NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
78 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ III, I
poor in nitrogen as well. Table VIII gives a comparative statement showing the
minerals present in the soil and the herbage.
TABLE VIII.
Mineral contents of soil and herbage.
—
CaO . . . .
P 2 O 5 Total . . .
K 2 O Total . . .
Nitrogen . . .
Paddock No. 3
Soil
Per cent.
0.14
0.05
0.23
0.042
Grass
Per cent.
0.528
0.396
1.172
0.801
Paddock No. 35
Soil
Per cent.
0.28
0.05
0.45
0.072
Grass
Per cent.
0.566
0.402
1.418
0.952
Paddock No. 32
Soil
Per cent.
0.28
0.04
0.31
0.074
Grass
Per cent.
0.556
0.420
1.245
0.801
Paddock No. 38
Soil
Per cent.
0.11
0.03
0.15
0.057
Grass
Per cent.
0.571
0.373
1.343
0.836
(NOTE.—The values for grass represent the means for whole period of eighteen months.)
There was apparently no correlation between the minerals in the soil and
herbage. The slight differences in the calcium content of the soils of the four
Paddocks do not show in the grass though Paddock No. 3 has a calcium content
which is half of that in Paddocks 35 and 32. The corresponding values for the
grasses in the three Paddocks vary only by 0.3 — 0.4 per cent. which is not
significant. The same applies to the phosphoric acid, nitrogen and potash contents.
Paddock 35 alone had a slightly higher nitrogen content in the herbage grown on it.
The only differences observed was that the variation during the course of the
experimental period was most marked in the case of protein in the herbage of
Paddock No. 38 when the minimum value was 1.78 per cent. while the maximum
value went up to 11.48 per cent., and Paddock No. 38 was rather poor in nitrogen.
The significance of this high range of variation is difficult to assess.
The response to manuring with nitrogenous fertilisers is the subject of an
investigation in progress.
THE NITROGEN—PHOSPHORIC ACID CORRELATION.
During the course of the investigation it was pointed out by the author [1930]
that there existed a parallelism between the nitrogen and phosphoric acid contents
of the herbage under investigation, and that the relationship pointed to the fact
that the nitrogen and phosphoric acid occurred together in combination. It was
also pointed out that the lack of correlation of P and Ca was indicative of there
being no combination of the two constituents, since they varied inversely through-
out the period. With this observation in view, the analytical results were subject
STUDIES IN SOUTH INDIAN PASTURES
79
to a statistical examination at the end of the investigation when sufficient material
had been collected. The correlation coefficients are given in Table IX below :—
TABLE IX.
Correlation coefficients for nitrogen-phosphate in the four sets of samples.
—
Value of r
Number of samples n
p for 0.1 when n= 18
Paddock 3
+0.312
18
0.378
Paddock 35
+0.0816
18
0.378
Paddock 32
+0.276
18
0.378
Paddock 38
+0.317
18
0.378
Mean values
of
4 Paddocks
+0.3196
18
0.378
The value of p is taken from Fisher [1925]. The coefficients were all positive but
not significant even for a 10 to 1 chance. The coefficients were all positive for the
whole set of 72 samples and were suggestive of a close connection between nitrogen
and phosphoric acid in the metabolic processes of the grass plant not only at one
stage of growth but throughout its life cycle.
The low values for the coefficient can only be explained by the fact that being
drawn during a long period they represented a heterogenous rather than a. homo-
genous series, on which a variety of climatic and other factors were operative.
Greenhill and Page [1931-2] obtained very highly significant correlation coeffi-
cients from " intensive pastures " and the one case of a non-significant correlation
was from a non-intensive pasture at Tollesby Farm. The conditions of growth at
the Livestock Research Station were non-intensive since no fertiliser treatment
had been attempted and this may also be one of the factors which might have
caused the lack of correlation between the nitrogen and phosphate. It has been
found in the course of other field and pot culture studies carried out in these
laboratories that statistical significance of results is not always obtainable. Tropi-
cal conditions with the diverse factors of climate, and differential plant growth
seem to influence results to a degree which can hardly be measured with mathe-
matical accuracy. Again nothing is known of the genetical factors operating in
causing variations in chemical composition no less than in structural and physical
characteristics. The grasses studied were all self sown and nothing is known about
the genetical relationship of the species. The positive nature of the correlation
coefficients obtained point to a relationship between nitrogen and phosphate, lack
of statistical significance notwithstanding.
The phosphate content of the isolated proteins may throw some light on the
significance of the correlation. To test whether the phosphate is associated with
80 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ III, I
the true protein a preliminary test was carried out and it was seen that the Stutzer
copper hydrate precipitate and the filtrate contained the following quantities of
nitrogen and phosphoric acid respectively.
—
Precipitate.........
Filtrate.........
Nitrogen
Per cent.
0.617
0.212
Phosphoric acid
Per cent.
0.400
0.012
The largest fraction of the phosphoric acid was associated with the precipitate
which represented the "albuminoid" moiety of the nitrogen, while the filtrate
which represented the " amide " moiety contained very small quantities. The
association of the phosphate with "protein", as is now understood, is admittedly
not proved by this preliminary estimation but points strongly in that direction.
Work in the direction of obtaining a more decisive proof is in progress.
MINERAL CONTENT OF THE HERBAGE IN RELATION TO ANIMAL NUTRITION.
The investigation, apart from the data provided for the seasonal variations,
throws light on the mineral content of the herbage of natural grasses, during their
life-cycle. Table X gives the range of variation of each of the important consti-
tuents during the two seasons.
TABLE X.
Range of variation of mineral matter in the herbage.
(Calculated on dry matter.)
—
Soluble ash . .
Calcium (CaO) . .
Phosphoric acid (P 2 O 5 ).
Potash (K 2 O)
. .
Protein . . .
Paddock 3
Maxi-
mum
per cent.
5.30
0.718
0.542
1.472
8.70
Mini-
mum
per cent.
2.76
0.378
0.284
0.901
2.98
Paddock 35
Maxi-
mum
per cent.
7.67
0.990
0.535
2.150
8.76
Mini-
mum
per cent.
2.67
0.280
0.282
0.870
2.94
Paddock 32
Maxi-
mum
per cent.
7.61
0.916
0.588
2.050
8.91
Mini-
mum
per cent.
2.70
0.255
0.243
0.701
2.98
Paddock 38
Maxi-
mum
per cent.
7.12
0.830
0.584
2.072
11.48
Mini-
mum
per cent.
1.82
0.234
0.235
0.568
1.78
STUDIES IN SOUTH INDIAN PASTURES
81
The calcium content during the dry season was high and reached a value which
was nearly equal to that of a good British pasture. During the wet season, how-
ever, which was the grazing season and during which time there was the most
herbage on the paddocks, the value fell and there seems to have been a shortage of
calcium. The phosphate content at no time equalled that of a good pasture and a
shortage of phosphorus is indicated throughout the period, the shortage was how-
ever most marked during the dry seasons when the values fell to the minimum.
Potash was similarly on the low side except during the period of flush and
before the grass came into flower. Excessive potash is, however, not a very desir-
able factor, in a tract where drinking water is scarce, owing to its diuretic effect.
Considered from the view-point of mineral deficiency there seems to be no actual
deficiency with the exception of calcium, during the best part of the grazing season
but a shortage of the other two minerals—phosphorus and potash—is indicated
almost throughout the year.
The question of the mineral requirements of livestock is still undecided., and
no definite standards have been formulated to meet the needs for the various classes.
In India the position is still more obscure owing to the utter lack of data bearing
on the subject. Crichton [ 1930 ] quoting from Henneberg places the requirements
of steers at about 100 grams CaO and 50 grams phosphoric acid per 1,000 lb. live-
weight. Hart and co-workers [ 1923 ] suggest a requirement of 6—8 grams of
CaO and phosphoric acid per lb. of milk produced as sufficient for maintenance and
production. Whether these standards will suit Indian cattle and conditions, re-
mains to be seen and work has been planned on these lines and will be carried out
in the near future. By analogy of the very low protein requirements as found to
be sufficient for maintenance and production in working bullocks in these labora-
tories (unpublished data), it is likely that the Indian animal can get on with a far
lower level of mineral intake.
It will be seen that with an intake of grass during grazing or soiling, of 50 lb.
the grass herbage having a moisture content of 60 per cent., an animal would be
getting about 50 grams and 36 grams of CaO, and 45 and 27 grams of phosphoric
acid during the best and worst periods, and this is the gross intake of which 15—
20 per cent. may be taken as percentage assimilated, the net amount would be
considerably below the standards suggested above. Theiler and Green [1932]
state that aphosphorosis is liable to occur when livestock are put on to pastures
having a phosphoric acid content of 0.21 per cent. and below and that 0.31 per
cent. is about the safe limit. According to this estimate aphosphorosis is not likely
to occur with livestock on the Hosur pastures, and actually no case has been
observed of suspected osteophagia or any pernicious appetite in the large herds
82 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ III, I
maintained at the Livestock Research Station. Van Zyl [ 1928 ] has noted that
native cattle in Africa are able to exist and reproduce normally on very poor
pastures and his observation seems to be confirmed in this country. The main diffi-
culty seems to be one of slow calcium and phosphorus starvation with a cumulative
effect over several generations perhaps, leading to debility and general poverty of
condition in locally bred stock. An experiment of a preliminary nature was con-
ducted by the author (unpublished data) in which it was shown that the feeding of
a mineral supplement containing bonemeal and lime was distinctly beneficial, its
action being prophylactic rather than curative in making for better conditions with
dairy young stock, the results will form the subject of a future communication.
That there is a mineral deficiency in some tracts of this Presidency is seen from
analysis in these laboratories of grasses collected in connection with a botanical
survey of fodder grasses some years ago. There are also some reports of osteopha-
gia and malnutrition and the subject will be taken up in detail at some future date.
The information regarding osteophagia is unauthenticated, and as far as is known,
no clinical evidence has been recorded of deficiency diseases due to low calcium and
phosphoric acid in fodders and feeds.
PRACTICAL SIGNIFICANCE OF THE RESULTS.
The practical significance of the results of this investigation can be summed up
as follows:—
(i) The best period for mowing for silage or hay-making is that when the
grass has flowered and before seeds have set. This practice would
conserve the maximum of protein and phosphoric acid. A sample of
hay made from the herbage of Paddock No. 32 contained 0.25 per cent.
phosphoric acid while the best value for the fresh herbage of the same
Paddock was 0.58 per cent. phosphoric acid, which meant that 50 per
cent. of the phosphoric acid was lost in the process of hay-making.
This loss is liable to occur in two ways, the first possible loss is the
lower nutritive value when the grass is dead ripe, the second being the
loss due to the removal of seeds by combing out as practised at the
Livestock Research Station, to remove the objectionable spears from
the hay. The coincidence of the period of best nitrogen and phos-
phoric acid content with that of the heaviest rainfall is unfortunate, and
long range forecasting has not reached a stage when the forecasts are
infallible. The rainfall of the North-east monsoon occurs in con-
nection with cyclonic storms traversing the Peninsula, and it is never
possible to forecast the exact track they follow, and warnings of
heavy rainfall cannot be issued with a definiteness that would help the
STUDIES IN SOUTH INDIAN PASTURES
83
farmer in the locality to start hay-making, hoping for no rain till his
stacks are up. The Livestock Research Station has, however, been
attempting to mow early and when the usual curing process has not
been possible to follow, artificial means have been adopted with some
measure of success. The other means of getting in the hay before the
dead ripe stage is to manure with ammonium sulphate and rush up
growth earlier than usual, this is being tried with some measure of
success with other species of grasses and may be a practical proposi-
tion if it means hay of higher nutritive value.
Making of silage from immature grass has been tried and is now the usual
practice at the Livestock Station, the resulting silage is of high
nutritive value and has none of the defects of that made from dead
ripe grass.
(ii) The feeding of a mineral supplement to young stock and cows while on
grazing is also indicated by the shortage or deficiency of calcium and
phosphoric acid. A supplement has already been recommended and is
in use for some time now.
(iii) Livestock improvement in this Presidency should have two main lines of
effort, one being the breeding side where better stock are bred by
careful selection or grading up existing herds, the other side of the
question and one of equal importance being to feed well for better
stock. The best animal may deteriorate by insufficient nutrition, and
malnutrition can undo the best efforts of the breeder. The results
reported on above point to a shortage of mineral nutrients and one
possible method of livestock improvement is that of feeding minerals
to keep up the quality of the cattle and thus ensure a healthy progeny.
SUMMARY.
(i) The problem of an adequate supply of fodder derived from the herbage
of natural grasses is acute in South India. The causes that have led to this
lack of natural pastures are two, namely, economic and climatic. The investigation
reported on is an attempt to solve the problem along the lines of a study of the
mineral content with a view to conserve the available supplies of herbage to the
best advantage.
(ii) At the Livestock Research Station, Hosur, where the study was carried out,
the pasture was one of almost pure culture Spear grass (Andropogon contorlus) and
the results show that the minerals and nitrogen of the grass have variations depend-
ing on the season and period of growth. The variations are very similar to those
recorded in other countries. The main factor involved seems to be one of the
G
84 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ III, I
period of growth rather than the actual time of the year or incidence of rainfall.
Nitrogen and phosphoric acid curves followed a parallel course, while the calcium
curve varied inversely as the nitrogen and phosphoric acid. There was a positive
but statistically not significant correlation between nitrogen and phosphoric acid, the
positive correlation pointing to an intimate constitutional relationship between the
two.
(iii) The pastures apparently had a shortage of calcium and phosphoric acid at
almost all parts of the year. An adult working animal would thus get just suffi-
cient of the two nutrients for maintenance, while the young animal and the milch
cow are both in danger of suffering from a deficiency if grazing on pastures without
any concentrate. A mineral supplement is thus indicated for use for this class of
animals as a prophylactic.
(iv) The mowing of the herbage for hay should be done early if the best is to
be got out of the grass since once seed is set the values for phosphoric acid and
nitrogen fall rapidly and the hay is of poor nutritive value as compared with the
herbage at the best period of growth. Silage-making is possible and is being done
at the period of good nutritive value.
The work was carried out at the Coimbatore Agricultural Research Institute
and the Livestock Research Station, Hosur, and my best thanks are due to the
Government Agricultural Chemist, the Deputy Director of Agriculture, Livestock,
and the Superintendent, Livestock Research Station, for the facilities placed at my
disposal and to Mr. Purushottam Charlu, B.A., for help in connection with the
statistical examination of the data.
REFERENCES.
Aston, B. C. (1931). New Zealand, Jour. Sc. and Tech, 12, 304.
Crichton, J. (1930). Jour. Diary Research, 2, 21.
Cruickshank, E. M. (1926). Jour. Agri. Sc., 16, 89.
Fergusson, W. S, (1931). ibid. 21. 233.
Fisher, R. A. (1925). Statistical Methods for Research Workers, Edinburgh and London, 174
Greenhill, A. W, and Page, H. J. (1931). Jour. Agric. Sc., 21, 220.
Hart and co-workers (1923). Jour. Biol. Chem.
Orr, J. B. (1929). Minerals in Pastures, London.
Orr, J. B., and Holm, A. (1930). Sixth Report of the Economic Advisory Committee on the
mineral content of natural pastures, London.
Ramiah, P. V. (1930). Annual Report to the Director of Agriculture, Madras.
Royal Commission on Agriculture in India (1928, 1). Report.
Royal Commission on Agriculture in India (1928, 2). Report, 178.
Theiler, A., and Green (1932). Nutrition Abstracts and Reviews, 1, 359.
Van Zyl (1928). 13th and 14th Reports of the Director of Veterinary, Education and Research,
Union of South Africa. 985—1036.
Woodman and co-workers (1926). Jour, Agric Sc., 16, 205.
THE CURATIVE TREATMENT OF SURRA (TRYPANOSOMA
EVANSI INFECTION) IN EQUINES BY MEANS OF
" BAYER 205 " (NAGANOL)
BY
S. K. SEN, M.Sc., F.E.S.,
Assistant Research Officer, Imperial Institute of Veterinary Research, Muktesar.
(Received for publication on 9th June 1932.)
During the decade that has elapsed since the introduction of " Bayer 205 "
in the field of medical and veterinary science, fairly extensive trials have been
carried out with this drug in combating infections due to practically all species of
trypanosomes known to be pathogenic to man and animals, and except in infections
due to the congolense group of trypanosomes, the results obtained from the
use of this drug may be declared to have been uniformly satisfactory. In the
case of equine surra in particular, " Bayer 205 " has yielded results that have
rightly caused it to be acclaimed as a drug possessing very superior trypanocidal
properties, and at the present moment it is the drug of choice in the treatment
of this disease.
However, cases of equine surra are now and then encountered which are
markedly resistant to the action of this drug, and observations at Muktesar showed
that in a number of such cases the ineffectiveness of the drug might be ascribed
to the fact that such of the parasites as had found their way into the cerebrospinal
system remained unaffected by the drug present in the general circulation. On
the other hand, some cases were also observed where intravenous medication
alone without simultaneous intrathecal treatment " was capable of producing
at any rate apparent recovery for a considerable period, even in equines that had
undoubtedly harboured infection in the cerebrospinal canal" [Edwards, 1928].
It seemed, however, to be a desirable procedure, in the treatment of equine surra,
to sterilize separately, by the simultaneous injections of the drug, both the general
circulation and the cerebrospinal canal, particularly in view of the fact that it is the
latter locality from where relapse strains are generally held to originate. The
combined intravenous intrathecal method of treating equine surra with "Bayer
205 ", as at present recommended by this Institute, is based upon the principles
mentioned above, but this method is hardly necessary for adoption for prophylactic
purposes or in early stages of the disease where cerebrospinal involvement is not
( 85 )
G2
86 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [ III, I
likely to have occurred. In practice, however, it is not always an easy matter
to come to a decision as to whether the disease has progressed to a stage where
intrathecal medication is called for, and this is particularly so when, as is usually
the case, the subject under treatment does not bear any definite history as to the
date when infection might have been contracted, whilst the examination of the
cerebrospinal fluid—which is the only known method for making sure as to the
presence of parasites in that tract—involves operations which it is hardly possible
to carry out under the conditions obtaining in the field. It would therefore
seem to be a good plan to apply the combined method of treatment to all cases
irrespective of the fact whether such a procedure is warranted by the degree of
infection or not.
The problem of combating equine surra would thus have been finally solved,
were it not for the fact that the technicalities of the method and the prolonged
nature of the treatment (for the full course of treatment entails three injections
at fortnightly intervals) have led more than one field worker in India to apply
to this Institute for advice as to whether the treatment cannot be carried out
by methods simpler than the one recommended at present. The difficulties
of the combined method, as experienced by the field worker, are illustrated by the
following remarks reproduced from a communication recently addressed to this
Institute by an Army Veterinary Officer in India :—
" It is considered almost essential for an operator performing the intrathecal
operation to have one or two reliable men to control movement of the horse's head
which is occasionally responsible for fatalities and in many cases loss of part of the
intrathecal dose, which is very undesirable. The operator may supervise casting
operations and correct flexing of the head into the chest to stretch the atlanto-
occipital ligament, but he certainly cannot do much supervision apart from his
own job, once the needle is nearing the spinal canal. The heavy manual labour
of ' tying up' several animals in succession tends also to make the hand of the
operator unsteady. Therefore the assistance of two or three men familiar with the
work is considered indispensable."
The difficulty of the combined intravenous-intrathecal method would thus
appear to be twofold : one may be described as qualitative, being inherent in the
nature of the operation itself, and the other may be regarded as quantitative,
in view of the multiple injections entailed by the method. The two questions
that call for attention relate therefore to the relative efficacy of the intravenous
and the intravenous-intrathecal method of treatment (using " Bayer 205 " alone or in
combination with other drugs) and also to whether the period of treatment may
not be substantially shortened by reducing the number of injections to one or,
at the most, two, with as short an interval between them as possible. In the