NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
S. C. RAY 247
Table III shows that, whereas the intensities of phosphatase excretion
amongst the different animals per unit of dry food varied within a compara-
tively narrow range, the producing animals, namely goats 2, 3 and 4 excreted
significantly more units of phosphatase per kilogram of body weight than
goat 1, which was an adult non-producing animal. If one accepts the view
that the enzyme phosphatase excreted in faeces is of endogenous origin, it
appears that, when the nature of the feed remains the same, the activity of the
enzyme is increased simultaneously with the higher rate of productive meta-
bolism, in which increased amounts of phosphorus and calcium naturally have
to play their part.
In experiment 2, as the quantity of faeces voided diminished, the number
of absolute units of phosphatase similarly declined. More significant in this
connection is the fact that under the condition of effective fasting, phosphatase
excreted per gram of dry matter in faeces was also greatly reduced. From
an average of 23 units, it was reduced to 6.0 and 8.5 units respectively for
goats 1 and 2 during the last four days of fast and 5.1 and 5.2 units respectively
for goats 3 and 4 during the last seven days of fast. This finding is contrary to
what Smith, Howat and Ray [1938] observed in the case of phosphatase in
cow's milk. In milk, with the progress of the fast, although the number of
absolute units of phosphatase was greatly reduced with the reduced yield, the
units of phosphatase per 100 ml. of milk was very considerably increased to-
wards the end of the period. On the other hand the phosphatase in blood-
serum, under the fasting condition of the present experimental animals, as
well as of sheep and of milch cows, showed definite decrease as could be evi-
denced from the data presented by Morris and Ray [1939]. These results tend
to show that the activity of the enzyme from different sources does not follow
the same course under the same physiological conditions. The milk phospha-
tase is perhaps independent of the general cellular activity, and is specifically
connected with milk secretion alone.
The lowered activity of faecal phosphatase under the fasting condition
can be explained by Cayla's theory, according to which, bile is the controlling
factor in the secretion and activation of intestinal phosphatase. Since it is well
known that during an effective fast, the biliary activity is greatly reduced,
the lowered activity of phosphatase may be due to diminished bile secretion.
The lowered activity may also be ascribed to the general inhibition of the
cellular activities brought about by inanition.
SUMMARY
A method of measuring the activity of phosphatase in faeces has been
described.
A preliminary study of the faecal phosphatase excretion during normal
metabolism and during a prolonged fast shows that under normal conditions,
animals excrete a significant amount of this enzyme in their faeces but that
this excretion is considerably reduced during a prolonged fast.
ACKNOWLEDGEMENTS
The experimental work described in this paper was carried out in the
physiological laboratory, Hannah Dairy Research Institute, Scotland. The
248
Phosphatas in Faeces
author is grateful to Dr N. C. Wright, Director of the Institute, for giving him
facilities for carrying out this work. The author also desires to acknowledge
his indebtedness to Dr K. C. Sen, D.Sc., for his helpful criticism in the prepara-
tion of this paper.
REFERENCES
Bodansky, A (1932-33). J. Biol. Chem. 99, 197 ; 101, 83
Cayla, J. (1935). Le Progres de medicine, 43
Duckworth, J. (1935). Biochem. J. 29, 658
Duckworth, J. and Godden, W. J. (1941). Biochem. J. 35, 16
Morris, S. and Ray, S. C. (1939). Biochem. J. 33, 1217
Smith, J. A. B., Howat, G. R. and Ray, S. C. (1938). J. Dairy Res. 9, 310
Verzar, F. (1936). ' Absorption from intestine' 247
THE MAYNARD GANGA RAM PRIZE
Applications are invited for the award of the Maynard-Ganga Ram
Prize of Rs. 3,000 for a discovery or an invention or a new practical method
which will tend to increase agricultural production in the Punjab on a paying
basis. The prize is open to all, irrespective of caste, creed or nationality and
Government servants are also eligible for it. Essays and theses are not
accepted.
The prize will be awarded for something practically achieved as
a result of work done after the prize was founded in 1925. Competitors in
their applications must give a clear account of the history of their invention
or discovery and must produce clear evidence that it is the result of their own
work. In the case of an improved crop details of parentage, evolution and
history and a botanical description are necessary.
The Managing Committee reserves to itself the right of withholding or
postponing the prize if no satisfactory achievement is reported to it, or to
reduce the amount of the prize or to divide it if the quality of the entries
justify this decision.
Entries should reach the Director of Agriculture, Punjab, Lahore, not
later than 31st December 1942.
261
GIPD—S1—178 IC of AR—10-10-42—500.
ORIGINAL ARTICLES
THE NUTRITIVE VALUE OF ALKALI-TREATED CEREAL
STRAWS
BY
K. C. SEN
S. C. RAY
AND
S. K. TALAPATRA
Animal Nutrition Section, Imperial Veterinary Research Institute, Izatnagar
(Received for publication on 3 August 1942)
(With one text-figure)
T HE problem of a better utilization of crude fibre from coarse feeding
stuffs has for long been a subject of study and, some years ago, Mangold
[1934] drew attention to the number of attempts made by German workers
to treat straw by chemical and other methods so as to increase its digest-
ibility and utilization. He mentioned the ' Lehmann process ' of alkali
treatment of straw which produced a substance of greatly increased
fibre digestibility. In Lehmann's process [Lehmann, 1900] 200 lb. of
straw were boiled in large iron boilers with 40 gallons of water con-
taining 4 to 8 lb. of caustic soda for six hours at a pressure of four to five
atmospheres. After this, the product was washed with water until free from
alkali and then well pressed. By this process, the digestibility of straw was
found to be increased by about 50 per cent. Although the commercial utiliza-
tion of this and other similar methods eventually proved to be too expensive,
a large-scale production of treated straw was attempted in Germany during
the last war when an acute fodder shortage was experienced. In England,
Godden [1920] tried to simplify the process by soaking chopped straw over-
night in a 1.5 per cent solution of caustic soda. The treated straw was then
removed and the excess of caustic soda allowed to drain away, after which
the material was placed in a vertical container and heated in a current of
steam, the whole mass being kept at boiling point for about an hour. The
substance was then allowed to cool and the condensed water drained off.
During the steaming, sufficient organic acids were liberated from the straw
to neutralize the absorbed alkali and consequently no further washing was
required. With this treatment, Godden showed that the digestibility co-
efficient of crude fibre in oat straw increased from 60.1 to 87.4 and that of
nitrogen-free extract from 39.6 to 62.9. The consequent starch equivalent
(S.E.) value was found to increase from 20.6 in the original straw to 36.9
in the treated straw. During the treatment, however, 20 per cent of the dry
matter in the original straw was lost. When this loss was taken into account
the actual increase in S. E. proved to be about 43 per cent.
About the same time as this work was being carried out in
England, Beckmann [1919] in Germany introduced a new technique in
which no heat treatment was required. Furthermore, it was shown that
an alkali solution weaker than 1.5 per cent was effective and that the time of
263
A 2
266
The Nutritive Value of Alkali-treated Cereal Straws
The chopped material was thoroughly mixed and 170 gm. of oat and 200 gm.
of wheat and paddy straws respectively were weighed out in separate en-
amelled basins. To the straws, 8 times their weight of 1.25 per cent caustic
soda solution was added and the contents of the basins thoroughly mixed
with a flat wooden ladle. The straws were soaked in alkali for about 20 hours.
The wet straw was then squeezed against the side of the basin and the alkaline
liquor poured off into a separate vessel. About 45 to 50 per cent of the
volume of the original liquor could thus be recovered. Tap water was then
added to an amount a little over the volume lost in soaking. The ' alkaline
straw ' was thoroughly turned over in this fresh water and after standing for
15 minutes, as much as possible of the wash water was separated from the
straw and poured into the vessel containing the original liquor. The com-
bined volume of the liquor and wash water was approximately the same as that
of the alkali solution used for treating the quantity of straw weighed out.
The strength of the alkali in the combined mixture of original liquor and wash
water was determined. After the collection of the first wash water, the treat-
ed straw was transferred to a thoroughly cleaned laboratory sink which was
fitted with an overhead water tap. The outlet passage of the sink was covered
with a wire gauze netting and water was continuously sprinkled over the mass
of straw till the wash water was no longer alkaline. The treated straw was
then dried and analysed. It may be mentioned that the dry treated straw
of all three kinds was markedly changed in colour and texture, the products
being distinctly yellow, softer to the feel and finer in texture than the original
straws.
The results and discussion
(a) The alkali treatment of the straws and their subsequent washing
with water to remove the alkali caused a significant loss in the dry matter
TABLE I
Effect of alkali treatment on the dry matter of straws
Wheat straw . .
Oat straw . .
Paddy straw . .
Amount taken
Air-dry
(gm.)
200
170
200
Oven-dry
(gm.)
184.1
159.8
180.0
Amount obtained,
after alkali treat-
ment
Air-dry
(gm.)
149.4
118.0
152.0
Oven-dry
(gm.)
136.0
106.2
135.3
Per cent dry
matter
Recover-
ed
74
66
75
Lost
26
34
25
content, as will be seen from the data presented in Table I. This loss in
dry matter was least in the case of paddy straw and little more in that of
wheat straw. In oat straw, the loss was 34 per cent, which was consider-
ably higher than in the other two types. Working with the same straw,
K. C. SEN, S. C. RAY AND S. K.
TALAPATRA
267
Godden [1920] recorded a loss of 33.5 per cent, when the straw was treated
with 1.5 per cent caustic soda solution and subsequently washed with water
to free it from alkali. The loss in dry matter, as will be shown later, could
be accounted for by the individual losses sustained by all the constituents
except crude fibre. The two constituents which contributed most to the
loss in dry matter were nitrogen-free extracts and total ash.
(b) The percentage composition of straws were significantly altered
after the alkali treatment. The change in the composition is shown in
Table II.
TABLE II
Percentage composition on dry basis
Wheat straw No. 1 .
Oat straw . .
Paddy straw No. 1 .
Wheat straw No. 2 .
Paddy straw No. 2 .
{ Untreated . . .
Treated . . .
{ Untreated . . .
Treated . . .
{ Untreated . . .
Treated . . .
{ Untreated . . .
Treated . . .
{ Untreated . . .
Treated . . .
Crude
protein
2.69
1.82
2.56
1.92
2.64
2.20
2.02
1.21
2.98
2.51
Ether
extract
0.47
0.38
1.47
1.07
1.21
1.03
0.98
0.96
0.83
0.60
Crude
fibre
39.43
52.00
34.20
53.47
34.79
46.00
39.95
57.00
40.43
56.03
Total
ash
10.17
8.81
16.94
5.28
18.43
14.89
10.48
3.80
8.57
7.25
N-free
extracts
47.24
36.99
44.83
38.26
42.93
35.88
46.67
37.03
47.19
33.61
In the different straws, although the alteration in the composition of the
constituents was not similar, the change followed a uniform course in all
cases. Thus the percentage of crude protein, ether extract, total ash and
nitrogen-free extracts was lowered and that of crude fibre increased. Crude
fibre, unlike the other constituents, was apparently not affected by the alkali
solution. This will be more clearly evident from the data presented in Table
III, in which the recovery of the constituents has been shown on the basis of
the total dry matter obtained after the treatment.
TABLE III
Recovery of nutrients after alkali treatment
Wheat straw No. 1 .
Oat straw . .
Paddy straw No. 1 .
Total amount before treatment
{ Total amount after treatment
Per cent recovery after treat¬
ment
Total amount before treatment
{ Total amount after treatment
Per cent recovery after treat¬
ment
Total amount before treatment
Total amount after treatment
{ Per cent recovery after treat¬
ment
Crude
protein
4.95
2.47
50.0
4.09
2.04
50.0
4.75
2.98
62.7
Ether
extract
0.86
0.52
60.5
2.35
1.14
48.5
2.18
1.39
63.8
Crude
fibre
72.59
70.72
97.4
54.65
56.78
103.9
62.62
62.14
99.2
Total
ash
18.72
11.98
64.1
27.07
5.61
20.7
33.17
20.15
60.7
N-free
extracts
86.97
50.31
57.8
71.63
40.63
56.7
77.27
48.55
62.8
268
The Nutritive Value of Alkali-treated Cereal Straws
It may be observed from Table III that all the constituents suffered loss
after the alkali treatment except the crude fibre. In fact, the crude
fibre could be almost quantitatively recovered after the treatment. From
the standpoint of nutrition, the loss sustained in crude protein and ether
extract was relatively unimportant, as these constituents in straws were
poorly supplied and only a little or none of these were actually digestible.
The loss in nitrogen-free extracts (N.F.E.) was, however, important, as the
utility of straw as a food for herbivorous animals is mainly dependent upon
its crude fibre and N.F.E. contents (i.e. its moiety of total carbohydrates).
The data of the present experiment, however, show that the reduction in the
percentage composition of N.F.E. in the alkali-treated straw was more than
compensated for by the rise in the percentage of crude fibre. In fact, the total
carbohydrates per 100 lb. of dry matter were better provided in alkali-treated
straw than in the original untreated straw, as will be evident from the data
presented in Table IV.
TABLE IV
Total carbohydrates in straws
Wheat straw . . . . .
Oat straw
.
.
.
.
.
.
Paddy straw . . . . .
Per cent total carbohydrates
Untreated
86.67
79.03
87.62
Treated
89.12
91.73
89.64
The effect of alkali treatment on the composition of minerals in wheat
and paddy straw is shown in Tables V and VI.
TABLE V
Percentage composition of minerals on dry basis
Wheat straw No. 1
Paddy straw No. 1
{ Untreated .
Treated .
{ Untreated .
Treated .
Silica
5.29
5.79
12.80
11.64
Soluble
ash
4.88
3.02
5.63
3.45
Calcium
0.20
0.37
0.29
0.49
Magne-
sium
0.13
0.17
0.26
0.34
Potas-
sium
1.13
0.34
2.51
0.87
Sodium
0.07
0.59
0.04
0.96
Phospho-
rus
0.09
0.06
0.12
0.08
Chlorine
0.009
trace
0.170
0.006
K. C. SEN, S. C. RAY AND S. K. TALAPATRA 269
TABLE VI
Recovery of minerals after alkali treatment
Wheat straw No. 1
Paddy straw No. 1
Total amount
before treat-
ment
Total amount
after treat-
ment
Percentage re-
covery after
treatment
Total amount
before treat-
ment
Total amount
after treat-
ment
Percentage re-
covery after
treatment
Silica
9.74
7.87
80.8
23.04
15.75
68.4
Soluble
ash
8.98
4.11
45.8
10.13
4.67
46.1
Calcium
0.37
0.50
135.0
0.52
0.66
127.0
Magne-
sium
0.24
0.23
96.0
0.47
0.46
98.0
Potas-
sium
2.08
0.46
22.1
4.52
1.18
26.1
Sodium
0.13
0.80
615.4
0.07
1.30
1,857.0
Phos-
phorus
0.17
0.08
47.0
0.22
0.11
50.0
Chlorine
0.017
nil
ml
0.306
0.008
2.6
The data show that the mineral constituents estimated were not uniformly
affected by the treatment. Thus the percentage of potassium, phosphorus
and chlorine were significantly lowered in the treated straws. The lowered
percentage of these minerals, when considered along with the loss sustained
in dry matter, show that during alkali treatment, considerable amounts of
these minerals were washed out of the straw. On the other hand, the per-
centages of calcium, magnesium and sodium were considerably increased in
the treated straws. These minerals were not apparently affected by the
alkali treatment. The total recovery of calcium, as shown in Table VI,
moreover, suggests that, during alkali treatment of the straws, some calcium
was deposited from an extraneous source. A later examination of the tap
water showed that it contained significant amounts of calcium which were
deposited on the straw during the course of treatment. The increase in the
sodium content of treated straws was obviously due to a certain amount of
the alkali having been absorbed in spite of the repeated washings.
(c) Since, after one treatment, the alkali is only partially exhausted,
it can be used again and thereby considerable economy can be effected. Ac-
cording to Godden [1920], by bringing the strength of the residual liquor
after each treatment up to its original strength, it may be made to serve for
several batches of straw. He calculated roughly that, for every 100 lb. of
treated straw 5 lb. of soda would be used up. In the present investigation,
the strength of the alkali in the mixed solution of residual liquor and the first
wash water was determined after the treatment of wheat and paddy straw.
The results obtained were as follows :—
1. The strength and composition of alkali solution before treatment :
(a) amount of NaOH
.
.
.
.
.
(b) amount of Na 2 CO 3
.
.
.
.
.
Total as Na 2 CO
.
.
.
.
.
18.90 gm.
1.40 gm.
26.44 gm.
270
The Nutritive Value of Alkali-treated Cereal Straws
2. The strength and composition of the residual liquor + first wash
water after alkali treatment of wheat straw :
(a) amount of NaOH . . . . .
(b) amount of Na 2 CO 3 . . . . .
Total as Na 2 CO 3 . . . .
0.09 gm.
17.20 gm.
17.32 gm.
From the above results, it may be observed that there was a small amount
of sodium carbonate present in the caustic soda solution originally used for
the treatment but, after treatment, the major portion of the recovered alkali
was present as sodium carbonate, which would indicate that the caustic soda
was extensively converted into sodium carbonate on exposure during the 20
to 24 hours soaking of the straw. When the alkali content in the ori-
ginal solution and the recovered liquor was calculated as sodium carbonate,
it was found that after one treatment of wheat straw, 65 per cent of the
alkali could be recovered. In a similar experiment with paddy straw, 63
per cent of the alkali used was recovered.
In order to test how effectively the recovered alkali could be used for
the next treatment, the following experiment was undertaken : To the
alkali solution recovered from the treatment of paddy straw, 10 gm. of solid
caustic soda were added. The added caustic soda was actually 50 per cent
of the alkali present in the solution used in the first treatment. A second
lot of 200 gm. of paddy straw was treated with the regenerated alkali solu-
tion. At the end of the treatment the alkali was recovered in the same way
as before and the recovered alkali was found to be about 66 per cent of its
original strength. By similar replenishment of the recovered alkali from the
second treatment, a third lot of straw was treated. The residual liquor
recovered after the third treatment was found to be very thick and viscid,
and, as its effectiveness was doubted, no further attempt to re-use the
alkali was made. The treated straws from the second and the third batch
were analysed to determine (a) the recovery of dry matter and (b) the per-
centage of crude fibre. The results have been set out in Table VII along
with similar figures obtained for the first lot.
TABLE VII
Composition of paddy straw after treatment with regenerated recovered alkali
solution
Per cent recovery of dry matter .
Per cent crude fibre (on dry basis) .
1st batch
74.8
46.10
2nd batch
76.0
45.52
3rd batch
76.5
45.00
It is apparent from the data given above that the quantitative change in the
composition brought about in the straw by the recovered and regenerated
alkali solution was practically similar to that of the first batch of straw treated
with the caustic soda solution. Moreover, the composition of the crude
fibre of the three lots of straw treated in the laboratory agrees well with that
of the paddy straw which had been treated on a large scale and with which
a feeding experiment had been actually carried out. The present
272
The Nutritive Value of Alkali-treated Cereal Straws
SECTION II.—The nutritive value of alkali-treated wheat straw
The experiment was so planned that the data yielded would not only
give the nutritive value of the treated straw but would also offer a comparative
picture as regards digestibility and metabolism when the animals were fed
with both untreated and treated straw from the same stack.
The experimental procedure was as follows :—
Four healthy Sahiwal heifers, over three and a half years of age were
selected for experiment. The live-weights of the animals were between 600
and 700 lb. All the animals were started on a ration containing untreated
wheat straw fed ad libitum and weighed quantity of rape cake with an allow-
ance of common salt of 1 oz. per head per day. The ration was fed for 10
days, at the end of which time harnesses were fixed on the animals with a view
to collecting their urine and faeces. The same ration was continued for
another 12 days and during the last 10 days, 24-hourly collections of
urine, faeces and food-residue were made. This period is called ' period 1 '.
At the end of this time the feeding of untreated straw was replaced by that of
treated straw but no other alterations were made in the diet. Following
the same procedure as in period 1, collections of samples were made towards
the end of period 2. The samples collected during the two periods were
subjected to chemical analyses with a view to determining the digestibility
co-efficient and the balance for nitrogen, calcium and phosphorus. Except
during the collection periods, the animals were weighed weekly.
Results
(a) Body weight.—The heifers in the present experiment were compar-
atively advanced in age ; nevertheless, a certain amount of growth was still
evident during the course of the investigation. In Table VIII is shown the
initial body weight (average of the weights taken on the three preceding weeks
before the experiment) and the average body weights in periods 1 and 2. It
is apparent from the data presented that the animals were gaining in weight
at a higher rate during period 2 than during period 1.
TABLE VIII
Body weight of the experimental animals
Animals
H 45
.
.
.
.
H
46
.
.
.
.
H 48 . . . .
H 51
.
.
.
.
Average for all animals .
Initial
weight
(lb.)
674
580
712
599
641
Average
weight in
period I
(lb.)
680
582
721
605
647
Gain in
weight in
period I
(lb.)
6
2
9
6
6
Average
weight in
period 2
(lb.)
701
592
738
620
663
Gain in
weight in
period 2
(lb.)
21
10
17
15
16