
duction of grazing sheep. Proceedings of the Australian Society of Animal
Production 15: 654.

Boniface, A.M., Murray, R.M. & Hogan, J.P. (1986). Optimum level of
ammonia in the rumen liquor of cattle fed tropical pasture hay. Proceedings
of the Australian Society of Animal Production 16: 151-154

Borgstrom, G. (1980). The need for appropriate animal production systems for
the tropics. In: Animal Production Systems for the Tropics, Publication
No. 8. International Foundation for Science, Stockholm.

Chalupa, W. (1980). Chemical control of rumen microbial metabolism. In:
Digestive Physiology and Metabolism in the Ruminant, pp. 325-347 [Y.
Ruckebusch and P. Thivend, editors]. Lancaster: MTP Press.

100



Introduction ; The overall strategy

increased animal numbers rather than increased milk production per animal. This
is the opposite of what has happened in developed countries, where the numbers of
dairy animals have decreased and production per animal has improved to provide
the milk requirements of a country.

Operation Flood, a development project in India managed by the National
Dairy Development Board, has been responsible for implementing policies result-
ing in large increases in milk production per animal through better feeding and
breeding. By providing the infrastructure for marketing milk and milk products,
it has set the example for the way forward for most developing countries.

The large increase over the last 10 years in importation of animal products
into the underdeveloped sections of Africa has resulted from increasing demand.
There is therefore the stimulus for these countries to increase production per
animal as they cannot afford these imports. Imports of meat and milk into Africa
have risen seven fold on a per caput basis, and in 1979 cost close to $US5 billion
per year (Brumby, P., ILCA statistics). On the other hand India needs only to
import milk products when drought conditions effect large tracts of country

Tn the future there must be large increases in the demand for animal prod-
ucts in all developing countries. If this is achieved by increasing animal numbers,
rather than increasing individual animal productivity then large ruminants will
continue to contribute significantly to the global methane emissions. It is essential
that the increased demand for primary products be met from increased animal
productivity without utilising resources directly usable by the human population.
The demand must also be.met from fewer animals growing and reproducing at
much higher rates than presently attained.

3.8 ‘The overall strategy

The bottom line is that strategies must be developed that maximise animal pro-
duction from the available resources and minimise the numbers of ruminants
needed to meet a country’s need for:

e milk, meat and other animal products
e draft power.



Strategic supplementation Case study: application
of cattle and buffaloes in India of strategic supplementation

Figure 6.5: Age at first calving of cows of different breeds fed tropical forages
and supplemented with bypass protein and MUB according to their needs (NDDB
report—Sabarmati Ashram Gaushala, 1987). Kankrej is a local cattle breed (Bos

indicus)

6 Age at first calving (months)
56

557
50-4
454
40+
354+
32

304
26.5 26.8

264

2075

164

10+

54

Jersey Cross-bred Kankrej Holstein Friesian

83



Improved animal production rate and methane production ... .
5.3.1 Growth rate and methane generation ......... tae
5.3.2 Milk production and methane generation. .........
5.4 Strategic supplementation and the target groups. .........
5.5 Conclusion... 6... 2. ee ee ee eee eee

Strategic supplementation of cattle and buffaloes in India

~ 6.1 Introduction... .....0....006 eee eee eee

6.2 Molasses/multi-nutrient blocks... ..........0000006
6.3 The use of bypass proteins in India .............200-
6.3.1 Research with bypass protein ............0000-
6.3.2 Dairy husbandry activities... 0... ee
64 Conclusion. 2.2... ce ee ee teens

6.5 Case study: application of strategic supplementation .......

Consequences of widespread application of feeding
and breeding in India

7.1 Milk production. 2.0... . eee ee ee eee oe
7.2 Effects on reproduction rate ©... 0... ee ee ees
7.3 Milk production and draft power .........2.2000005
7.4 Draft power—body size... eee
7.5 Population densities of dairy animals ........-.......-

7.6 Overall conclusions ............65 bee ee eee

69
69
71

72
73
73
14
14
78
82
82

90

7.6.1 Methane production by cattle fed high v. low quality forages 91



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Strategies for improving
animal production/reducing
Introduction greenhouse gas emissions

3.6.1 Management to increase ruminant productivity

For most systems, improved reproduction rates of cattle (which are extremely
low on pasture or crop residue based feeding systems) will be the critical issue.
Improvement in a feeding strategy will improve reproduction. Improved nutrition
and reproduction rates are compatible with improvements in the genetic base.

In terms of management the most critical areas to improve production rate
of cattle are:

e improved nutrition;

@ disease and parasite control;

© improved animal genotype to take advantage of the improved management;

¢ improved animal growth leading to larger animals with greater draft capa-
bilities;

© improved implements for draft animals, reducing the numbers of draft ani-
mals required. :

3.6.2 Integrated farming systems

As fuel requirements are often difficult to meet in many developing countries
even for household needs, the use of feces directly as fuel or to generate biogas is
a useful and important factor in any strategy—particularly in India, Africa and
other parts of Asia where the availability of fuel is a major problem (MacNamara,
1985). Integrated farming systems may have a major role to play in the future
in decreasing emissions of carbon dioxide and methane and therefore mention is
made of it here.

The principles for achieving optimum resource use include:
e development of livestock production systems that match available resources
and thus use these resources efficiently

e selection of crops and cropping systems that maximise biomass production
and therefore carbon dioxide and nitrogen fixation

38



Strategic supplementation
Modifying methane production and the target groups

5.3.2 Milk production and methane generation

Recent research by Kunju (1990) has shown that when strategic supplements are
provided to lactating animals, a marked increase in the efficiency of conversion
of feed to milk is also apparent. This research, carried out in India, clearly
suggests that at low levels of milk production the requirements for metabolisable
energy and hence feed are reduced when the feeding strategy emphasises the
balanced nutrient approach. Milk was produced at 16-50% of the feed costs
accepted under traditional feeding methods. The results of a trial to establish
response relationships to feeding protein concentrate to lactating animals is shown
in Table 5.2.

Methane production per litre of milk can be calculated using some rules of
thumb. In the calculations made in this presentation the feed conversion to milk
is calculated from the feed required to grow the animals to first lactation and the
feed utilised in its adult life. The calculated data are shown in Figure 5.6.

5.4 Strategic supplementation
and the target groups

A total supplementation package consisting of a multinutrient block plus a by-
pass protein feed needs to be applied to ruminants fed relatively poor quality
forages/pastures.

The target groups of large ruminants for this strategy include the following:

1. Cattle/buffalo in developing countries:

© fed crop residues or cut/carry grass and agro-industrial byproducts

@ grazing in areas with monsoonal climates in the tropics, particularly
in the dry season

grazing tropical grasslands on infertile soils (e.g. Los Llanos, Colombia;
Brazil and the Pampas, in Argentina)



Strategic supplementation
of cattle and buffaloes in India The use of bypass proteins in India

Figure 6.3: Effects of increasing supplement levels (fish meal—a recognised bypass
protein) on milk yield of cows fed ammoniated straw (i.e., treated to increase

digestibility) (Saadullah, 1984) ;
1

Milk yield (kg/day)

4

8 100 200 300 400
Fish meal (g/day)

6.3.2 Dairy husbandry activities

The improved production that can be achieved by superior feeding and breeding
can be seen by recent practical results of feeding trials conducted on one of the
farms managed by the NDDB of India (Sabramati Ashram Gaushala, which was
founded in 1915 by Mahatma Gandhi as part of the Haryan Ashram at Ahmed-
abad.) The major aim of the Gaushala, besides multiplication of high yielding
milch animals, is to enhance the productivity of land and milch animals by har-
nessing the latest technologies in the field of animal husbandry and agriculture.

The Gaushala has had a herd of Jerseys and has been cross breeding these
with the local breed—Kankrej (Zebu), and more recently has introduced Holstein-
Friesians from Germany.

The dairy animals are zero-grazed and fed on a good quality green fodder,
hay, silage and rice straw depending on season. These animals are also fed a
‘bypass protein meal’ proportionate to their body weight, growth potential, preg-
nancy status and milk production. A molasses/urea multinutrient block is always
available and experience suggests that the cattle only use this when they need
extra non-protein nitrogen. Diseases are controlled by vaccination and the herd
is free of Tuberculosis, Johne’s disease and Brucellosis. A regular culling of poor
quality animals or low productive animals is carried out.

18



United States Air and EPA/400/1-91/004
Environmental Protection Radiation June 1991
Agency (ANR-445)

SEPA Improving Ruminant Production
And Reducing Methane

_.. 4Emissions.From Ruminants

_ ~~. By Strategic Supplementation

EPA
400/
1-
91/004
c.2

St Printed on Recycled Paper



References

Small Ruminant Productivity in Semi-arid Areas, pp. 81-91 [E.F. Thomson
and F.S. Thomson, editors]. Syria: ICARDA. 81-91.

Porter, G. (1983). Food and energy: interdependent world needs. In:. Chem- -
istry and world food supplies: the new frontiers, [ G. Bixler and L.W.
Shemilt, editors]. Manila, the Philippines: IRRI. ‘

Preston, T.R. (1989). . Inexpensive: biogas digestors. Published by CIPAV,
Calle 8a, No. 3-14 Piso 17, Apartado. Aereo 7482, Cali, Colombia.

Preston, T.R. & Leng, R.A. (1984). Supplementation of diets based on fi-
brous residues and byproducts. In: Straw and other fibrous byproducts as
feed, pp. 373-413 [F. Sundstgl and E. Owen, editors]. Amsterdam: Else-

vier. :

Preston, T.R. & Leng, R.A. (1987). Matching Ruminant Production Sys-
tems with Available Resources in the Tropics and Subtropics. Armidale,
Australia: Penambul Books.

Ramjee, R., Boodoo, A.A., Dolberg, F. & Rowe, J.B. (1988). Performance
of calves and milk production of cows under village conditions. In: Milk
and Beef Production in Mauritius, pp. 29-32 [Boodoo, A.A., Ma Poon,
L.K., Rajkomar, B., Rowe, J.B., Dolberg, F. and Hullman, B., editors].

Saadullah, M. (1984). Studies on utilization of rice straw by cattle. Ph.D.
Thesis, Royal Veterinary University, Copenhagen.

Soetanto, H. (1986). Studies on the role of rumen anaerobic fungi and protozoa
in fibre digestion. M.Rur.Sc. Thesis, University of New England, Armidale,
Australia.

Sundstgl, F. & Owen, E.C. [editors] (1984). Straw and other fibrous by-products
as feed. Amsterdam: Elsevier.

Ushida, K., Jouany, J.P., Kayouli, C. & Demeyer, D.I. (1989) Effect of de-
faunation on fibre digestion in sheep fed NHy-treated straw based diets. In:
The Roles of Protozoa and Fungi in Ruminant Digestion, [J.V. Nolan, R.A.
Leng and D.I. Demeyer, editors]. Armidale, Australia: Penambul Books.

104





References

Walker, B. (1987). Animal production from pasture and forages in the trop-
ics. In: Proceedings of the 4th AAAP Annual Science Congress pp. 5-8
[T.F. Reardon, J.L. Adam, A.G. Campbell and R.M.W. Sumner, editors.
Hamilton, New Zealand.

‘Wanapat, M., Duangchan, S., Pongpairote, S., Anakewit, T.
& Tongpanung, P. (1986). Effects of various levels of concentrate fed with
urea-treated rice straw for purebred American Brahman yearling cattle. In:
Ruminant Feeding Systems Utilizing Fibrous Agricultural Residues—1985,
Proceedings of the 5th Annual Workshop of the Australian-Asian Fibrous
Agricultural Residues Research Network. pp. 149-153 [R.W. Dixon, editor]
Canberra: IDP.

Webster, A.J.F. (1989). Bioenergetics, bioengineering and growth. Animal
Production 48: 249-269.

105



Executive summary

Tables and Figurés

Figure 6: this appears later as Figure 6.6

A case study of the implementation of feeding strategies for large ruminants based
on bypass protein (commencing Dec Ist, 1988) (NDDB records). In the Kiara dis-
trict, Anand, India, there are some 18,000 crossbred cows (70% in milk), 55,000
indigenous cows (55% in milk) and 350,000 buffaloes (40% in milk) (Kunju,
1989).

(A) shows the sales of a supplement-feed in the district from the Amul Feed
Mill when a so-called balanced concentrate was available (1987/88) and after the
change (1st Dec, 1988) to a 30% protein meal (bypass protein). In the latter
system, the recommendations are to feed a molasses/urea block and half the pre-
vious quantity of supplement. Initially, there was some stockpiling of the original
feed and there was marked resistance by farmers to the new feed. This resistance
subsided.

(B) shows the milk procurement at the Amul Dairy Factory over the same three
years.

(C) shows that farmers have faithfully followed instructions and that the rate of
supplement (high protein feed) used, has dropped to about 950 g/litre of milk as
compared to 700-800 g/litre of milk on the traditional concentrate. Milk yield has
increased from 1.25 I/kg (old supplement) to 2.8 V/kg (new supplement).

(D) shows the thermal humidity index for Bombay. This is an indez of the relative
heat stress. Above 72 milk production is adversely affected in cattle fed on high
quality feeds.

See nezt page.



Strategic supplementation Case study: application
of cattle and buffaloes in India of strategic supplementation

. Supplements sold (‘000 MT/month) Milk procured at Amul (‘000 MT/month)
34

-@ 1980/87 -4- 1987/88 -O- 1988/89 ~*- 1989/00 32

A

-& 1988/87 -4- 1987/88 «= ~@ 1988/80 —* 1989/90

a
a\

8. 10.
Oec van Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov

as Milk/supplement (litres/kg) 100 THI - Bombay (Celsius)

-@ weeve7 -O- 1987/88 = -O-1988/80 © 1999/00

05. 50.
Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mer Apr May Jun Jul Aug Sep Oct Nov



Strategic supplementation
of cattle and buffaloes in India The use of bypass proteins in India

Table 6.3: A comparison of liveweight change of cattle ($20 kg) when given treated
or untreated rice straw plus molasses/urea block (15% urea) to supply fermentable-
nitrogen and with 0.6 kg rice pollard to supply small amounts of starch and lipid
and various levels of a bypass protein meal (Perdok et al., 1988)

Supplement

Straw preparation (protein meal) (kg/d) Growth rate (g/d)
None 0 38

0.4 365

0.8 292

1.2 306
Treated with 3% NHg gas 0 236

0.4 497

0.8 601

1.2 639

The point is that with these management strategies, milk production, age
at first calving and reproductive rate have equalled those of cattle in developed
countries, but using only forage based diets supplemented according to the prin-
ciples explained by Preston & Leng (1987) ie. molasses urea blocks and high
bypass protein (30% CP) meals based on oilseed meal residues and rice pollard.

Virtually no grain is fed (only 10% grain is included in the bypass protein to
promote a ‘good’ pellet). Yields of milk from the two pure breeds and the cross-
breds are shown in Figure 6.4. The average milk yield of the recently introduced
Friesians in their first 305 day lactation is around 5000 litres/300 d.

80



List of Tables

3.1

3.2

3.3
3.4

41

5.1

5.2

6.1

6.2

6.3

FAO statistics for livestock populations in Asia/Pacific region as
Cs rr

Average meat production (kg) per animal of total population of
cattle/buffaloes in Europe and in Asia/Pacific (1986) .......

Average carcass weight (kg) per animal slaughtered (1986) ... .

Average milk produced (litres/lactation) per total population or
per animal milked (1986)... ............0020000.8

Effect of different efficiencies of microbial growth on ratio of protein
to VFA energy available to ruminants... ..........00.-

Effects of ionophores (feed additives) on cattle performance in the
USA oe ee ee

Milk yield and liveweight change are shown together with the re-
quirements for bypass protein and metabolisable energy in relation
to their availabilities from the feed... 0... 6... ee eee

Intake of rice straw and growth rate of Jersey bulls given concen-

trate with or without access to a urea/molasses block... ... .

Milk and milk fat sales per buffalo before and after the introduction
of molasses/urea blocks into villages .......-.0000006

Comparison of cattle body weight change when given treated or
untreated rice straw plus molasses/urea block and rice pollard . .

8

80


Digestive physiology of
ruminants: implications for

improving animal production

from poor quality forages A model of fermentation in the rumen

Table 4.1: The effect of different efficiencies of microbial growth on ratio of pro-
tein to VFA energy available to ruminants

Protein

Microbial VFA Methane Heat VFA energy
Yarp protein (g) energy (MJ) energy (MJ) energy (MJ)  (g protein/MJ)

8 498 55.5 9.4 64 9
14 798 46.8 8.5 5.1 17
19 1008 40.8 8.0 4.3 24
25 1212 34.9 7.6 3.1 34

Example is for a steer consuming 4 kg fermented organic matter (Leng, 1982a)

In the stoichiometry, Hz indicates reduced co-enzymes, HAc is acetic acid.
HPro is propionic acid and HBu is butyric acid

e that the production rates of individual volatile fatty acids are proportional
to their concentrations (Leng & Brett, 1966) -

e that one-third of the organic matter fermented is converted to microbial
cells

e that the moles ATP generated per mole of end-product are for acetate 2,
butyrate 3, propionate 3, and methane 1 (Isaacson et al., 1975).

The equation relating substrate and products for fermentation of 4 kg of
carbohydrate is as follows:

16.7CHO —- 21HAc + 6HPro + 3HBu + 7.5CH, + 78ATP
8.3CHO —+ 1.4 polysaccharide + 13.8 pyruvate + 2CH, + 17ATP
Overall: :

25CHO —> 21HAc + 6Pro + 3HBu + 9.5CH, + 1300 g dry cells

50



Part 8

Application of strategic
supplementation: some
important considerations

Part 8 outline: Application of the feeding strategies must consider socio-
economic aspects and also the local availability of resources, particularly protein
meals.

The future, probably, lies, for most countries and districts, in developing a by-
pass protein concentrate from locally available protein meals. Some approaches
to this are indicated. In most developing countries there will be a need to de-
velop the facilities (for feed manufacture) and markets for products.

Most importantly the need for education in the new feeding strategies is em-
Phasised. This is particularly important for the farmer, the extension worker
and the University graduate.

8.1 Introduction

Both large and small ruminants in developing countries are owned in small herds
by farmers. The large numbers of farmers presents an enormous problem in
applying any technology for improving productivity by supplementation.

92



Modifying methane production

5.5 Conclusion

The technology for improved animal production on low quality feeds is available,
the resources for implementation of new nutritional strategies are also usually
available. However, there is a long time lag in acceptable. This time-lag is
largely due to institutional, political and sociological constraints and these are the
major limitations which are preventing their application to increasing livestock
production in developing countries.

It is possible that even in developed (temperate) country conditions, widespread
use of protein supplements may allow a reduction in the dependence on grain
based concentrates or even increase production levels where these are below the
average for a country and so reduce methane production per unit of product.



Introduction Ruminant feed resources in Asia

Table 3.2: Average meat production (kg) per animal of total population of cat-
tle/buffaloes in Europe (representative of the concentrate/forage feeding systems)
and in Asia/Pacific (1986)

Cattle Buffalo

Europe 68 50
Asia/Pacific 5 7

meals. Even if this could be repeated in the developing countries, it would be
a short-sighted one to adopt, since fossil fuels must increase in relative cost as
world reserves become depleted and the environmental crisis increases (Porter,
1983).

The industrialised countries are, for the most part, situated in regions with
temperate climates conducive to the growing of cereals and high protein, high
quality forages. In contrast, the developing countries, are mainly tropical and in
general produce cereals only for human consumption. They have, in the past,
exported protein meals arising from oilseed crops in order to earn foreign ex-
change; the availability of protein meals is now known to hold the key to improved
productivity of livestock fed on the available forage resources (this is discussed
extensively by Preston & Leng, 1987). These protein meals are now less in de-
mand with the development of soyabean production in Europe and, because their
export is decreasing, there'is an increasing availability at local outlets in India.

3.4 Ruminant feed resources in Asia

Ruminants in Asia are mainly supported on byproducts of agriculture and their
growth and production rates are low (Tables 3.2, 3.3 and 3.4) compared to the
averages in developed-temperate countries where improved pastures, grain based
concentrates and high protein forages are fed (e.g. USA, Canada and Europe).

32



Digestive physiology of
ruminants: implications for
improving animal production
from poor quality forages

The rumen

Digestion in the ruminant is different from that in monogastric animals
(e.g. humans and pigs) because of the fermentation of feed in the rumen prior
to acid and alkaline digestion in the intestines. Fermentative digestion results
in major alterations in the type and balance of nutrients available to the animal
when compared to that contained in the feed. Plant cell-wall materials (largely
indigestible by monogastric animal species) can be digested through microbial
fermentation in the rumen and therefore ruminants are often the main source of
animal protein in countries with large resources of crop residues and poor quality
pasture (i.e., from pastoral areas unsuitable for cropping).

4.2 The rumen

The dominant feature of the digestive tract of cattle is the ramen, which maintains
an environment capable of supporting dense and varied populations of micro-
organisms. These organisms ferment carbohydrates and other plant materials to
produce mainly short-chain organic acids or volatile fatty acids (VFAs), methane

and carbon dioxide and the process provides 4 ATP (energy) for the growth of
micro-organisms.

The microbial system in the rumen is anaerobic and includes bacteria, pro-
tozoa and fungi. Over 200 species and strains of organisms have been identified
to date, although on individual diets a smaller number dominate. The complex
rumen ecology includes both competition and cooperation among these organ-
isms which ferment the primary feed constituents (fibre, sugars, and starches)

into secondary products that can be catabolized further and subsequently used
by the animal.

Rumen methanogenic bacteria are the source of methane produced in ru-
minants. Although these bacteria are a small fraction of the total population of
microorganisms in the rumen, they play an important role in the complex rumen
ecology. While methanogens can convert acetate (a fermentation product pro-
duced in the rumen) to methane and carbon dioxide, this pathway for methane
production in the rumen is of minor importance. Instead, the conversion of hydro-
gen or formate and bicarbonate from the fluid medium is the primary mechanism
by which methanogenic bacteria produce methane in the rumen.



Digestive physiology of

ruminants: implications for

improving animal production

from poor quality forages A model of fermentation in the rumen

Figure 4.2: Relationship between the production of microbial cells (Cell DM) and
volatile fatty acids (VFA) and methane (CH,) in fermentative digestion in ru-
minants. The relative efficiency of the system (indicated as Yarp) is governed
largely by the availability of essential nutrients for microorganisms (after Leng,
1982). The ranges of Yarp are shown for:

A. a relatively inefficient rumen (i.e., ammonia deficient)

B. a ‘normal’ rumen with no deficient nutrient for microbial growth

C. a rumen free of protozoa with no deficient nutrient for microbial growth
D. the theoretical optimum microbial growth efficiency

CH4

% of rumen DE in:

4 s 4
hh a ee
ol . Spee gb

< Heat
0 T T T T T T T T T T T T
0 2 4 6 8 10 12 14 16 18 20 22 24 26

Yatp



Digestive physiology of

ruminants: implications for

improving animal production

from poor quality forages Fermentative efficiency in the rumen

The bacteria are the principal organisms that ferment plant cell-wall carbo-
hydrates (Hungate, 1966) but the anaerobic phycomycetous fungi may at times
be extremely important (see Bauchop, 1981).

Protozoa on the other hand are now recognised as having a negative effect
in the rumen, particularly where ruminants are fed on diets low in true-protein
(Bird & Leng, 1984). Protozoa ingest and digest bacteria and reduce the bacterial
biomass in the rumen (Hungate, 1966; Coleman, 1976). They decrease the protein
to energy ratio in the nutrients absorbed (see later) and in this way increase the
requirement of animals for true protein and conversely they decrease the efficiency
of utilisation of feed for growth and milk production (see Bird & Leng, 1984).

The presence of protozoa in the rumen may also reduce the rate at which
bacteria colonise and degrade the ingested feed particles. In studies with sheep fed
straw based diets, it has been found that the apparent digestibility of dry matter
was increased by 18% after protozoa had been removed from the rumen (i..,
defaunated) (Soetanto, 1985; Bird & Leng, 1984), suggesting that large increases
in productivity may be achieved with ruminants fed fibrous diets, particularly
those low in true protein. These changes in digestibility have not been observed
on diets based on straw and grain and in some instances removal of protozoa from
the rumen has led to decreased digestibility of mixed diets (Jouany, 1989).

Rumen methanogenic bacteria are the source of methane produced in rumi-
nants. Although these bacteria are a very small fraction of the total population of
microorganisms in the rumen, they play an important role in the complex rumen
ecology. While methanogens can convert acetate (a fermentation product pro-
duced in the rumen) to methane and carbon dioxide, this pathway for methane
production in the rumen is of minor importance. Instead, the conversion of hydro-
gen or formate and bicarbonate from the fluid medium by the primary mechanism
by which methanogenic bacteria produce methane in the rumen.

4.3  Fermentative efficiency in the rumen

A deficiency of a nutrient needed by the micro-organisms in the rumen will, in
general, reduce the microbial biomass and therefore reduce digestibility and feed
intake, particularly of fibrous feeds. The first priority for feeding ruminants on
any diet must be to ensure the availability of essential nutrients for microbial

45



Strategic supplementation

of cattle and buffaloes in India The use of bypass proteins in India

Table 6.1: Intake of rice straw and growth rate of Jersey bulls (350 kg liveweight)

given 1 kg of concentrate with or without access to a urea/molasses block (see
Kunju, 1986)

Straw Intake of Livewt. Totalfeed Feed costs
intake block change costs per kg gain
(kg/d) (g/d) (g/d) (Rupees/d) (Rupees/kg)

Straw + 1 kg
concentrate 6.4 0 220 2.0 9.3

Straw + Lkg

concentrate
+ block 6.8 530 700 2.6 3.7

a traditional system is around 0.5 litres/day indicating the block-licks corrected a
widespread deficiency of nutrients in the diets normally fed to cattle and buffalo
in village situations. Figure 6.2 illustrates the method of presentation of MUB
to milch animals under village conditions.

6.3. The use of bypass proteins in India

6.3.1 Research with bypass protein

When digestibility of straw is increased by chemical treatment and strategic sup-
plements are given, growth rates of cattle approach the level that is supported
by medium quality pasture; but the efficiency of feed utilisation is much higher
than that of cattle fed unsupplemented hay. The effects of straw treatment and
supplementation are illustrated by the studies presented in Table 6.3 and also
in Figure 5.2. The efficiency of productivity of cattle on straw based diets (g
liveweight gain/MJ ME) supplemented with MUB and a bypass protein feed are
higher than temperate country standards would predict.

14



Strategic supplementation Case study: application
of cattle and buffaloes in India of strategic supplementation

Figure 6.6: A case study of the implementation of feeding strategies for large
ruminants based on bypass protein (commencing Dec Ist, 1988) (NDDB records).
In the Kiara district, Anand, India, there are some 18,000 crossbred cows (70%
in milk), 55,000 indigenous cows (55% in milk) and 350,000 buffaloes (40% in
milk) (Kunju, 1989).

(A) shows the sales of a supplement-feed in the district from the Amul Feed
Mill when a so-called balanced concentrate was available (1987/88) and after the
change (1st Dec, 1988) to a 30% protein meal (bypass protein). In the latter
system, the recommendations are to feed a molasses/urea block and half the pre-
vious quantity of supplement. Initially, there was some stockpiling of the original
feed and there was marked resistance by farmers to the new feed. This resistance
subsided.

(B) shows the milk procurement at the Amul Dairy Factory over the same three
years.

(C) shows that farmers have faithfully followed instructions and that the rate of
supplement (high protein feed) used, has dropped to about 350 g/litre of milk as
compared to 700-800 g/litre of milk on the traditional concentrate. Milk yield has
increased from 1.25 W/kg (old supplement) to 2.8 l/kg (new supplement).

(D) shows the thermal humidity indez for Bombay. This is an index of the relative
heat stress. Above 72 milk production is adversely affected in cattle fed on high
quality feeds.

See nest page.

84



Strategies for improving
animal production/reducing
Introduction. greenhouse gas emissions

© generation of biogas from animal feces and urine

e recycling of inorganic wastes from livestock to minimise fertiliser require-
ments

more efficient use of agricultural by-products and crop residues as sources
of ruminant feeds, or directly for fuel

use of multipurpose animals such as cattle and buffaloes that work and
provide milk and meat and also breed to provide suitable draft animals, in
addition to supplying fuel and fertilizer from their excreta

incorporation into the production system of appropriate non-ruminant species
that are well adapted to tropical feed resources, by-products and wastes (e.g.
ducks, rabbits and fish) and which can use biomass with minimum methane
production (e.g. pigs fed sugarcane juice).

3.6.3 Integration of livestock
with crops/fuel production

The integration of livestock with crop production is a means of establishing sus-
tainable farming systems that aim to optimise resource use and in addition it
will reduce carbon dioxide and methane generation in agricultural systems. The
realisation of such aims will maximise the degree of self-reliance of the system,
since a variety of products will be obtained with minimum inputs to maintain
soil fertility.

The integration of livestock into-agricultural systems based on food crops
calls for efficient use of crop residues and agro-industrial byproducts by the ru-
minant. As is discussed later, the by-products from such crops are inefficiently
used at present, with consequences for environmental pollution.





References

Jasiorowski, H.A. (1988). Perspective and prospective of buffalo breeding for
milk and meat production in the world. In: Proceedings of 2nd World
Buffalo Congress, December 1988, New Delhi, (in press).

Johnson, H.D. (1987). Bioclimates and livestock. In: Bioclimatology and the
Adaptation of Livestock, World Animal Science B5. pp. 3-16 [H.D. John-
son, editor]. Amsterdam: Elsevier.

Jouany, J.P. (1989). Effects of diet on populations of rumen protozoa in rela-
tion to fibre digestion. In: The Roles of Protozoa and Fungi in Ruminant
Digestion, [J.V. Nolan, R.A. Leng and D.I. Demeyer, editors]. Armidale,
Australia: Penambul Books.

Kunju, P.J.G. (1986). Urea molasses block lick: a feed supplement for rumi-
nants. In: Rice Straw and Related Feeds in Ruminant Rations, pp. 261-274
[M.N.M. Ibrahim and J.B. Schiere, editors]. Kandy, Sri Lanka: Proceedings
of Workshop.

Kunju, P.J.G. (1989). Role of urea/molasses blocks and a bypass protein on
rumen fermentation and productivity of cattle and buffalo. M.Rur.Sc Thesis
(submitted). University of New England, Armidale, Australia.

Kurup, M.P.G. (1989). Technological innovations in milk production. Pre-
sented at the International Dairy Conference - Operation Flood III, Anand,
India.

Leng, R.A. (1970). Formation and production of volatile fatty acids in the
rumen. In: Physiology of Digestion and Metabolism in the Ruminant, pp.
406-421 [A.T. Phillipson, editor].

Leng, R.A. (1982a). Modification of rumen fermentation. In: Nutritional Lim-
its to Animal Production from Pastures, pp. 427-453 [J.B. Hacker, editor].
Farnham Royal, U.K: CAB.

Leng, R.A. (19828). A theoretical discussion on the factors limiting production

in cattle fed basal diets of straw. In: Mazimum Livestock Production from
Minimum Land,.pp. 79-104 [T.R. Preston, C.H. Davis, F. Dolberg, H.
Mozammel and M. Saadullah, editors]. Proceedings of the 3rd Seminar
Bangladesh Agricultural Research Institute, Mymensingh, 13-18 Feb., 1982.

102



Modifying methane production Stimulating animal production rate

5.2.3 Treatment of forages to improve digestibility

A variety of physical and chemical treatments can be used to increase the po-
tential rate and extent of degradability of fibrous feeds (see Sundst¢l & Owens,
1986). The principal methods use strong alkalis, of which the most widely stud-
ied is sodium hydroxide. While this chemical is highly effective in increasing di-
gestibility of, for example, straw, the disadvantages (high cost, pollution through
accumulation of sodium ions and the dangers to people and animals due to its
corrosive nature) do not allow it to be applied in developing countries. It can
be economic for the treatment of bagasse (the fibrous by-product of sugarcane)
to produce a cattle feed, where bagasse has a negative economic value because it
has to be disposed of from the sugar mills.

There has been much greater acceptance of the use of ammonia to treat
and improve straw utilisation by ruminants. Ammonia can be used as gas, as
ammonium hydroxide solution, or by generation from urea by bacterial activity
during the ensiling of straw at high moisture content.

Hydrochloric acid (especially in gaseous form) and sulfuric acid or sulfur
dioxide have also proved to be effective chemicals for treating straw to improve its
digestibility. Sulfur dioxide combined with ammonia appears to be the treatment
that has most potential for increasing digestibility of straw and has been used
with high pressure steam to take straw digestibility up to 80-90% (Ben Ghadalia
et al.,1988). However, feed intake is reduced by excessive amounts of sulfur. The
use of gaseous ammonia and sulfur dioxide could have advantages where high
feed intakes are not desired e.g., when cattle and sheep are on sub-maintenance
feeding or under drought conditions.

A novel method of using acid hydrolysis is through high-pressure steam
treatment, especially with agro-industrial byproducts such as bagasse. Steam at
high temperature liberates acetic acid, which hydrolyses the lignin-carbohydrate
linkages. The technology has only limited application, for example as in sugar
mills, where high pressure steam is usually available at little cost and where the
bagasse is also produced and must be disposed of without pollution. As indicated
in Figure 5.2, treatment of low digestibility forages improves the rate of animal
production, particularly when strategic supplements are also given (Perdok et al.,
1988; Wanapat et al., 1986) (see also Table 6.3).

62



Digestive physiology of
raminants: implications for

improving animal production .
from poor quality forages A model of fermentation in the rumen

Figure 4.1: Relationship between carbohydrate (polymers) fermentation and the
production of VFA, methane and carbon dioxide and microbial cell synthesis

CH20. NHg, AMINO ACIDS

[CELLOBIOSE —— 1 MICROBE————---» 2 MICROBES

naLrose |= ——
POLYRERS ——=
/xYLOB10sE —~

GLUCURONIDES ADP ATP
xyLDsE ——— Nas

SUGARS HEXOSES VER, CHy, COs
ORGANIC ACTOS

Because microbial cells are more reduced than the substrate fermented, the
quantity of microbial cells leaving the rumen per unit of carbohydrate consumed
has a large effect on the overall methane production (Table 4.1; Figure 4.2).

4.6 A model of fermentation in the rumen

For the purposes of the present discussion, a model for a 200 kg steer will be used
to illustrate the quantitative aveilability of nutrients from rumen fermentation.
The steer consumes 4 kg which represents 25M anhydroglucose of organic matter
which is completely fermented in the rumen.

It is assumed:

e that the fermentation of 1 mole of carbohydrate from forage gives rise to
either 2 mole acetate, 2 mole of propionate or 1 mole of butyrate, according
to the following stoichiometry:

Hexose —+ Pyruvate + 2ATP + H>

2 Pyruvate + 2H,0 —> 2HAc + 2CO, + 2H, + 2ATP
2 Pyruvate + 8[H] —+ 2HPro + 2H,0 + 2ATP

2 Pyruvate + 4{H] —> HBu+ 2H, + 2CO, + 2ATP
CO, + BR, — + CH, + 2H,0 + 2ATP

48



Application of strategic

supplementation: some Overview of providing protein
important considerations meals in developing countries

Some legumes that contain tannin may be protected by the tannin (3-6%
being optimum) and this should be given prominence for research.

8.6 Overview of providing protein
meals in developing countries

The options for making protein meals available are:

e more local use of protein resources rich in bypass protein

e reduced emphasis on export of protein meals as a foreign currency source
and perhaps subsidise imports of protein meals in developing countries

@ development of treatment methods to ensure a high proportion of a protein
in a meal reaches the small intestine of the ruminants to which it is fed

e development of crops that can be locally grown and processed to give a high
degree of protection to the protein

e development of forage/tree legumes whose leaves can be harvested and pro-
cessed to produce a meal rich in bypass protein

8.7 The need for feed mills

The need is for feed mills to manufacture both the MUB (or other forms of
supplements) and treat or at least process protein meals. Undoubtedly, except
for cottonseed, linseed and possibly guar meal, most protein sources will need
to be processed. In addition, the protein meals will need to be fortified with
minerals/vitamins where they are to be used to feed lactating animals. Therefore,
the development of small mills for this purpose would be an important priority.

97



Executive summary Tables and Figures

Figure 1: This appears later as Figure 5.3
(A) The effects of improving the efficiency of rumen fermentative activity on
methane production per kg of digestible energy consumed.

(B) The production of methane per kg gain in supplemented cattle (feed conversion
efficiency (FCR) 9:1) or unsupplemented cattle (FCR=40:1) fed straw based diets
(after Saadullah, 1984)

(A) 205

=>

iss)

~~

nN

o

oO
J

NO SUPPLEMENTS:

1o,)
r

800~

ANI

400~

0 ie) Z

Figure 2: This appears later as Figure 5.4

Effects of supplementation and straw treatment on the kg methane produced for
each kg gain in cattle fed straw that was untreated or treated with ammonia to
improve its digestibility. The results are from experiments published by Perdok et
al., 1988

jethone Production

eos Lwt. gain)

on
1

% digestible ene
fermented to methene
=
oO
n
r=

12005
Zz
oO
§-> 1000+ &
Ss
aN z
a om YG é
oF z
ec
ES
© 600+ 3
a Y E ==
rad — is
oP 400+ Zi * F £2
Ss Yi SG 26
so GY i— Ea vo
@2 2004 Yi 32 25
=
Bs g°
©. jn et
22



Strategic supplementation
Executive summary ‘ and the target groups

2.7 Strategic supplementation
and the target groups

A total supplementation package consisting of a multinutrient block plus a by-
pass protein feed needs to be applied to ruminants fed relatively poor quality
forages/pastures.

The target groups of large ruminants for this strategy include the following:

1. Cattle/buffalo in developing countries:

e fed crop residues or cut/carry grass and agro-industrial byproducts

© grazing in areas with monsoonal climates in the tropics, particularly
in the dry season

© grazing tropical grasslands on infertile soils (e.g. Los Llanos, Colombia;
Brazil and the pampas, Argentina)
2. Cattle in the developed or industrialised countries:
e fed agro-industrial byproducts (e.g. molasses, sugar beet pulp or
pineapple waste) :

¢ fed relatively low-protein grain based diets in feed lots (e.g. sorghum
and whole maize cobs)

© grazing relatively poor pastures in semi arid grazing areas (e.g. parts
of the Southern United States and Northern Australia)

2.8 Requirements for
success of strategic supplementation

The development of these feeding systems in India has clearly shown the ap-
plicability of this strategy. It cannot be assumed that methods used to obtain
acceptance by farmers will be viable in other developing countries.

18



References

Chalupa, W. (1988). Manipulation of rumen fermentation. In: Recent Devel-
opments in Ruminant Nutrition 2, pp. 1-18 [W. Harsign and D.J.A. Cole,
editors]. London: Butterworths.

Coleman, G.S. (1975). Interrelationship between rumen ciliate protozoa and
bacteria. In: Digestion and Metabolism in the Ruminant, pp. 149-164 (LW.
McDonald and A.C.I Warner, editors]. Armidale, Australia: University of
New England.

Crutzen, P.J., Aselmann, I. & Seiler, W. (1986). Methane production by
domestic animals, wild ruminants, other herbivorous fauna and humans.
Tellus 38B: 271-284.

Hennessy, D.W. (1986). Supplementation to reduce lactational anoestrus in
first-calf heifers grazing native pastures in the subtropics. Proceedings of
the Australian Society of Animal Production 16: 227-230.

Hennessy, D.W., Williamson, P.J., Nolan, J.V., Kempton, T.J. & Leng, R.A.
(1983). The roles of energy- or protein-rich supplements in the sub-tropics
for young cattle consuming basal diets that are low in digestible energy and
protein. Journal of Agricultural Science, Cambridge 100: 657-666.

Hennessy, D.W., Kempton, T.J. & Williamson, P.J. (1989). Copra-meal
as a supplement to cattle offerred a low quality native pasture hay. Aus-
tralian Journal of Agricultural Science 2: 77-84.

Hungate, R.E. (1966). The Rumen and its Microbes. New York: Academic
Press.

ILCA (International Livestock Centre for Africa). (1983). ILCA Annual
Report. Addis Ababa: ILCA.

Isaacson, H.R., Hinds, F.C., Bryant, M.P. & Owens, F.N. (1975). Effi-
ciency of energy utilization by mixed rumen bacteria in continous culture.
Journal of Dairy Science 58: 1645-1659.

Jackson, M.G. (1981). A new livestock development strategy for India. World
Animal Review 37: 2-8.



Overview of animal production

Introduction in developing countries

Table 3.1: FAO statistics for livestock populations in Asia/Pacific region as of
1986. (Values in the table are in thousands.)

Cattle Buffaloes Pigs Sheep Goats
World 1,271,810 138,352 822,443 1,145,690 492,192
Asia/Pacific 395,472 133,495 407,221 457,690 244,913
India 200,000 75,010 8,700 54,560 102,870 f
Pakistan 16,479 13,384 _ 25,826 30. 785
Bangladesh 23,200 1,860 _ 1,110 10,772
China 66,925 20,038 338,074 94,210 61,901

fertiliser, which, with certain exceptions (temperate pasture lands), leads to poor
nutritional value of the pasture (Walker, 1987). The animals under these grazing
systems have similar nutritional problems to those of cattle fed crop residues.

3.2 Overview of animal production
in developing countries

The majority of large ruminants in the world are in developing countries and are
owned by smallholders (in groups of 1-5 animals). They often have multipur-
pose roles; they provide draft power, milk, meat, hides, and manure for fuel and
fertiliser. The reason for cattle ownership varies from country to country.

In India, with its large vegetarian population, the emphasis is traditionally
on milk production, draft power and production of dung for fuel, whereas in many
African countries large ruminants are kept for meat and draft power with milk
and dung as byproducts.

30



Stimulating rumen

Modifying methane production fermentative efficiency .

Basically there are three approaches to increasing animal productivity from
Poor quality forages these include:

© supplementation to improve the animal's feed conversion efficiency
© chemical treatment to increase digestibility of the basal forage

@ treatment plus supplementation.

The theoretical effects of stimulating production of ruminants and methane
production per unit of product are discussed in quantitative terms.

5.1 Stimulating rumen
fermentative efficiency

5.1.1 Chemical manipulation

Manipulation of the rumen by the use of specific chemical additives to increase
propionate production or microbial cell yield relative to acetate production, has
generally resulted in relatively small responses in animal production but large
decreases in methanogenesis (from 10-80%) (see Chalupa, 1980). Often there has
been an increase in efficiency of feed utilisation rather than an actual increase
in productivity. Depending on level of application, the chemical additives have
tended to reduce rumen fermentation rates, at times allowing a greater proportion
of the diet to pass to the lower digestive tract. Digested feed as against feed
fermented does not give rise to methane. This is beneficial when the diet contains
starch, but may be detrimental if the diet consists of refractory plant cell wall
materials. In the latter case, increased methane production in the lower digestive
tract will result in a higher proportion of the digested feed being converted to

methane, because the microbial cells produced in the lower intestines are largely
lost in feces.




Part 6

Strategic supplementation
of cattle and buffaloes in India

Part 6 outline: Strategies that can be used in practice to stimulate feed con-
version efficiency of large ruminants in India are discussed. These include
supplementing cattle (buffaloes) on crop residues with molasses urea multinu-
trient blocks (to stimulate rumen microbial activity) and with bypass protein to
stimulate the efficiency of feed utilisation per unit of product (milk) formation.

The background research and demonstration trials undertaken in India are
reviewed.

The effects of such feeding strategies on growth, age at first calving and lacta-
tional yield all indicate that productivity can be stimulated many fold.

The effects of introducing these feeding systems in India to cattle and buffalo
in villages covered by a major milk shed is reported. In this milk shed, milk
Production increased by about 50,000,000 kg (or 30%) in 1989 when these
strategies were introduced, as compared to the previous two years.



Executive summary Tables and Figures

Figure 4: this appears later as Figure 5.2

Schematic relationship between diet quality (metabolisable energy MJ/kg dry mat-
ter) and food conversion efficiency (g liveweight gain/MJ ME) (- - -) (from Web-
ster, 1989). The relationships found in practice with cattle fed on straw or am-
moniated straw or poor quality hay with increasing level of supplementation of
protein meals that pypass rumen fermentation. Australia (O, 0, ¢) (Perdok et
al., 1988); (0, A) (Hennessy et al. (1983); Hennessy et al., 1989), Thailand (A)
(Wanapat et al., 1986) and Bangladesh (QO) (Saadullah, 1984) This illustrates
the marked differences that result when supplements high in protein are given to
cattle on diets of low ME/kg DM

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Consequences of
widespread application of feeding
and breeding in India Overall conclusions

Tf the low producing animals could be somehow removed from the national
herd, the decreased competition and therefore increased availability of better
quality forage per milking animal would have a multiplier effect to further increase
milk production per animal and further reduce the number of animals needed.

7.6 Overall conclusions

Improved nutrition of large ruminants fed on crop residues, agro-industrial byprod-
ucts or tropical pastures can considerably influence the rate of individual ani-
mal production through its direct effects on the efficiency of liveweight gain and
through improved reproduction rate.

Improved animal production per animal reduces methane generation by its
effects in the rumen and through decreases in age to slaughter for meat animals.
The likely improvements in milk yield, combined with a decreased intercalving
interval and age at first calving, will have a multiplier effect and eventually allow
a decrease in numbers of dairy animals to occur. The calculated production of
methane relative to milk yield over a lifetime may be reduced in cattle fed poor
quality forages fron 250 g/litre milk to 50-70 g/litre milk.

Establishing large numbers of crossbred cows in developing countries for
milk production and using the male offspring as bullocks could reduce the need
for large national herds of cows which provide the young stock for draft purposes.
Such action would remove the need to maintain at least 40 million milch animals
in India alone.

Better feeding of male offspring in early life will increase adult size and
with better agricultural implements could replace two small draft animals with
one well grown animal.

Better feeding of draft bullocks, using molasses/urea blocks, will reduce
methane generation from this source by about 50%.

The net effect of improved management on methane production will be a
reduction of approximately 60% in methane produced per unit of milk or meat
production. Provided individual production is increased and cattle numbers are
reduced, the methane production from large ruminants in India may be reduced
to 25% of its present estimated level.

90



8 Application of strategic supplementation:
some important considerations

8.1
8.2
8.3
8.4
8.5

8.6
8.7
8.8
8.9

Introduction

Application of MUB

Availability of bypass proteins

Protection of oil seed meal residues

Sources of bypass protein
in countries with no oilseed industries

Overview of providing protein meals in developing countries
The need for feed mills
Education

Cash flow of small farmers and purchase of supplements

8.10 Government subsidies

9 References



Strategic supplementation
of cattle and buffaloes in India Introduction

6.1 Introduction

Feeding systems based on an inexpensive (and available) basal carbohydrate
resource such as a crop residue or pasture supplemented with a multinutri-
ent/minerals block and a protein meal rich in bypass protein, have major impli-
cations for increasing productivity of cattle/buffaloes in many tropical countries.

There is, however, a natural reluctance particularly of smallholder farmers
to use feeds containing urea, because its mis-application can easily lead to death
of a cow from ammonia toxicity.

The use of bypass protein meals to increase feed conversion efficiencies,
although scientifically established, is only beginning to be applied. The reason
for this is associated with the uncertainty of the content of bypass protein in the
protein meals that are locally available.

The NDDB of India recently commenced the production of a 30% bypass
protein meal in one major feed mill (Amul) and this is rapidly expanding to all
28 mills controlled by the NDDB. Estimated production at the time of writing is
about 400 metric tons per day, but trials from a number of mills have raised the
daily production rate of bypass protein pellets to in excess of 500MT/day.

6.2 Molasses/multi-nutrient blocks

The National Dairy Development Board (NDDB) of India has successfully intro-
duced multi-nutrient blocks based on molasses/urea for lactating buffaloes and
cows under village conditions to meet the need of these animals for fermentable-
nitrogen (urea), minerals, and growth factors for rumen microbes such as amino
acids and possibly peptides normally deficient in diets based on crop residues.
Multi-nutrient block-licks (MUB), based on molasses/urea, have increased the
intake and growth of cattle on straw based diets (Table 6.1). Some idea of
the block, its commercialisation and its application can be seen in Figures 6.1
and 6.2. Under village conditions providing cattle and buffaloes with blocks has
led to substantial increases in milk yield and milk fat percentage (Table 6.2). The
average increase in milk yield of buffaloes and cows when MUB is introduced into



Strategic supplementation
of cattle and buffaloes in India The use of bypass proteins in India

Figure 6.4: Average 905 d lactation yield of different breeds of cattle in the
first five lactations. The animals were all fed a tropical forage supplement with
MUB/bypass protein (Source: Annual Report, Sabramati Gaushala, 1987-88
NDDB Anand

e Average lactation yield (00 kg)

404 "-Kankre] ~~ Jersey ~~ Crossbred
384
36 4
34>
324
304
284
264

Lactation Number



Contents

1 Preface

2 Executive summary
2.1 Introduction
2.2 Methane production by ruminants
2.3 Methane production by cattle fed poor quality forage
2.4 Effects of supplementation on breeding herds
2.5 The role of improved animal genotype
2.6 Improved animal production and methane production
2.7 Strategic supplementation and the target groups
2.8 Requirements for success of strategic supplementation
2.9 The Indian experience
2.10 Socioeconomic considerations (a cautionary note)

2.11 Tables and Figures



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HIGHSMITH #45115

US. EPA Headquarters Library
Mail code 3201
1200 Pennsylvania Avenue NW
Washington DC 20460



Strategic supplementation
of cattle and buffaloes in India The use of bypass proteins in India

Table 6.2: Average milk and milk fat sold per buffalo before and after the intro-
duction of molasses/urea blocks into villages in the Kaira Milk Producing Union
Ltd., Anand, India

Average milk sold
(kg/d/animal) Fat (g/d)

Before With Before With
Village (no block) block (no block) block

Alwa 4.8 5.9 330 450
Punadhara 4.0 4.8 270 340
Fulgenamuwada 2.4 3.5 160 280
Hirapura 4,2 5.2 350 480
Banroli 3.6 4.2 270 380
Dehgam 4.3 4.7 310 350

Source: Kaira District Co-operative Producers’ Union Ltd., Anand, India.
(Kunju, 1986)

Milk yield of native and crossbred cattle fed ammoniated (urea-ensiled)
tice straw supplemented with fish meal (range was 0-400 g/d) (from Saadullah,
1984) are shown in Figure 6.3. The results of this experiment clearly indicate the
improvements possible in milk yield of exotic animals of high genetic potential.
More recent applied results from milk production systems based on low quality
forages and protein meals are shown in Table 6.4.



References

Leng, R.A. (1989a). Recent advances in applied aspects of ruminant physiology
and nutrition. In: Proceedings of a satellite symposium on Ruminant Phys-
tology and Nutrition in Asia—VII International Symposium on Ruminant
Production, Sendai, Japan. (in press).

Leng, R.A. (19895). Some factors influencing the efficiency of feed utilisation
by ruminants with special reference to the tropics. In: Recent Advances
in Animal Nutrition in Australia—1989, pp. 75-89 [D.J. Farrell, editor].
Armidale, Australia: University of New England.

Leng, R.A. & Brett, D.J. (1966). Simultaneous measurements of the rates
of production of acetic, propionic and butyric acids in the rumen of sheep
on different diets and the correlation between production rates and con-
centration of these acids in the rumen. British Journal of Nutrition 20:
541.

Leng, R.A. & Kunju, P.J.G. (1988). A new approach on protein nutrition
for ruminants. Report published by the NDDB (Anand, India).

Leng, R.A., Nolan, J.V. & Kempton, T.J. (1977). Non-protein nitrogen and
bypass proteins in ruminant diets. A.M.R.C. Review No. 33. pp. 1-21

Leng, R.A., Perdok, H.B. & Kunju, P.J.G. (1987). Supplementing fibrous
feeds to increase ruminant production. In: Proceedings of the 4th AAAP
Animal Science Congress, [T.F. Reardon, J.L. Adam, A.G. Campbell and
R.M.W. Sumner, editors]. Feb. 1-6, Hamilton, New Zealand. pp. 70-73.

Lewis, M., Klopfenstein, Britton. R. & Winowiski, T. (1988). Non- en-
zymatic browning with sulphite liquor reduces rumen degradation of soy-
abean meal. Beef Cattle Report (Nebraska) 1988: 48-51.

McNamara, R.S. (1985). The Challenges for Sub-Saharan Africa. Sir John
Crawford Memorial Lecture, Washington, DC.

Nolan, J.V., Leng, R.A. & Demeyer, D.I. [editors] (1989). The Roles of
Protozoa and Fungi in Ruminant Digestion. Armidale, Australia: Penam-
bul Books.

Perdok, H.B., Leng, R.A., Bird, S.H., Habib, G. & Van Houtert, M. (1988).
Improving livestock production from straw-based diets. In: Increasing

103



Na

Consequences of
widespread application of feeding
and breeding in India Effects on reproduction rate

The strategy for meeting the increased milk production estimated to be 23
million metric tons 1985-86 to 80 million metric tons in 2000 A.D. requires much
planning.

There is basically only one option and that is to employ the new feeding
systems and to replace a proportion of the present herd with crossbred cows
and selected buffaloes (with widespread use of AI) and eventually reduce overall
animal numbers.

7.2 Effects on reproduction rate

Using the feeding strategies discussed above, it has been unequivocally demon-
strated that age at puberty can be reduced from 4 to 1.5 years and that intercalv-
ing interval can approach 12-15 months as against 2 years in most nondescript
cattle/buffaloes in India, Even mature cows and buffaloes subjected to long term
undernutrition begin their reproductive cycle when given only MUB with their
allowance of straw. It is obvious that even with low producing animals, increasing
reproduction rate to one calf per year can almost double milk production within
the country,

7.38 Milk production and draft power

To produce the 80,000,000,000 kg of milk needed/year in India would need only
a population of 27 million crossbred cattle and buffaloes with an annual milk
production of 3000 litres. In addition to this India requires about 10 million
bullocks annually to meet replacements required to maintain the 75 million herd
of draft animals. These could be available from the 27 million dairy animals
as this could be expected to produce 13 million male offspring per year. This
supposes a cross-bred is produced with suitable draft characteristics.

88



Stimulating rumen
Modifying methane production : fermentative efficiency

Of note is that the mechanisms by which ionophores and halogens reduce
methane generation are actually quite different. lonophores reduce methane emis-
sions in part by increasing feed efficiency. Additionally, they inhibit bacteria that
produce hydrogen and are subsequently used by methanogenic bacteria. As a
contrast, the halogens are believed to inhibit the methanogens directly. This in-
hibition may also reduce rumen digestion efficiency, which is counterproductive
from a production standpoint.

In the developed countries, industry may need to be persuaded to develop
highly effective chemicals agains methanogens and farmers may have to be per-
suaded to use these even where there is no economic advantage.

5.1.3 Improving efficiency of microbial growth

Most forages fed to ruminants in the tropics can be deficient in nitrogen, sulfur,
trace minerals and often phosphorus and sodium. Ammonia, sulfur and phospho-
rus are the most likely deficient nutrients for rumen microbes.

The following have all been found to increase microbial protein availability
to ruminants fed forage based diets (and therefore increase P/E ratios):

supplementation with urea/sulfur

@ supplementation with slowly degraded protein which provides amino acids/
peptides for rumen microbes

e elimination of rumen protozoa (see Bird & Leng, 1984)
© increasing rumen digesta turnover, which decreases residence of digestion

and bacteria have a lower maintenance requirement,

The first three methods of improving the efficiency of microbial growth have
been demonstrated in the animal, whereas the fourth is rarely feasible in practice.

56



Digestive physiology of
ruminants: implications for
improving animal production

from poor quality forages Applied significance of P/E ratio

of disulphide bonds tends to bypass rumen fermentation but is digested in the
intestines and in this way it alters the ratio of protein to energy (P/E) in the
nutrients absorbed. The better the balance of nutrients for microbial growth the
higher the ratio of P/E of the nutrients absorbed.

4.8 Applied significance of P/E ratio

The amino acid supply to an animal effects a large number of biological functions
within the animal. Obviously where end-products containing protein are the
objective of the feeding system the amount of amino acids absorbed relative to
VFA will be highly correlated with the productive level achieved. For example,
wool growth, milk production and growth in young animals all increase with the
increase in the P/E ratios in the nutrients available to the animal. The higher
the P/E ratio in the nutrients absorbed, the more efficient the animal becomes
in utilising the available nutrients for milk production, liveweight gain and other
production functions.

4.9 Significance of protein in the diet

Considerable research has demonstrated that, in ruminants fed poor quality for-
ages, supplementation with a source of rumen ammonia (or molasses /urea multi-
nutrient blocks) stimulates rumen function, which stimulates food intake. On all
diets that are low in protein, supplementation with bypass protein stimulates the -
efficiency of feed utilisation and/or feed intake. This principle appears to hold for
a wide variety of diets from fibrous cereal crop residues through to diets. based on
starches (barley) and sugars (molasses) (Preston & Leng, 1987) and is discussed
extensively in Part 3.

52



: Methane production
Executive summary by cattle fed poor quality forage

Over the last 20 years, increases in animal products have been achieved
in developing countries by increasing animal numbers rather than increasing the
level of production per animal. These countries have over half the total world
ruminants, and they are, in general, owned in small groups (i.e., 1-5 animals) by
small farmers and are fed on forages which generally promote slow growth, poor
reproductive performance and low milk production.

The pressure on land in most developing countries for food-crop production,
suggest that it is not possible to alter the basal diets of these animals, which are
generally fed on poor pasture and/or crop residues that are low in protein and
digestibility. The feed resource is usually of poor quality for the majority of
any feed year. Methane production by these animals may be as high as 15% of
the digestible energy of feed since the diets are deficient in critical nutrients (in
particular ammonia) for efficient microbial growth in the rumen.

2.3 Methane production
by cattle fed poor quality forage

Data developed from extensive work in India and other countries indicate that
strategic supplementation of the diet to promote efficient fermentative digestion
of forages will decrease methane generation per unit of digested feed by some
30-50% (15% of digestible energy (DE) to 7% of DE).

These data also show that in addition to ensuring an efficient fermentative
digestion in these ruminants, judicious supplementation with protein, in a form
that is directly available to the animal, reduces the time for an animal to reach
slaughter weight or puberty by up to three years (from a “normal” 5-6 years
down to 2-3 years) and reduces the amount of forage required to grow an animal
to slaughter weight or to a breeding size by 4 to 5-fold. Over a 12 month period
(1989) close to 50,000,000 extra litres of milk have been produced in Kiara, as
against 1988 and 1987, when traditional supplementation was used. Methane
production per unit of meat produced is reduced to about 0.2 of that produced
in the unsupplemented animal. For milk production, the amount of methane
produced can be lowered from about 250 g methane/litre to 40-80 g methane/litre
of milk.

14

ee — — — — — — -


Part 4

Digestive physiology of
ruminants: implications for
improving animal production

from poor quality forages

Part 4 outline: The information given in this chapter is fundamental to under-
standing the strategies for limiting methane production from ruminants. As-
pects covered include anatomy of the ruminant, the microbiology of the rumen,
the requirements of rumen microorganisms for nutrients and the stoichiometry
of rumen fermentative digestion of feed and the balances of nutrients available
to the animal. Applied significance of the balances of protein to energy in the
products of digestion that are absorbed is discussed.

4.1 Introduction

An understanding of the digestive physiology and metabolism of ruminants is the
foundation for developing appropriate strategies that best utilise available feed
resources and which at the same time minimise enteric methane production.



Digestive physiology of

suminants: implications for

improving animal production Consequences of
from poor quality forages the ruminant mode of digestion

4.4 Consequences of
the ruminant mode of digestion

One of the costs of the ruminant mode of digestion is that fermentation of the
readily digestible feeds results in up to 20% of the digestible energy in the feed
consumed being lost as heat and methane. A second major disadvantage is that
proteins that are fermented in the rumen are lost as sources of amino acids.
Skillful balancing of the nutrients for the rumen and the animal can have very
large effects on animal production through effects on the efficiency of all important
functions.

In general, where a ruminant is fed a forage based diet typical of that
available in tropical developing countries, small amounts of extra nutrients are
needed to increase the efficiency of digestion and also the efficiency of anabolism
of the absorbed nutrients in growth, pregnancy, lactation or work.

4.5 Quantitative aspects
of fermentative digestion
in the rumen

The end products of rumen fermentation are governed by the feed, the rate of
consumption of feed, the balance of nutrients in the feed for microbial growth
and the balance of microorganisms that develop (bacteria, protozoa and fungi)
which largely depend on the chemical composition of the diet.

In general, a proportion of the digestible feed dry matter is converted to
volatile fatty acids (VFA), methane and carbon dioxide and the balance is assim-
ilated into microbial cells. The pathways of these reactions are well known (see
Baldwin, 1970; Leng, 1970) and a schematic outline is shown in Figure 4.1.

Microbial cells, that are synthesised using the ATP generated in the forma-
tion of VFA, are lost from the microbial biomass pool either by passage out of
the rumen to be digested in the intestine or by death and breakdown within the
rumen (with formation of VFA, CO, and methane).



Strategic supplementation Lo.
of cattle and buffaloes in India The use of bypass proteins in India

Figure 6.2: Colour plates to illustrate the method of presentation of MUB to cattle
and buffaloes.

A: Cattle in Indian village. 1: Small farmer condition, bowl being used as a

receptacle for the block. 2. Large farmer condition, plastic containers attached to
the wall of the shed.

B: Buffaloes under institutional management, blocks without holders simply placed
on a concrete slab.

76



Some practical results from commercial milk producing systems
where feed resources are based on forages

Supplementing with soyabean meal or soyabean meal treated with
sulfite liquor



Digestive physiology of

ruminants: implications for

improving animal production

from poor quality forages Protein utilisation by ruminants

In the example, one-third of the carbohydrate provides the precursor for
microbial cells, 1300 g dry microbial cells are produced at a Yarp of about 14.5.
(Yarp is a measure of the efficiency of utilisation of ATP generated in fermenta-
tion of carbohydrates to VFA; it is defined as the g dry cells produced per mole
ATP available. The relationship between cell synthesis and organic production.
is shown in Figure 4.1.)

The upper level of efficiency (or the theoretical highest level of cell produc-
tion) has a Yarp of 26. On the other hand the lowest efficiency of a microbial
growth in the rumen that is deficient in, say, ammonia, is probably below a Yarp
of 4.

Based on this model, but assuming a varying efficiency, the microbial cells
produced relative to VFA and methane production change as shown in Table 4.1.
The main point to emphasise is that, depending on the efficiency of utilization
of ATP for microbial cell synthesis, the amount of carbohydrate converted to
microbial cells can be highly variable and it is this that controls the amount of
methane and VFA produced (see Figure 4.2).

4.7 Protein utilisation by ruminants

Protein that is fermented in the rumen is largely wasted as a source of amino
acids to the animal because:

e dietary protein is degraded and essential amino acids are deaminated to
form ammonia and VFA

fermentation of 1 g of protein generates only half the ATP that would be
produced from 1 g of carbohydrate.

This means that only 30 to 60 g of microbial protein becomes available to
the animal for digestion for every kilogram of dietary protein that is fermented
in the rumen. The fermentation of protein is associated with only smal] amounts
of methane produced; on the other hand methane generation from protein if this
bypasses the rumen is zero.Protein that is insoluble or has a high component



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Modifying methane production

Figure 5.6: Calculated amounts of methane produced per unit of milk production in
unsupplemented (fed traditionally) or supplemented (new feeding systems) cows in India
with moderate levels of production. The methane generated (9) per kg milk is also shown
for high yielding cows in developed countries (fed traditionally) or high yielding cows in
India fed tropical forage with molasses urea block (MUB) + 350 g/d bypass protein per

liter of milk production.

The values represent the methane generated from feed consumed during the lifetime of
the cow in relation to the lifetime’s milk yield. The assumptions associated with this

figure are tabulated.

Case Study

1 2 3 4
Mature weight (kg) 400 400 600 600
Time of first calf (years) 5 3 2 2
Intercalving interval (years) 2° «15 1 1
FCR® (kg/kg LWt gain) 30:1 15:1 8:1 8:1
Forage consumption (% LWt) 2.5 3 4 4
Digestibility of feed (%) 50 5065.
Methane (% Dig. Energy) bB Ml Nn
Life span (years) 1300«13 5 8
Number of lactations 4 6 3 6
Lactation yield (tons/year) 1 25 6 6

*FCR = Feed conversion ratio (from weaning to first calf)

Case studies:

1, Traditional feeding with native
cattle/buffalo in India.

2. New feeding system using MUB/
bypass protein with native buffalo in
India.

3. Friesian-Holstein fed high qual-
ity forage/concentrate in developed
countries,

4. Friesian-Holstein fed tropical for-
age/MUB/bypass protein in India.

68

300

¥ osp4 __ 242

= 250

x}

£ 2007

3

3 1504

8 1004 7%

be «#0

=
‘Traditional + supplements: Friesian Friesian
feeding U.K. India

Improved animal production rate
and methane production


Executive summary Tables and Figures

Figure 3: This appears later as Figure 5.6

Calculated amounts of methane produced per unit of milk production in unsupplemented
(fed traditionally) or supplemented (new feeding systems) cows in India with moderate
levels of production. The methane generated (g) per kg milk is also shown for high
yielding cows in developed countries (fed traditionally) or high yielding cows in India
fed tropical forage with molasses urea block (MUB) + 350 9/d bypass protein per liter
of milk production.

The values represent the methane generated from feed consumed during the lifetime of
the cow in relation to the lifetime’s milk yield. The assumptions associated with this
figure are tabulated.

Case Study Case studies:

1 3 1, Traditional feeding with native

Mature weight (ke) 400 cattle/buffalo in India.

‘Time of first calf (years) 5 2 2, New feeding system using MUB/
Intercalving interval (years) 2 7 1 bypass protein with native buffalo in
FOR? (kg/kg LW¢ gain) 30:1 8:1 8:1 | India.

Forage sai ot nt LWt) 25 4 3. Friesian-Holstein fed high qual-
Digestibility of fe: 50 + +
Methane (% Dig, Energy) 15 ul ity forage/concentrate in developed

Life span (years) 13 5 countries.
Number of lactations 3 4. Friesian-Holstein fed tropical for-

Lactation yield (tons/year) 6 age/MUB/bypass protein in India.
*FCR = Feed conversion ratio (from weaning to first calf)

3004

3
8

3
g

36

Methane produced/g/litre of milk
8B

8

Traditional + supplements Friesian
feeding UK.

23



Improved animal production rate

Modifying methane production and methane production

Figure 5.4: Effects of supplementation and straw treatment on the kg methane
produced for each kg gain in cattle fed straw that was untreated or treated with
ammonia to improve its digestibility. The results are from experiments published
by Perdok et al., 1988

12005

=
S—> 1000 GH
ot =
oe 8004 £
Uw +
o oO
ec
25 6004 Yy 3
eo 3
= — 4
ie: = Be
oD 400-+ 2 ros
co —_ SE
oF ee Hy oo
so — i yo
@:2 200+ — £e
= ae SO z

oe 3°
° on e+

The effects of straw treatment to improve digestibility and supplementa-
tion on methane generation are shown in Figure 5.4. The data in this case were
generated in a temperate climate (Perdok et al. 1988). The relationship be-
tween the metabolisable energy content and the efficiency of growth per unit of
methane production is shown in Figure 5.5 and is calculated from the data given
in Figure 5.2.

Because there are a number of assumptions made in calculating these values,
the total amounts of methane produced will have a large standard deviation
depending on a number of factors. The values for methane production are meant
to convey the potential for reduction of methane generation by supplementation
to improve fermentative digestion and by supplementation and straw treatment
to improve efficiency of feed conversion.

66



Stimulating rumen
Modifying methane production fermentative efficiency

5.1.6 Controlling rumen protozoa

Although there has been considerable controversy on the role of rumen protozoa,
it seems to be now accepted that protozoa account for the turnover of a large
proportion of the bacterial pool in the rumen. They also increase the degradation
of dietary protein in the rumen (see reviews in Nolan, Leng & Demeyer, 1989).

The removal of protozoa from the rumen and the maintenance of the un-
faunated state may increase microbial cell outflow from the rumen by 25-50%.
In turn this will reduce methanogenesis per unit of carbohydrate fermented by
approximately 25% (see Table 4.1). The improved protein to energy ratio in the
nutrients arising from rumen fermentation increases the efficiency of feed utilisa-
tion and decreases the feed required per unit of live weight gain, further reducing
methane production per unit of meat or milk production.

The control of rumen protozoa is not feasible at present, but pharmaceuti-
cal companies are actively screening chemicals for this purpose. In the author’s
laboratory a natural forage has been found, which, in small quantities, will elim-
inate protozoa from the rumen and trials are already underway to test practical
strategies for control of ramen protozoa.

5.1.7 Overall effects of improving microbial growth effi-
ciency

Undoubtedly, on poor quality forages, the effect of providing critical nutrients for
microbes in the rumen is to increase microbial growth efficiency and digestibil-
ity. In tropical areas, or where animals are under heat stress, feed intake is
also increased (Leng, 1989). The overall effect is to increase the efficiency of
fermentative digestion which decreases methanogenesis per unit of carbohydrate
degraded, but it may increase methanogenesis per animal. On the other hand the
animal grows with less feed/unit of growth, reaches maturity at an earlier time
and feed requirement per unit of liveweight gain is markedly reduced.

The conclusion is that whilst methanogenesis is reduced per unit of feed
digested, the methane produced by the animal is increased. On the other hand
this is the first step in improving the efficiency of animal production (see later) and
reducing overall feed requirements per unit of liveweight gain or milk production.

59



Executive’ summary

The role of improved animal genotype

The supplementary feeding strategies, but not the treatment of straw are
being widely advocated for cows and buffaloes in villages throughout India by
the National Dairy Development Board. Their policy is to turn over all their feed
mills to producing protein meals which are prepared so that the protein escapes
fermentation and is used directly by the animal. They have in place, or have
planned, some 50 factories to produce molasses/urea multinutrient blocks. The
use of these two supplements can achieve the increases in production sufficient to
reduce methane emmissions significantly.

It is possible that within five years, six million animals will be
being fed by these strategies in India alone. The wider scale application
in other developing countries of these feeding strategies depends on

political will, socio-economic factors and perhaps pressure from Aid
Agencies.

2.5 The role of improved animal genotype

More scientific feeding of ruminants allows the use of improved genotypes for
the particularly productive system. In India, for example, introduced cattle for
crossbreeding purposes (such as Friesian-Holstein or Jersey with high genetic
merit) have milk yields in their first lactation of 4000-6000 litres/305 days without
resorting to grain based concentrates.

The projected requirements for milk and draft power in India could be met
by 27 x 10° cows/buffaloes producing 3000 litres milk/year, breeding every 12
months. The male calves would provide 10 x 10° replacement bullocks needed
annually for animal draft power. The net effect could be a reduction in cat-
tle/buffalo numbers from over 300 x 10° to about 120 x 10° (which includes 75 x
10° draft animals).

16



Introduction Ruminant feed resources in Asia

Table 3.3: Average carcass weight (kg) per animal slaughtered (Jasiorowski, 1989)
(1986 statistics)

Cattle Buffalo

Europe 185 206
Asia/Pacific 120 161

Table 3.4: Average milk produced (litres/lactation) per total population or per
animal milked (Jasiorowski, 1989) (1986 statistics)

Cattle Buffalo

Europe " 860 (2335)* 586 (1043)*
Asia/Pacific 82 (865)" 284 (707)*

* milk production per animal milked.

Comparisons of productivity rates for Europe and Asia/Pacific are shown

in Tables 3.2, 3.3 and 3.4, and clearly illustrate the low productivity of large
ruminants in the Asia/Pacific region.

There are a number of ways to reduce enteric methane generation, but an
obvious method is to increase animal productivity per animal to such an extent
that the services and products provided by ruminants can be achieved by a much
reduced number of animals. _

33



Part 5

Modifying methane production

Part 5 outline: Two factors affect methane production per unit of digestible
feed; these are microbial growth efficiency and the formation of propionate in
the rumen. Higher production of either cells or propionate reduces methane
production per unit of organic matter digested in the rumen.

Microbial growth efficiency is inefficient in animals fed on forage based diets,
typical of those fed to ruminants in developing countries, and can be stimulated
by nutrient supplementation. This reduces methane generation markedly.

Factors that limit the efficiency of microbial growth in the rumen are discussed.
Ruminaats fed low digestibility forages use this more efficiently when their
protein status is improved by supplementation with a bypass protein.

Methane production per unit of production, therefore, can be ameliorated in
Practice by balancing the nutrient available from rumen fermentation with
dietary protein that avoids fermentation.

The implications for the rates of methane production per animal or per unit
of product of improving both feed conversion efficiency and growth rate are
outlined.



Executive summary The Indian experience

The essential ingredients for success with such strategies are:

identification of local resources to provide the supplements
developing raw ingredients where resources are not available locally
placing priority on the use of these resources locally

where necessary, establishing appropriate manufacturing capabilities to pro-
tect proteins from-degradation in the rumen

ensuring that the supplements are available to small farmers through an
appropriate marketing system

ensuring markets for meat/milk etc, and therefore profit motive to farmers

facilitating purchase of supplements—particularly where the returns for
their use are some time in the future—e.g. subsidies, low or zero inter-
est rates, perhaps with a tax on the commodities when sold

facilitating the use of potentially high producing genotypes by making germ
plasm available, and insurance of the animals against death

education on the benefits of such supplementary feeding strategies through
all levels of the community

ensuring that good disease/parasite control is associated with the feeding
strategies

2.9 The Indian experience

The patterns of supplement purchase, milk sold and the ratio of supplement
purchased/ milk sold in the Kiara district of India are shown in Figure 6 at the
end of this Section. The new feeding strategy was implemented in December
1988. Clearly, the advantages of the strategies are increased milk production
(approximately 30% more than in the previous 2 years) and decreased supplement
production coupled with increased efficiency of supplement use. The increased
milk production per cow reduces methane production/unit of milk. The decrease
in quantities of supplement used to feed milch animals in the villages will result in
considerable fossil fuel savings in manufacture, transport and storage processes.

19



Strategic supplementation Case study: application
of cattle and buffaloes in India of strategic supplementation

The decision to turn over the feed-mill to producing the new feeds has been
vindicated by the large increases in milk procurement by the Amul milk factory.
The milk collection by the Amul plant for the three years 1987, 1988 and 1989
are shown in Figure 6.6.

In summary, immediate benefits of the new feeding systems are:

e a 30% increase in milk procurement without any increase or change in the
feed-base

¢ a reduction in the recommended level of supplementation with compounded .
meal, increasing the effective capacity of the mill to supply critical supple-
ments for twice the number of animals

© an improved efficiency of utilisation of feed. The conversion of supplement
has been reduced from about 750 g/litre to 350 g/litre milk production

e a lowered requirement for fossil fuels in manufacture, transport and storage
of supplement

The increased milk production that has been observed is possibly an under-
statement of the longer term results. It is anticipated that there will be improved
reproduction rates in females in the coming year, possibly increasing the pro-
portion of lactating to dry cows (buffaloes) significantly in the villages. This
may result in a further 50% increase in milk production from the available feed
resources.



introduction Trends in livestock production in India

3.6.4 Integrating ruminant production
with biogas production

In the industrialised countries, feedlots are planned in order to maximise animal
productivity and minimise operational costs. This has led to the use of feed
resources with high energy and protein content (i.e., grains and oilseed meals).
These feeds are usually compounded using modern equipment that facilitates
mechanised feeding. The heavy capital investment in machinery has necessitated
the establishment of large units with high animal densities.

Waste disposal in these enterprises has become a major problem. The ac-
cumulation of wastes, the cost of their disposal and pollution of the environment
are serious consequences of the intensification of livestock enterprises in developed
countries.

By contrast, the wastes from crop and livestock production in the develop-
ing countries are valuable sources of fuel and fertilizer. Fuel (methane) can be
produced conveniently and efficiently from animal waste by anaerobic digestion.
Recycling liquified excreta through biodigestors to irrigation systems avoids the
loss of nitrogen and other plant nutrients which occurs when dried dung is burned
for cooking and reduces the need for further dependence on fossil fuels.

The major constraint to widespread acceptance of biogas technology has
been the high cost of the early digestors, which were built of concrete and steel.
Simpler designs are now available which use plastic film (see Preston, 1989).
These are easier to construct and install and are especially suitable to small
farmers who have few animals.

3.7 Trends in livestock production in India

All developing countries require increased amounts of animal products. India, for
example, produces at the present time about 163 g milk/capita and has set its
goal at 200 g daily per capita. This requires a doubling of total milk production
because of projected population increases. Jackson (1981) has pointed out that,
with the ‘feed base’ of India, increased milk production to 1981 has been through

40



Strategic supplementation
of cattle and buffaloes in India The use of bypass proteins in India

Table 6.4: Some practical results from commercial milk producing systems where
feed resources are based on forages (Leng, 1989b)

Basal feed Supplements Milk production

1. Tropical grass/maize silage Free choice 5,000-6,500 kg/305 d
or other crops plus 1-2 kg rice mollasses/urea blocks +
straw/day (Fresian-Holstein) protein pellet (30% CP)
(350 g/kg milk)
2. Rice straw/millet straw Bypass protein pellet 300 25 litres/d (at 3
(8 kg/d) (crossbred Jersey x g/kg milk months)
Kankrej)
3. ad hb. mixture of cotton- 6,200 kg/300 d (2nd
seed hulls (46%); molasses (17%); calf cows)
cottonseed meal (18%); sesame 5,700 kg/300 d (Ist
seed meal (15%); crude lecithin calf heifers)
(4%) and 10 kg freshly har-
vested kikuyu grass (2 kg DM/d)
(Friesian)
4. Cane tops (50% more than Cottonseed meal 250 2,800 (4)
daily intake) + cut carry grassas g/kg milk
available (Crossbred cows)

References: (1) NDDB, Anand Bull Mother Farm (Kurup, M. P.J. pers. comm.) (2)
Personal observations—in village system one animal only (3) C.E.Payan, V. (pers.
comm.) Aceitales §.A. Calle 12 Apartado Aero 3840 Bogota, Colombia (4) Ramjee et
al.,(1988)



Stimulating rumen

Modifying methane production fermentative efficiency

providing a molasses/urea block lick (MUB);

¢ providing a source of soluble protein as a forage (e.g., alfalfa) or grain (e.g.
lupins, peas, beans)

In most developing countries the first three are feasible but the last is rather
wasteful (as protein is fermented) and requires land for production of forage
reducing that available for cropping—a better approach that is presently emerging
is the use of tree forages for this purpose.

In most developing countries, protein is a scarce commodity and its most
useful role will be promoted if the protein'is protected from rumen fermentation.
This can be achieved by a number of manufacturing processes (see Part 6).

5.1.5 Provision of small quantities of true protein

Although there is a strong body of opinion that supports the concept of a need for
amino acids/peptides for efficient microbial growth in the rumen, little evidence
from whole animal studies is available that supports this concept. However, recent
studies have shown that diet is all important in determining whether the rumen
microbes need peptides/amino acids. Microbial growth on sugar and starch, but
not cellulose, is stimulated by protein in the incubation media, indicating that
there is a low requirement for protein fermentation in the rumen of forage fed
cattle.

In theory, the energy cost of microbial protein synthesis is largely associated
with formation of the peptide linkages and assimilation of ammonia in amino
acids is independent of ATP supply. However, strategies (to be discussed) for
feeding a bypass protein, some of which will be inevitably degraded in the rumen,
adequately cover this aspect.



Strategic supplementation
of cattle and buffaloes in India

Conclusion

The age at first calving is shown in Figure 6.5. The native breed (Kankrej)
even when fed well did not calve until 4 years of age as compared to 18 months
for the pure breed and about 2 years in the crossbred.

An elite herd of Murrah buffaloes has also been established with 305 day
milk yields of 3000-4500 litres and an on average fat percentage of 6-9% (see An-
nual Report 1987-88, Sabarmati Ashram Gaushala National Dairy Development
Board, Anand, India).

6.4 Conclusion

Research and demonstration trials have indicated the huge potential increases
in animal productivity that may result from improved nutrition at the village
level in India. When the principles were also applied to institutional-herds of
animals with high genetic potential the improvements of milk yield were much
higher than anticipated. This indicates that at the village level the maximum
milk yields obtained with supplementation were primarily constrained by genetic
potential of the animal and not by sub-optimal nutrition. Thus there is enormous
potential to improve milk production by a combination of feeding and breeding
(the assumption being made that disease is controlled).

6.5 Case study: application
of strategic supplementation

The compounding Feed Mill at Amul (Kiara district), (the largest feed mill in
India), changed from the production of concentrates to the production of a high-
protein pellet on December 1st 1988, after substantial in-village trials had clearly
demonstrated the superiority of the high protein feed.

The conversion was marked by considerable unrest at the village level, but
after a period of one to two months the farmers of the Kiara district appear to be
convinced of the value of the new feed, which is approximately 50% more expen-
sive but is recommended to be fed at half the rate of the previous concentrate.

82



Executive summary Tables and Figures

2 Supplements sold (‘000 MT/month} Mitk procured at Amut (‘OOO MT/month)
T -

-@ 1980/87 -O- 1087/88 ©-@-1988780 #1989700 -B 1980/87 -O- 1987/88 ~@ 1oBevas —* 1980/90

A

10.
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mer Apr May Jun Jul Aug Sep Oct Nov

5 Milk/suppiement (litres/kg) 100 THi - Bombay (Celsius)

-@ 198eva7 -& 1987/88 ~-G-r98eva9 =H 1989/00

Oe:

a a

oe

epg ee

5

5. 10.
Dec Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb Mer Apr May Jun Jul Aug Sep Oct Nov



44
4.5
4.6
47
48
4.9

Fermentative efficiency in the rumen

4.3.1

Meeting the requirements
for efficient microbial growth in the rumen

Consequences of the ruminant mode of digestion

Quantitative aspects of fermentative digestion in the rumen. . . .

A model of fermentation in the rumen

Protein utilisation by ruminants

Applied significance of P/E ratio

Significance of protein in the diet

Modifying methane production

5.1 Stimulating rumen fermentative efficiency

5.1.1

5.1.2
5.1.3
5.1.4
5.1.5
5.1.6
5.1.7

Chemical manipulation

Chemicals reducing methane emissions
Improving efficiency of microbial growth
Supplying deficient micronutrients for microbes
Provision of small quantities of true protein

Controlling rumen protozoa

Overall effects of improving microbial growth efficiency . .

Stimulating animal production rate

5.2.1
5.2.2
5.2.3

General
Supplementation

Treatment of forages to improve digestibility



Introduction

The overall strategy

Improved production per animal (see later) will reduce methane production
per kilogram of meat or milk produced. Improved rates of production by indi-
vidual animals could lead to a large reduction in cattle numbers once national
requirements are met. This would have a multiplier effect on the decrease in
methane production from better feeding of livestock.

No consideration is taken here of the sociological effects that this could
have on the standard of living and the populations of small farmers in developing
countries, nor how a decrease in animal numbers could be managed particularly
in Africa and India. The application of improved feeding and breeding strate-
gies must take into consideration political, economic, biological and sociological
aspects. Many of these aspects are not predictable, particularly sociological and
political aspects, and are not considered further in this presentation.

Nevertheless, the importance of these factors should not be minimized be-
cause they will have a significant impact on the ability to realize reductions in
methane emissions in many countries.

42



3 Introduction

3.1 The problem.... 2... 0.2... ce eee eee ee ee
3.2 Overview of animal production in developing countries ......
3.3 Livestock production systems: comparison between industrialised
and developing countries... 1... eee ee ee ee
3.4 Ruminant feed resources in Asia... 1.1... ee eee eee
3.5 Improving ruminant production in developing countries ......
3.5.1 Impact of climate on production of ruminants .......
3.5.2 Specialised beef cattle production ..............
3.6 Strategies for improving animal production/reducing
greenhouse gas emissions... . 2.2.2... .220 00 eee eee
3.6.1 Management to increase ruminant productivity ......
3.6.2 Integrated farming systems...............00-
3.6.3 Integration of livestock with crops/fuel production... ..
3.6.4 Integrating ruminant production with biogas production .
3.7 Trends in livestock production in India ...............
3.8 The overall strategy. 2... ee es

Digestive physiology of ruminants: implications for
improving animal production from poor quality forages

4.1 Introduction... 1... ee ee

4.2 Therumen......... eee eee ee ee ee ene



Improving ruminant production
Introduction in developing countries

Figure 3.1: Graphs illustrating the relatively stressful heat conditions throughout
the year for the tropical and temperate areas. THI 72 is believed to be the point
above which milk production is severely effected (Johnson, 1987).

Climatic conditions are indicated by Temperature—Humidity Index (THI) where:
THI (°C) = Temp. (dry bulb) + 0.36 Temp. (dew point) + 41.2°C.

° THI (Celsius)

4 Bangladesh -& Bombay -O- Denmark

60 +

507

40 + T T T T T T T T T
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov -Dec

litres/day). Average milk yields of up to 25 litres/day are, however, possible
even in the humid tropics with the appropriate feeding strategies discussed here.
(The Temperature Humidity Index (THI), above which milk production tends
to be depressed is illustrated in Figure 3.1, together with those for Bombay (In-
dia), Chittagong (Bangladesh) and Copenhagen (Denmark)). In most developing
countries the development of specialised milking herds is counter-indicated as it is
much more rational and more simple to introduce crossbreeding. When compared



so . Effects of
Executive summary supplementation on breeding herds

Other methods for improving animal nutrition, e.g. increasing the digestibil-
ity of the forage (with alkali treatments) in combination with such supplementa-
tion, can further reduce the age of slaughter and feed required per unit of meat
or milk production.

2.4 Effects of
supplementation on breeding herds

As already pointed out, in most developing countries, the animals owned by small
farmers mature at a late age (puberty at 4 years) and often breed irregularly (one
calf every 2 years). It is suggested that the strategies outlined, in the main text
have the capability of reducing the age of first calving from 5 years to 2-3 years
and the intercalving interval from 24 months to 15-12 months. This diminishes
the numbers of breeding cows required for meat production and/or providing
replacement draft animals by at least 50%. With the dairy industry it can more
than double milk production by increasing the number of cows in the National
Herd actually in milk at any one time.

Widespread application of these nutritional strategies coupled with good
health care and management can have a huge impact on animal production.
Animal production in developing countries can be improved between 2 and 4 fold
by the nutritional strategies outlined provided they can be widely applied.

The eventual overall effects on methane emission will depend on the control
of animal numbers within a country. This in turn will depend on market demand
for meat and milk and other products (including draft power). However, market
forces will surely reduce animal numbers as production per animal increases; this
has already occurred in the USA in dairying where cow numbers have decreased
linearly with increases in milk yield per animal. The increased production has
been achieved through better feeding and breeding.

Meeting the market demands for ruminant products through a higher effi-
ciency of feed utilization and animal production, together with the reduced re-
quirements for numbers of breeding cows will also reduce or remove the incentives
to create vast ranches from tropical rainforests.



Part 1

Preface

The preparation of this report was funded by the U.S. Environmental Protection
Agency (EPA). The purpose of the report is to summarize information regard-
ing the potential to reduce methane emissions from ruminants through the use
of strategic supplementation. This approach for reducing emissions was one of
several promising approaches identified and discussed at an EPA-sponsored work-
shop in February 1989 and in a workshop conducted under the auspices of the
Intergovernmental Panel on Climate Change (IPCC) in December 1989. Infor-
mation regarding these workshops can be obtained from the following:

e U.S. EPA, Reducing Methane Emissions from Livestock: Opportunities and
Issues, Office of Air and Radiation, EPA 400/1-89/002, August 1989;

e U.S. EPA, Greenhouse Gas Emissions from Agricultural Systems, Policy
Planning and Evaluation, 20P-2005, September 1990.

This report has been prepared to further discussion and analysis of oppor-
tunities to reduce emissions of greenhouse gases from various sources. The U.S.
Environmental Protection Agency does not endorse the performance, environ-
mental acceptability, or commercial viability of any of the emissions reduction
strategies discussed in this report.

10



Improving Ruminant Production and Reducing
Methane Emissions from Ruminants by
Strategic Supplementation

Professor of Nutritional Biochemistry
Director of the Institute of Biotechnology
Department of Biochemistry, Microbiology and Nutrition,
University of New England,
Armidale, N.S.W, 2351, Australia.

U.S. EPA Headquarters Library
Mail code 3201
1200 Pennsylvania Avenue NW
Washington DC 20460

HEADQUARTERS LIBRARY
ENVIRONMENTAL PROTECTION AGENCY
WASHINGTON, D.C. 20460

SEP 25 I99}





Improved animal production rate
Modifying methane production and methane production

Figure 5.3: (A) The effects of improving the efficiency of rumen fermentative
activity on methane production per kg of digestible energy consumed.

(B) The production of methane per kg gain in supplemented cattle (feed conversion
efficiency (FCR) 9:1) or unsupplemented cattle (FCR=40:1) fed straw based diets
(after Saadullah, 1984)

(A) 205 (B) 12005

=
uo
1

keg/ton Lt. gain)

e <
ao o
co vad
20 $
dE 3
29 £
2- 10- a
pv o
oo 5
Se &
oe S
“3 ces
res =

2

on
_L

o-+ 0
The assumptions are that without urea and bypass protein supplements to
cattle the efficiency of ramen fermentation of straw dictates approximately 15%
of the digestible energy is channeled into methane and about 7% when the rumen
is efficient. In the calculations of Crutzen et al. (1986) they assumed that dairy
cows (feed digestibility 75-80%) produced 5.5% of the gross energy intake as
methane for young animals (feed digestibility 65-70%) this became 6.5% whereas
for cattle on low quality forage (digestibility 45-55%) the value was 7.5%. Thus
the values used by Crutzen would indicate 7, 12 and 19% of the digestible feed
energy consumed by cattle in each of these categories was lost as methane.

In the studies reported by Saadulah (1984) from Bangladesh, cattle were fed
straw and straw supplemented with 600 g of an oilseed cake. In this case the FOR
was approximately 40:1 on a non-supplemented diet and 9:1 when supplements
were given. The methane generated per unit of digestible energy or per unit of
liveweight gain is shown in Figure 5.3.



Socioeconomic considerations
Executive summary (a cautionary note)

2.10 Socioeconomic considerations
(a cautionary note)

These strategies do not take into account socio-economic aspects. Almost every
rural household in India owns a milch animal and often depend on these for the
day to day cash flow and for high quality nutrients for their family diet. Milk is
important, as it supplements an often vegetarian diet which is often imbalanced
for amino acids. Reduction in milch animal numbers would inevitably be at
the expense of the rural poor—the tendancy, with ownership of “high yielding”
animals will be for these to be owned in larger herds in the hands of “rich”
farmers.

Additionally, in developed countries with market economies, improvements
in animal performance have led to reductions in overall animal numbers. If socioe-
conomic considerations prevent similar shifts in animal numbers from occurring in
cases where supplementation is implemented, the full potential to reduce methane
emissions and increase productivity may not be realized, It is expected, however,
that constraints on feed supplies will, over the long term, is likely to force shifts
in animal numbers that are consistent with the experience of market economies.

Thus any suggestion of reduction of numbers of milch animals may reduce
the standard of living of the rural poor in India (and other developing countries);
alternative sources of income would need to be provided along with the devel-
opment strategies envisaged. India already has a policy of decentralisation of

industry to rural areas with large incentives such as suspension of taxation of
profits.

20



List of Figures

3.1

4.1

4.2

5.1

5.2

5.3

5.4

5.5

Graphs illustrating the relatively stressful heat conditions through-
out the year for the tropical and temperate areas ......... 36

Relationship between carbohydrate fermentation and the produc-
tion of VFA, methane and carbon dioxide and microbial cell syn-
thesis 2. ee ee ee ne 48

Relationship between the production of microbial cells (Cell DM)
and volatile fatty acids (VFA) and methane (CH,) in fermentative
digestion in ruminants... 2... ee eee 49

Requirements for ammonia to maximise fermentative digestion in
the rumen and optimise intake of a low quality roughage by cattle 57

Schematic relationship between diet quality (metabolisable energy /kg
dry matter) and food conversion efficiency (g liveweight gain/MJ
ME) 0. ccc cc ete eee eens 64

Effects of improving the efficiency of rumen fermentative activity
on methane production and production of methane per kg gain in
supplemented cattle 2... 2... eee 65

Effects of supplementation and straw treatment on the methane
produced in cattle fed straw that was untreated or treated with
ammonia 2... ee ee 66

Relationship between the metabolisable energy content of a feed
and the methane produced per level of gain ........-.... 67



Executive summary Tables and Figures

Figure 5: this appears later as Figure 5.5

Relationship between the metabolizable energy content of a feed (M/D, MJ/kg)
and the theoretical methane produced per kg gain. The relationship shown by a
broken line is based on the metabolizable energy system in practice in UK (Web-
ster, 1989). The relationship indicated are results from the studies of Perdok et
al., 1988 (o, 0, e); Hennessy et al., 1988, Hennessy et al., 1989 (QO); Saadullah,
1984 (Q) and Wanapat et al., 1986 (A) in which cattle fed straw, straw treated
to improve its digestibility or poor quality hay were supplemented with increasing
levels of bypass protein. (The data are calculated from Figure 4.) Methane pro-
duced per unit of gain was lowest when the efficiency of liveweight gain had been
stimulated by feeding bypass protein.

0.50-
0.455
0.404
0.35-
0.304 -

0.25 as
0.20- _

0.154 A, we
0.10, oD, eK are

0.054
0.00: T T T T T T T
5 6 7 8 9 10 1 12 13
Energy value of diet M/D
(MJ/kg)

Methane production
(kg methane/kg gain)

25



Application of strategic
supplementation: some
important considerations Application of MUB

e it halves the methane production per unit of feed digested
© it is likely to be a vehicle for drugs or chemicals to increase productivity

(e.g. antiprotozoal, antimethane reagents, antihelmintics).

The strategic use of protein meals is important because of their effect on
efficiency of feed utilisation and promotion of growth, which has a much larger
effect on the life time production and therefore methane generation.

8.2 Application of MUB

Although MUB appears to be the best method for supplementing urea/trace min-
erals/macro minerals/vitamins, there are a number of other methods for achieving
the same end result particularly in countries where molasses is unavailable or fully
utilised and therefore unavailable for the purpose. These include:

liquid molasses mixtures fortified with urea/ minerals

e blocks made from clay/minerals/nutrients by pressure

e blocks made by pressure from any raw materials

e blocks improvised from any ingredients (e.g. recently blocks were produced
from a seed pod of a tree legume with added urea/minerals and cement)

e dry supplements which are attractive to stock (e.g. salt, with which the
ingredients can be mixed

8.3 Availability of bypass proteins

There are a large number of “naturally” occurring protein meals that are rich
in bypass protein. These are largely the byproducts of the edible oil industry.
The rationale behind this is that in an oil extraction process using either pres-

94



Part 7

Consequences of
widespread application of
feeding

and breeding in India

Part 7 outline: Strategic feeding of ruminants in India has important flow-on ef-
fects that may allow additional improvements in production. The better feeding
allows improved genotypes for milk production to be more widely distributed
and may allow multipurpose animals to be used more effectively leaving the
way clear for a reduction in cattle or buffalo population densities. Reduction
in large ruminant densities are seen as the most effective means of reducing
methane emissions on a world wide basis, provided productivity per animal is
increased.

7.1 Milk production

The policy makers of NDDB of India have a clear perspective on feeding and
breeding. Combining the principles of feeding discussed in this presentation with
improved genotype (usually 50:50 indigenous: Friesian) can have a dramatic effect
on milk production in India.



Calculated amounts of methane produced per unit of milk produc-
tion in unsupplemented (fed traditionally) or supplemented (new
feeding systems) cows in India with moderate levels of production.

Colour plates to illustrate the ingredients of the molasses urea
blocks, the manufacturing plant, blocks in slab form and ready
for sale (Kunju, 1989)

Colour plates to illustrate the method of presentation of MUB to
cattle and buffaloes

Effects of increasing supplement levels on milk yields of cows fed
ammoniated straw

Average 305 d lactation yield of different breeds of cattle in the
first five lactations fed on tropical forage and supplements ... .

Age at first calving of cows of different breeds fed tropical forages
and supplemented with bypass protein and MUB in India

Case study of the implementation of feeding strategies based on
bypass protein and MUB in Kiara district of India



Application of strategic
supplementation: some
important considerations Introduction

In India the immediate economic returns through the system of marketing
of milk, particularly in cooperatives, readily convinces farmers of the benefits
of supplements. It is the objective of the NDDB to make available the supple-
ments for feeding to all animals within the cooperatives which will eventually
then be accessible to 6-8 million milch animals. The same strategy is also the
recommendations of the Technology Mission to the Indian Government.

It is, however, difficult to convince farmers to use blocks and/or protein
feeds under the following conditions:

where the basal feed resource is so poor or of low availability that responses
are not easily seen. It is difficult, for instance, to recognise a 10-20% in-
crease in milk yield in a buffalo producing 1 litre of milk per day and this
has mitigated against the use of MUB by small farmers. uo

where there is no economic return for a considerable time; for example,
where animals are sold only at maturity or income only begins when milk
is produced. Most small farmers have no cash flow to allow the purchase of
supplements.

where the young female is being grown-out for lactation, even though the
age at puberty may be reduced by several years, this is difficult to commu-
nicate to farmers and even farmers with cows of high genetic potential often
fail to provide them the supplements needed to improve growth. (This also
applies to bullocks being grown out for draft.)

where numbers of animals are more important than total liveweight (as in
parts of Africa or with nomadic people in India).

where the cattle are owned by nomadic people.

The problem is one of convincing the enormous numbers of small farmers
of the benefits of supplementation and providing the supplements at low cost
(with possible deferred payments). The molasses/urea block alone, when given
to cattle and buffalo on crop residue feeds does not result in spectacular increases
in productivity; whereas the use of bypass protein has a large effect and this is
again improved where both MUB/bypass protein meals are given together. -

From the point of view of this review, the establishment of MUB supple-
mentation could be important for two reasons:

93



Application of strategic
supplementation: some
important considerations

Education

8.8 Education

The steps to be taken to ensure application must be

¢ to make generally available for purchase by farmers, a multinutrient block
and a protein meal rich in bypass protein

© to educate personnel at ail levels of the industry, from University teachers
through to extension officers and farmers

© to provide markets for the products as incentives to use the supplements.

The emphasis in nutrition must be away from the traditional dogma to the
new balanced nutrient approach (see Preston & Leng, 1987).

The steps to educate must include:

© production of postgraduate text books (Preston & Leng, 1987)

e production of more applied text books for undergraduate students and ed-
ucated farmers

¢ production of simple texts that can be understood by farmers
e highly simplified word/picture texts for illiterate farmers

e education of village children in the simple application of these technologies.
Most children in India, for example, have some education to 12-years of
age. Most of them live in households that own a cow or a buffalo but the
nutrition of these animals is not considered in the curriculum.

® massive educational programmes drawing on all forms of media, from videos
through to lectures at the village level

98



Modifying methane production Stimulating animal production rate

5.2.2 Supplementation

It is now well established that moderate to high levels of production can be
achieved in ruminants given low quality pasture or straw based diets by providing
minerals and urea and optimal inputs of a protein that escapes fermentation in
the rumen but which is digested in the intestines to augment the nutrients arising
in the rumen.

a The key roles of supplements (Leng et al., 1987) may be summarised as
follows:

© urea increases the efficiency of fermentative digestion in the rumen stimu-

1 lating digestibility and feed intake.

I~ @ urea supplementation through its effects on fermentative digestion ensures
sufficient nutrients in balanced amounts to allow the birth of a viable calf
or lamb. :

¢ supplementation with a protein meal that largely bypasses rumen fermen-
tation in addition to urea has the following effects. It provides a better
balance of nutrients to the animal and increases live-weight gain and effi-
ciency of feed utilisation in (i) young animals, (ii) pregnant ruminants and
(iii) lactating animals. In young animals age at puberty is decreased by
strategic supplementation with a protein meal during the dry season or on
straw based diets.

It markedly increases conception rate and, by implication, decreases inter-
calving interval in mature cows with calves at foot and grazing.

Supplementation of genetically high yielding cows given tropical forages
and/or straws with a MUB plus a 30% protein meal rich in bypass protein at a
rate of 350 g/litre of milk has resulted in milk yields closely similar to that of
cows on concentrate based diets in developing countries (NDDB report, 1988).

Cattle (and buffaloes?) that are subjected to periods of low nitrogen nu-
trition during their early life may be stunted permanently so that their mature
weight is often 100 kg less than that of animals that have received bypass protein
during these periods.

61



Improved animal production rate
Modifying methane production and methane production

Figure 5.5: Relationship between the metabolizable energy content of a feed (M/D,
MJ/kg) and the theoretical methane produced per kg gain. The relationship shown
by a broken line is based on the metabolizable energy system in practice in UK
(Webster, 1989). The relationship indicated are results from the studies of Perdok
et al., 1988 (0, 0, #); Hennessy et al., 1983, Hennessy et al., 1989 (@); Saadullah,
1984 (Q) and Wanapat et al., 1986 (A) in which cattle fed straw, straw treated
to improve its digestibility or poor quality hay were supplemented with increasing
levels of bypass protein. (The data are calculated from Figure 5.2.) Methane
produced per unit of gain was lowest when the efficiency of liveweight gain had
been stimulated by feeding bypass protein.

0.50-
0.45-
0.40-
0.354
0.30-
0.25- ~
0.20- _

0.15+ AW, mL
0.10 FB, oA. eee

0.05-
0.00:

lon

producti

(kg methane/kg gain)

Methane

5 6 7 & 9 10 11 12° 13
Energy value of diet M/D
(Mu/kg)

67



Executive summary

concentrations. Managed livestock, and in particular, large ruminant animals,
are important contributors to the increasing abundance of atmospheric methane,
accounting for on the order of 15 to 20 percent of annual methane emissions.

Of the approximately 1.5 billion large ruminant equivalents (i.e., cattle, buf-
falo, sheep and goats) in the world, the largest proportion of these are supported
on relatively poor feeds particularly (but not only) in developing countries and
therefore grow and produce at variable but relatively low rates. It is probable
that 80% of the whole global herd could come into such a category.

Improved nutritional management of these ruminant animals, e.g., through
supplementation, is expected to lead to increased productivity and will generally
reduce methane emissions per unit of product. Provided that the markets for the
products do not expand, improved animal productivity will lead to reductions in
methane emmissions from these animals.

This report provides
@ essential background information on the basic chemistry of fermentative
digestion in the rumen

@ the reasons for specifying supplementation as an important and practical
means of reducing methane emissions from ruminant animals

@ the likely reduction in methane from ruminants through supplementation

@ the strategy needed for application in developing countries where large num-
bers of low producing animals are found

@ acase study of application of supplementary feeding in India

© some issues required to obtain wide scale acceptance of the feeding practices
in those countries where livestock population densities are high but at a
subsistence level of production.

Application of strategic supplementation to cattle fed poor quality forage
could reduce methane production per unit of product by 25-75%.

12



Application of strategic
supplementation: some
important considerations Protection of oil seed meal residues

sure or solvent, a considerable amount of protein is heat denatured and becomes
insoluble in the rumen. Undoubtedly, there is considerable variation between
meals produced by differing treatments but cottonseed meal has been found to
be consistently rich in bypass protein.

The oil seed meals have been a traditional export commodity for many
developing countries and these exports are important to their economies because
they are a source of “hard” currency. However, it will be important to retain
these meals within a country in the future.

There are a wide variety of oil seed meals within developing countries, in-
cluding the meals from cottonseed, niger (noug), linseed, sunflower, safflower,
guar (cluster bean), groundnut and soyabeans. The content of bypass protein
in these feeds varies with processing methods and source of protein. In general,
cottonseed and linseed meal are very good sources of bypass protein (50-75% of
the protein is protected) whereas the others vary from very little to about 50%
protection (see Leng et al., 1977). Undoubtedly it would be biologically more ef-
ficient to protect those protein meals low in bypass protein by simple procedures.
There is a considerable need for assessment of the suitability of the available
protein meals in a country.

8.4 Protection of oil seed meal residues

There are a number of methods for protection of protein meals to allow them to
escape degradation in the rumen when they are fed to ruminants. For developing
countries, there are possibly three which may be applicable: treatment with (1)
formaldehyde, (2) heat or (3) xylose and glucose or heat.

Formaldehyde has been outlawed in most countries because of the potential
formation of gaseous carcinogens. Heat treatment is often too expensive but the
recent developments with xylose treatment has great promise and may be the
method of choice. This is especially important as xylose can be very easily and
inexpensively produced in a crude form by acid or alkaline hydrolysis of bagasse
or other fibrous feeds. A major, useful source of xylose is the sulfite liquor from
the paper industry which contains 5% xylose.



Improved animal production
Executive summary and methane production

2.6 Improved animal production
and methane production

The effects of supplementation and of treatment of straw on the generation of
methane per unit of feed intake and per unit of live-weight gain on milk production
are shown in the Figures 1, 2 and 3 at the end of this Section. This indicates that a
very large decrease in methane production from ruminants in developing countries
can be achieved provided that animal numbers are decreased as productivity per
animal is increased (see p. 20 Socioeconomic considerations (a cautionary
note)). It also presupposes that disease/parasitism are not constraints or are
controlled by good animal] health management.

The new feeding systems, when applied in tropical countries, have given
some remarkable responses. In general, the metabolisable energy content of a diet
fails to predict liveweight gain of cattle on straw based diets that are supplemented
with critical nutrients. This is shown in Figure 4 at the end of this Section.

At the same time, cattle on “poor quality forages” that are supplemented
with critical nutrients, grow much more efficiently than predicted by feeding stan-
dards. They also produce only the same methane per kg liveweight gain as an-
imals on high quality feeds (e.g. barley concentrate mix). This occurs despite
considerable differences in growth rates which may be twice as fast on the high
quality feed vs. the poor quality forage with supplements (Figure 5, end of this
Section).

The foregoing discussion of the potential of supplements to increase methane
is based on scientific principles, particularly the effects of improving microbial
growth efficiency by supplementation. Whilst there is considerable data which
supports the general thesis, there is no work that has set out to measure changes
in methane production with improving microbial growth efficiencies. Research is
needed in this area.



Digestive physiology of
ruminants: implications for
improving animal production

from poor quality forages Fermentative efficiency in the rumen

growth in the rumen. The efficiency of microbial growth (that is, the amount of
microbial biomass available for digestion in the intestines per unit of digestible
carbohydrate entering the rumen) largely determines the proportion of digested
energy that is lost as methane.

Methane production accompanies the formation of acetate or butyrate,
whereas the conditions that promote the synthesis of microbial cells and pro-
pionate production also lead to reduced methane production.

4.3.1 Meeting the requirements
for efficient microbial growth in the rumen

On most diets based on crop residues and low-digestibility forages, the primary
limitation to the growth of rumen micro-organisms is probably the concentration
of ammonia in rumen fluid (with secondary considerations for deficiency of min-
erals, particularly sulfur, phosphorus and certain trace minerals). Ammonia must
be above a critical level for a considerable period of the day to ensure a high rate
of microbial growth, rate of digestion and feed intake. The level of ammonia that
supports the optimal population of micro-organisms in the rumen, and therefore
maximum digestion, will vary among diets. In general the ammonia level should
be above 200 mg nitrogen/litre (Perdok et al., 1988).

It must be stressed, however, that any nutrient required in the growth of
microorganisms that is deficient in a diet will result in low microbial cell yield

relative to VFA and this will increase methane generation per unit of feed con-
sumed.

Deficiencies of ammonia and a number of trace and macrominerals in the
rumen of animals on poor quality forage based diets can be corrected under ap-
plied conditions by using a molasses/urea multinutrient block lick (referred to as
MUB) (see Leng & Preston, 1984; Leng & Kunju, 1989). Under tropical con-
ditions, sodium, sulfur, magnesium, phosphorus and a number of trace minerals
(copper, cobalt, zinc etc.) are the most likely limiting nutrients.

46



Consequences of
widespread application of feeding
and breeding in tndia Overall conclusions

7.6.1 Methane production by cattle fed high v. low qual-
ity forages

A major conclusion of this review is that, in the tropics and with cattle fed on a
basal diet of poor quality forage, (but with supplements to balance the nutrients
to requirements) the production of methane per kg gain is about the same as that
on high quality feeds. This is surprising since growth rates on the supplemented-
poor quality feeds are often half that on the high quality feeds. It is possible that
this difference arises from climatic differences.

The need to oxidise more nutrients to maintain body temperature in cold
climates as against hot/humid climates could account for some of the difference.
However, it seems more realistic that “energy requirements” are overestimated
by traditional feeding standards. Therefore, more widespread use of protein meal
supplements to ruminants will improve efficiency of use of even high digestibil-
ity/high concentrate feeds. There is, therefore, scope for a significant reduction
in methane generation by ruminants in the industrialised countries.



introduction

The observed increase in the atmospheric abundance of methane must be
caused by an imbalance in the sources (i.e., emissions) and sinks (i.e., destruction
and uptake) of methane. The mechanisms leading to these observed increases in
methane are believed to be: (1) increases in emissions; and (2) possibly decreases
in its rate of destruction. The major anthropogenic sources of methane emissions
are: animals (primarily managed ruminant livestock); rice cultivation; biomass
burning; oil and gas production and distribution; coal mining; landfills; and waste
management. Emissions from each of these sources have increased substantially
in the last two or three centuries.

The increased abundance of methane will have important impacts on: the
stratospheric ozone layer; background levels of tropospheric (i.e., ground-level)
ozone; global climate. Estimates are that methane will contribute about 20 per-

cent of the expected global warming from the greenhouse effect, second only to
carbon dioxide.

To address the increasing concentrations of methane and other trace gases,
international efforts have begun to identify opportunities for reducing anthro-
pogenic emissions. A recent workshop sponsored by the Intergovernmental Panel
on Climate Change (IPCC) found that opportunities exist to reduce methane
emissions from managed ruminant livestock. Achieving such reductions in con-
cert with reductions from other key sources will help to stabilize global methane
concentrations. Although there is uncertainty in the level of emissions from var-
ious individual sources, it is believed that a combined reduction of about 10 to
20 percent in anthropogenic emissions will be sufficient to stop the increase in
methane concentrations.

Ruminants produce 15-20% of the total methane generated; of the enteric
source of methane, cattle contribute nearly 70%. The methane is generated
largely in the fermentative digestive system (the rumen).

Most of the world’s cattle and buffaloes (Table 3.1) are in the developing
countries in Africa and Asia where they are largely fed on poor pastures, crop
residues and agro-industrial byproducts.

The large populations of cattle in South America, parts of the USA, Aus-
tralia and New Zealand are largely supported on pasture land not easily farmed or
of inherent low fertility. These systems use only low inputs and usually little or no



Executive summary Methane production by ruminants

2.2 Methane production by ruminants

Ruminant animals (cattle, deer, goats and sheep) are estimated to produce 65-
85 Tg of methane annually (1 Tg = 1 teragram = 10)? grams = 10° kilograms
= 10° metric tons) or 15-25% of the estimated global methane production (400-—
600 Tg). Most of this is attributed to cattle, of which the vast majority are
situated in developing countries.

The objectives for reduction of methane production, apparent when dealing
with ruminants, are to:

e increase the efficiency of feed utilisation in fermentative digestion

© modify intestinally digestible feed components (protein and starch) to avoid
fermentative digestion

e increase animal product turnoff and satisfy human demands for ruminant
products from fewer animals (i.e., reduce the numbers of low producing
animals, particularly in the heavily populated countries)

e supplement diets with natural products or chemicals that inhibit methano-
genesis irrespective of whether this increases productivity and/or profitabil-
ity

Other possibilities include the development of methane oxidising organisms
or other hydrogen sinks in the rumen using genetic engineering.

The first three objectives are compatible and the first two automatically
support the third. Manipulation of methanogenesis in the ramen may be more
applicable in the developed countries with large automated feedlots.

The use of supplements and in particular molasses/urea multinutrient blocks
in developing countries could form a vehicle for chemicals used for rumen ma-
nipulation. Where there is easy access to animals fed compounded rations the
chemicals could be directly added to the diet.



_ Stimulating rumen
Modifying methane production fermentative efficiency

Figure 5.1: Requirements for ammonia to mavimise fermentative digestion in the
rumen and optimise intake of a low quality roughage (Perdok et al., 1988). Urea
was infused continuously into the rumen to provide a constant supply of ammonia

‘ Intake (kg/d) Digestibility (%)
60

| Max. digestibility
Max. intake

100 200 300

200 300
Rumen ammonia (gN/I)

Rumen ammonia (gN/I)

5.1.4 Supplying deficient micronutrients for microbes

It has been accepted that the optimum levels of ammonia in the rumen for maxi-
mum digestion was about 50-60mg N/litre. However, in recent studies, increasing
rumen ammonia levels by infusing urea into the rumen, increased digestibility of
straw in cattle until ammonia levels reached 80mg/litre. Feed intake continued
to be stimulated until NHs levels reached 200mg NHs/litre (Figure 5.1, see also
Boniface et al., 1986). This indicates that the amount of urea required in straw
based diets has been underestimated in the past.

Ammonia in the rumen can be supplied along with a number of potentially
deficient microbial nutrients by:
¢ supplying a mixture of molasses (a concentrated plant juice) and urea in

the feed;

@ feeding chicken manure;





Consequences of
widespread application of feeding
and breeding in India Draft power—body size

7.4 Draft power—body size

The extremely smal] bullocks (150-250 kg liveweight) seen in developing coun-
tries are mostly a result of nutritional stunting in early life. This has been shown
by researchers in Australia. Applying the principles of balancing nutrition during
periods when protein is deficient in the basal feed in early life has resulted in a
difference in mature size of cattle of 80-100 kg (Hennessy, 1986). Similarly a com-
parison of breeds in Africa under ranch conditions (where nutrition is moderate
and the young animal has access to milk for up to 12 months), or in the herds of
traditional farmers (where nutrition is nearly always poor and the young animal
often competes for milk with humans, i.e., they are often protein deficient) have
demonstrated similar results.

The need for bullocks can be contracted by producing larger bullocks, bet-
ter implements and by feeding to promote greater draft capacity. The simple
application of molasses/urea blocks to bullocks increases straw intake, the nutri-
ents extracted from that straw and the efficiency with which those nutrients are
used. This, in turn, improves health and work capacity. The replacement of two
bullocks by one could reduce the feed requirements for draft power by more than
25%. The rationale for this is that a working bullock probably needs 2.5% body-
weight as forage; so two 400 kg bullocks consume 20 kg of feed. If a single bullock
(500 kg LWt) was fed a molasses urea block it may be able to extract 30-50%
more nutrients from the forage (which is usually straw) and could eat, say, some
15 kg forage. Supplementation with a molasses urea block will halve methane
production in the rumen. The net reduction of methane production on feeding
MUB and halving numbers would be of the order of 60% from the national herd
of bullocks.

7.5 Population densities of dairy animals

The net effect of strategic feeding to balance nutrients in the available resources
for dairy animals, and better feeding of bullocks is to reduce the needed number
of mature animals from 275 million to 112 million, with, say 26 million young
stock in the process of maturation.

89



Improving ruminant production

Introduction in developing countries

3.5 Improving ruminant production
in developing countries

Livestock-keeping in the Indian sub-continent and within Africa is dominated by
the need for draft power. The majority of agricultural land (approx. 90%) is still
worked with bullocks. Most farmers in India keep cows in order to produce male
offspring to be reared as draft bullocks (Kurup, 1989).

However, with the inception of the milk co-operatives in India, specialised
milk production with high yielding crossbred cows and selected buffaloes is in-
creasing.

Buffaloes, on the other hand, are kept largely for milk production and ma-
nure generation for fuel purposes. Buffaloes are rarely used for draft power except
in wet rice production and most males are allowed to die in the first few weeks
of life (Kurup, 1989).

There are some 75 million bullocks (bovine) in India with an annual replace-
ment rate of 10 million. These replacements are produced by some 40 million
nondescript cows, which probably calve once every two years and average 500 to
600 kg milk per lactation.

There are strong reasons for arguing that the most economic way of meeting
the increasing demand for milk, meat and draft animals is through improvement
of traditional livestock production systems based on multipurpose animals, rather
than through development of specialised milk, meat and draft animals (see Pre-
ston & Leng, 1987).

The bases for this argument are as follows:

e The growing need for larger numbers of draft animals in some developing
countries makes it increasingly necessary to use milch animals for draft.
Also, decreasing farm size in some countries, notably Bangladesh, is forcing
farmers to use cows for work. Draft animals will often increase farm output
several fold by increasing the area that can be put under crops and farmed
by a family.



Application of strategic
supplementation: some Sources of bypass protein
important considerations in countries with no oilseed industries

The treatment method is to spray the xylose solution on to the protein meal,
heat it to 200°F for 2 hours (Lewis. et al.,1988). The benefits of such treatment
is illustrated by the data in Table 8.1.

Table 8.1: Effects on liveweight gain of supplementing a basal forage/concentrate
based diet with soyabean meal or soyabean meal treated with sulfite liquor at 200° F
for 2 hours (Lewis et al., 1988)

LWt gain
(e/4)
No supplement 591
+ 7% soyabean 673

+ 9% soyabean + 10% SL 823
+ 8% soyabean + 5% SL 841

8.5 Sources of bypass protein
in countries with no oilseed industries

Some countries have no oil seed meals and may not be able to import such
materials. One of the options is to produce high protein sources locally and
to treat these to give optimum protection, e.g. crops such as lupins, peas, beans
or other high protein seed crops may need to be grown and processed for the
ruminant industries. The methods to be used may be similar to that suggested
above for soyabean meal (i-e., heat/xylose treatment).

A further possibility is to grow high protein legumes (trees or forages) from
which the leaves are harvested, treated and distributed for use by farmers.

96



Strategies for improving
: animal production/reducing
Introduction greenhouse gas emissions

to the specialized non-native milking herds, the crossbreds usually have greater
resistance to disease and other environmental constraints. The appropriate strat-
egy for each country, however, should be adjusted according to the available feed
and technological resource.

3.5.2 Specialised beef cattle production

Unlike specialised dairy cows, specialised beef cows are inefficient, especially when
the feed offered could support more productive systems. This is because their
productivity is governed by their reproductive rate, which is always less than
one offspring per year and considerably inferior to that of other meat-producing
species such as pigs, poultry, sheep, goats and rabbits.

Highly specialised ruminant production systems that produce only meat
(and hides) have developed largely in countries where population densities are low
and land areas are large. In developing countries specialist beef herds are largely
confined to government stations and large commercial ranches. Specialised goat
and sheep production can be very important in the Moslem countries.

3.6 Strategies for improving
animal production/reducing
greenhouse gas emissions

Any strategy for improving livestock production must fit within a country’s
development-framework and now must consider the implications for global warm-
ing (i.e., the Greenhouse Effect). A best bet approach for most countries will be
realised through an integrated approach that employs multipurpose crops, multi-
purpose animals, with residues and byproducts useable as feed or fuel or capable
of being recycled back to the land. Inevitably such developments will lead to
increased production per animal per life time and reduction in overall animal
numbers as the market requirements become saturated.

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