NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
STATISTICAL STUDY OF SPECIAL AND ORDINARY FED CALVES.
253
for special treatment were lighter in weight than those selected for ordinary
treatment, the special feeding has enabled them to attain weights which are signi-
ficantly more than those reached by ordinary fed calves at the end of the nine-
teenth week.
Table II gives the co-efficient of variation with its standard error, of the weekly
weights of the two groups. It will be seen that there is no significant difference in
the co-efficient of variation between the calves under the two treatments for differ-
ent weeks. This shows that there is no differenee in the variability in weight of the
calves under the two systems of feeding.
TABLE II.
Co-efficient of variation of weight for special and ordinary fed calves.
Age in weeks.
At birth
.
.
.
.
.
.
.
1 . . . . . . .
2 . . . . . . .
3 . . . . . . .
4 . . . . . . .
5 . . . . . . .
6 . . . . . . .
7 . . . . . . .
8 . . . . . . .
9 . . . . . . .
10 . . . . . . .
11 . . . . . . .
12 . . . . . . .
13 . . . . . . .
14 . . . . . . .
15 . . . . . . .
16 . . . . . . .
17 . . . . . . .
18 . . . . . . .
19 . . . . . . .
20 . . . . . . .
21 . . . . . . .
22 . . . . . . .
23 . . . . . . .
24 . . . . . . .
25 . . . . . . .
26 . . . . . . .
Ordinary.
12.13 ± 1.51
10.70 ± 1.33
10.34 ± 1.29
9.67 ± 1.20
9.07 ± 1.13
10.55 ± 1.31
10.15 ± 1.26
10.76 ± 1.34
10.80 ± 1.34
10.49 ± 1.31
11.89 ± 1.18
11.13 ± 1.39
10.21 ± 1.27
9.81 ± 1.22
9.38 ± 1.16
9.40 ± 1.17
8.78 ± 1.09
9.03 ± 1.12
8.95 ± 1.11
9.27 ± 1.15
9.80 ± 1.22
10.21 ± 1.27
6.76 ± 0.84
11.57 ± 1.44
12.33 ± 1.54
12.06 ± 1.51
12.64 ± 1.58
Special.
13.33 ± 1.75
13.46 ± 1.77
10.93 ± 1.43
11.69 ± 1.62
10.74 ± 1.40
11.26 ± 1.47
12.10 ± 1.58
12.35 ± 1.62
11.90 ± 1.66
12.58 ± 1.65
13.15 ± 1.73
12.63 ± 1.66
14.67 ± 1.93
12.82 ± 1.68
12.07 ± 1.58
12.13 ± 1.59
12.06 ± 1.58
11.81 ± 1.55
11.96 ± 1.57
11.30 ± 1.48
11.59 ± 1.52
11.36 ± 1.49
11.35 ± 1.48
11.46 ± 1.50
11.83 ± 1.55
11.45 ± 1.50
11.99 ± 1.57
The average percentage increase in weight of the calves, i.e., the ratio of the
increase in weight in any week to the weight at the end of the proceding week multi-
plied by 100, and its standard error as determined from the original data are given
in Table III.
254
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [V, III
TABLE III.
Average percentage increase in weight of calves.
Age in weeks.
1 . . . . . . .
2 . . . . . . .
3 . . . . . . .
4 . . . . . . .
5 . . . . . . .
6 . . . . . . .
7 . . . . . . .
8 . . . . . . .
9 . . . . . . .
10 . . . . . . .
11 . . . . . . .
12 . . . . . . .
13 . . . . . . .
14 . . . . . . .
15 . . . . . . .
16 . . . . . . .
17 . . . . . . .
18 . . . . . . .
19 . . . . . . .
20 . . . . . . .
21 . . . . . . .
22 . . . . . . .
23 . . . . . . .
24 . . . . . . .
25 . . . . . . .
26 . . . . . . .
Special fed calves.
5.93 ± 1.2959
12.61 ± 1.5122
10.70 ± 1.0764
8.30 ± 0.9152
7.50 ± 1.1605
7.61 ± 0.8416
7.63 ± 1.0218
9.71 ± 1.0640
7.07 ± 0.7857
5.99 ± 0.7137
8.40 ± 0.6656
6.91 ± 1.2526
7.40 ± 1.0847
6.75 ± 0.6598
6.88 ± 0.6986
6.29 ± 0.7239
6.91 ± 0.4944
4.68 ± 0.8097
6.35 ± 0.7543
5.54 ± 0.5865
4.64 ± 0.5774
5.27 ± 0.4287
4.44 ± 0.4685
4.30 ± 0.4903
4.34 ± 0.5058
3.76 ± 0.3171
Ordinary fed calves.
7.81 ± 0.9360
6.80 ± 1.1623
8.12 ± 1.2183
6.05 ± 0.9523
6.54 ± 0.9576
6.81 ± 0.9274
7.99 ± 0.9502
7.83 ± 0.6888
7.69 ± 0.7528
7.38 ± 0.6853
6.53 ± 0.7137
7.71 ± 0.5294
7.54 ± 0.5216
6.09 ± 0.6365
6.41 ± 0.5872
5.55 ± 0.5119
4.98 ± 0.5681
4.69 ± 0.4226
4.47 ± 0.5365
4.37 ± 0.4988
4.98 ± 0.4314
3.68 ± 0.4521
3.37 ± 0.3852
3.66 ± 0.3652
3.51 ± 0.4301
3.03 ± 0.4996
STATISTICAL STUDY OF SPECIAL AND ORDINARY FED CALVES.
255
A careful study of the above table reveals the following facts :—
(i) The variation as judged from the standard errors of the percentage
growth of both sets of calves is very high.
(ii) With the exception of a few weeks, viz., 2, 17, 19 and 22 where the special
fed calves grow at a decidedly more rapid rate, the increase in weight is almost
the same for both treatments. But, broadly speaking, we find that special
feeding has enabled the calves to grow at a more rapid rate during the period
under consideration. The cumulative effect of this is reflected in the body weight
at the end of six months when the special fed calves weigh 16 per cent. more than
the ordinary fed calves.
The correlation co-efficients between age and weight for special and ordi
nary fed calves are 0.9936 and 0.9966 respectively. This for all practical pur
poses may be taken as unity. In order to see the statistical significance between
the values of ' r ' for the calves under the two systems of treatment, the values
of z= ½ log 1+r / 1-r and the standard error of z, have been calculated and given
in the following table :
TABLE IV.
—
Special fed calves . .
Ordinary fed calves . .
Difference in z . . .
Sum of σ 2
. . .
z
r
0.9936
0.9966
..
..
z
2.8745
3.1877
0.3132
..
n—3
24
24
..
..
1/n-3 = σ 2
z
0.041666
0.041666
..
0.083332
The standard error of the difference in the values of z is equal to √0.08332
0.28867.
Therefore, the value of ' t ' for the difference in the values of ' z ' for special
and ordinary feeding is given by—
0.3132 / 0.2887 = 1.0849.
The theoretical value of ' t ' for 50 degrees of freedom at the five per cent.
level is equal to 2.008, which is greater than the calculated value showing that
there is no statistical significance in respect of correlation co-efficient between
ordinary and special feedings.
256
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [V, III
Since the correlation co-efficient between age and weight is nearly one for
calves both under special and ordinary treatments, it is evident that the age and
weight of calves under the two systems of treatments can be fairly represented by
means of straight lines.
Now let us proceed to determine the regression line of bulk weight on age.
The best line which approximately represents the weight of a calf (y) at any week
(x) is given by the general equation—
(y—y)=p/σx2 (x—x), where y is the mean of the values of y,
p= ε —xy, σ2 x=(x—x) 2 and i x is the mean of the values of x.
For ordinary fed calves,
y = 135.2222, p=436.5929, σ 2 x=60-6667 and x=0 (origin being the thirteenth
week).
Substituting and simplifying, we get the regression equation to be y—7.1966x
+135.2222.
Similarly y=143.1482, p=514.5185, σx 2 =60.6667 and x=0 for special
fed calves.
Substituting these values in the general equation, the regression equation
reduces to y=8.4811x+143.1482.
The above equations show that the average rates of growth for ordinary
and special fed calves are 7.1966 and 8.4811 pounds per week respectively.
In order to compare the rates of growth, first we must find the errors due
to random sampling in the values of the rates of growth determined from the
regression equations. The standard error of the regression co-efficient is given
by
, where S 2 is the mean of the sum of the squares of the
deviations from the linear regression having n—2 degrees of freedom, where n
has its usual meaning, and ε (x—x ) 2 is the sum of the squares of the deviations
of x from the mean value. (Fisher, page 126).
The sum of the squares of the deviations from the linear regression is equal to
[ε (x-x)(y-y)/[ε(x-x) 2 ].
where x and y are the means of the values of x and y (Fisher, page 234).
Using these formulæ, the standard error of the regression coefficient of weight
upon age for ordinary fed calves is equal to
STATISTICAL STUDY OF SPECIAL AND ORDINARY FED CALVES.
257
Similarly the standard error of the co-efficient of x for special fed calves
=
1508. 371/ 25/ √60. 6667×27
=0.1919
Since the standard errors of the rates of growth have been calculated, we
are in a position to see whether there is any statistical significance between the
rates of growth for ordinary and special fed calves.
Difference between the rates of growth=1.2845 lb. per week.
Standard error of difference = ±0.2245
Therefore, 't' =1.2845/0.2245=5.7216, which is greater than the theoretical value
2.008. (n=50)
Hence, the weight of the special fed calves increases at a significantly more rapid
rate than that of the calves under ordinary treatment.
An examination of Table I shows that the rate of growth of calves is not
constant, but it varies for different weeks. To get at a more approximate value
of the rate of growth, a parabolic curve is fitted to the data by using the method
of moments. Let the equation to the best parabola that fits the observed data
(that is, the weekly average weight in pounds corrected to the nearest whole
number) be y=ax 2 +bx+c. Equating the first three moments of the right
hand side to that of the left, we get three equations which enable us to determine
the values of a, b and c. Equating the moments we find that—
ε y=a ε x 2 +b ε x+27c . . . . . .
ε xy=a ε x 3 +b ε x 2 +c ε x . . . . . .
ε x 2 y=a ε x 4 +b ε x 8 +c ε x 2 . . . . . .
(i)
(ii)
(iii)
If the origin is taken as the thirteenth week, the values of ε x and ε x 3
are zero and the equations (i), (ii) and (iii) reduce to the simple form—
ε y=a ε x 2 +27c
ε xy=b ε x 2
ε x 2 y=a ε x 4 +c ε x 2
G
258
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [V, III
The values of ε y, ε xy, ε x 2 y, ε x 2 and ε x 4 for ordinary and special fed calves
have been tabulated below :—
TABLE V.
—
ε y . . . . . . .
ε x . . . . . . .
εx 2 yy . . . . . . .
ε x 2 . . . . . . .
εx 4 . . . . . . .
Ordinary fed
3651
11788
226716
1638
178542
Special fed
3865
13892
245104
1638
178542
Substituting these values in the equations above, we get the following two
sets of equation, one for ordinary and another for special fed calves :—
I.
and
II.
3651=1638a+27c
11788=16386
226716=178542a+1638c
3865=16384+27C
13892=1638B
245104=178542A+1638C
for ordinary fed calves.
for special fed calves.
We get the values of the unknowns by solving the two sets of equations
corresponding to the two parabolas.
The first set of equations gives—
a=0-06596, b=7.1966 and c=131.2207.
The second set gives—
A=0.1323, B=8.4811 and C=135.0046.
Hence, the parabolic curves for ordinary and special fed calves are—
y=0.06596x 2 +7.1966x+131.2207 and
y=0.1323x 2 +8.4811x+135.0046 respectively.
A perusal of the equations shows that as the co-efficient of x 2 for ordinary
fed calves is only about half as much as that of the special fed calves, the growth
is better represented by a parabola in the case of special fed calves. This can
be further established by calculating the sum of the squares of the deviations
of the observed values from the curvilinear regressions. The square of the devia
tion of any observed value from the graduated parabola is equal to (y—ax 2 —bx
—c) 2 . Therefore the sum of the squares=
ε y 2 +a 2 ε x 4 +b 2 ε x 2 + ε c 2 —2a ε x 2 y—2b ε xy—2c ε y+2ac ε x 2 ,
remembering that ε x 3 and ε x are zero. Substituting in the above equation
the values of ε y 2 , ε x 2 , ε x 4 etc. which have been already calculated and given
in Table V, we find that the sum of squares of the deviations from the parabolic
curves for ordinary and special fed calves to be 230.9260 and 81.7617 respec
tively, having 24 degrees of freedom. It is evident that the sum of squares of
the deviations is considerably less in the case of the special fed than that of the
ordinary fed calves. This statement has been further exemplified in graphs
1 and 2.
STATISTICAL STUDY OF SPECIAL AND ORDINARY FED CALVES.
259
Graph 1. Curves observed and fitted for ordinary fed calves up to 26 weeks.
G 2
260
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY.
[V, III
Graph 2. Curves observed and fitted for special fed calves up to 26 weeks.
STATISTICAL STUDY OF SPECIAL AND ORDINARY FED CALVES.
261
The equations dy/dx=0.1319&+7.1966 and dy/dx=0.2646x;+8.4811, which are
the first differential coefficients of the two parabolas given above, represent the
rates of growth of the calves under ordinary and special treatments at any ins-
tant. The difference in the rates of growth of the two groups at any age is given
by the expression 0.1327x+1.2845. Equating this expression to zero, it is seen
that the rates of growth of the calves under the two treatments are the same
during the fourth week. From the fifth week onwards the special fed calves
grow at a more rapid rate. Further, it is evident that difference in the rates
of growth steadily increases with age.
The justification for proceeding from the regression line to the regression
curve will be evident from the following considerations, where it has been shown
conclusively that there is considerable reduction in error by using a parabola
for representing the growth of calves under the two systems of treatment.
For ordinary fed calves the mean square of deviations S 1
2 and S 2
2 from
linear and curvi-linear regressions are 575.455/25=23.018 and 230.926/24=
9.622. Now, S 1
2 /S 2
2 =23.018/9.622=2.392.
Similarly, for special fed calves the mean square of deviations S/ 1 ' 2 and S/ 2 ' 2
from the linear and curvi-linear regressions are 1508.371/25=60.335 and 81.762/
24=3.407 S/ 1 ' 2 /S/ 2 ' 2 =60.335/3.407=17.709.
Theoretical values of S 1
2 /S 2
2 for n 1 =24 and n 2 =24 at 5 per cent. and 1 per
cent. levels of significance are 1.98 and 2.66, which proves that the parabola
is better for representing the weights of both sets of calves in this particular
case.
It may be pointed out that the general growth of live weights is represented
by curves of the form A— B — kt , where A, B, K are constants and t is the age
measured from maturity. An attempt was made to fit a logarithmic curve to
the data. But as the fit was not satisfactory, it was finally decided to use regres-
sion lines and curves for the comparison of the calves under the two treatments
during the period under consideration.
SUMMARY AND CONCLUSIONS
(1) It has been shown conclusively that the calves under special treatment are
able to put on significantly more weight than those under ordinary feeding.
During the interval of twenty-six weeks, the weight of special fed calves has in-
creased by about 16 per cent. over those under ordinary feeding.
(2) The equations dy/dx=0.1319x+7.1966 and dy/dx=0.2646x + 8.4811 which
represent the rates of growth of calves under ordinary and special treatments
show that calves under special feeding grow at a more rapid rate after the
fourth week. Besides, the average rates of growth as judged from the regression
equations are more in favour of special feeding than ordinary.
262
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [V, III
NOTE BY WYNNE SAYER.
I wish to make clear that in this paper nothing is claimed for special fed
calves except that as a result of special feeding they put on weight and grow more
rapidly.
As regards the main experiment on early maturity of which this work is a
part, data is still being collected on milk yields, constitution and the many other
factors which are to be considered in an investigation of this magnitude, and no
conclusions can yet be drawn on this aspect of the problem at such an early stage.
REFERENCES.
Fisher, R. A. (1932) Statistical Methods for Research Workers (fourth edition), Oliver
and Boyd, Edinburgh.
Sayer, W. (1934) Agriculture and Live-stock in India, 4, 633—644.
STATISTICAL STUDY OF SPECIAL AND ORDINARY FED CALVES.
263
APPENDIX.
TABLE I.
Scale of calf feeding—Special.
1
Age
1 week . . . . .
2 weeks
.
.
.
.
.
3
„
.
.
.
.
.
4 „ . . . . .
5
„
.
.
.
.
.
6
„
.
.
.
.
.
7
„
.
.
.
.
.
8 „ . . . . .
9
„
.
.
.
.
.
10
„
.
.
.
.
.
11 „ . . . . .
12
„
.
.
.
.
.
13
„
.
.
.
.
.
14
„
.
.
.
.
.
15
„
.
.
.
.
.
16 „ . . . . .
17
„
.
.
.
.
.
18
„
.
.
.
.
.
19
„
.
.
.
.
.
20 „ . . . . .
21
„
.
.
.
.
.
22
„
.
.
.
.
.
23
„
.
.
.
.
.
24 „ . . . . .
25
„
.
.
.
.
.
26
„
.
.
.
.
.
27
„
.
.
.
.
.
28
„
.
.
.
.
.
29
„
.
.
.
.
.
30
„
.
.
.
.
.
31 „ . . . . .
32
„
.
.
.
.
.
33
„
.
.
.
.
.
34
„
.
.
.
.
.
35
„
.
.
.
.
.
36
„
.
.
.
.
.
2
Milk
lb.
8
10
12
14
10
8
6
3
Skim-milk
lb.
..
..
..
..
2
4
6
4
Grain
lb.
..
..
1
1
1.5
2.0
3.0
5
Selt
oz.
..
..
1
1
1
1
1
264
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [V, III
TABLE I—concld.
1
Age
37 weeks . . . .
38 „ . . . .
39 „ . . . .
40 „ . . . .
41 „ . . . .
42 „ . . . .
43 „ . . . .
44 „ . . . .
45 „ . . . .
46 „ . . . .
47 „ . . . .
48 „ . . . .
2
Milk
lb.
4
2
..
3
Skim-milk
lb.
6
6
4
4
Grain
lb.
4.0
4.0
4.0
5
Salt
oz.
1
1
1
TABLE II.
Scale of calf feeding —Ordinary.
1
Age
1 week . . . .
2 weeks . . . .
3 „ . . . .
4 „ . . . .
5 „ . . . .
6 „ . . . .
7 „ . . . .
8 „ . . . .
9 „ . . . .
10 „ . . . .
2
Milk
lb.
8
8
10
10
12
12
12
12
8
8
3
Skim-milk
lb.
..
..
..
..
..
..
..
..
2
2
4
Grain
lb.
..
..
..
..
0.5
0.5
0.5
0.5
1.0
1.0
5
Salt
oz.
..
..
..
..
1
1
1
1
1
1
STATISTICAL STUDY OF SPECIAL AND ORDINARY FED CALVES.
265
TABLE II—concld.
1
Age
11 weeks . . . .
12 „ . . . .
13 „ . . . .
14 „ . . . .
15 „ . . . .
16 „ . . . .
17 „ . . . .
18 „ . . . .
19 „ . . . .
20 „ . . . .
21 „ . . . .
22 „ . . . .
23 „ . . . .
24 „ . . . .
2
Milk
lb.
6
6
4
4
4
4
2
2
2
2
..
..
..
..
3
Skim-milk
lb.
4
4
4
4
4
4
6
6
4
4
4
4
4
4
4
Grain
lb.
1.0
1.0
1.5
1.5
1.5
1.5
2.0
2.0
3.0
3.0
3.0
3.0
3.0
3.0
5
Salt
oz.
1
1
1
1
1
1
1
1
1
1
1
1
1
1
After 24 weeks, 2 pounds of concentrates only.
H
FURTHER OBSERVATIONS ON BOVINE NASAL
SCHISTOSOMIASIS.
BY
M. ANANT NARAYAN RAO, G.M.V.C.,
Lecturer in Parasitology, Madras Veterinary College
With Plates XXIII and XXIV and one text-fig.
(Received for publication on 4th June 1935.)
In his previous papers, the author has shown that the nasal schistosome
is different from S. spindalis Montgomery, 1906. A further study of the length-
frequency curves of their ova is of some interest.
Bovine nasal schistosomiasis exists in some animals without gross lesions
sufficient to attract the notice of a casual observer. In such animals the disease
can be recognised only after a close examination of the nasal mucous membrane
for small lesions, or for ova in the nasal washings under a microscope. The author
has often met with bovines and buffaloes suffering from nasal schistosomiasis with
no gross lesions. In the buffalo it is the exception rather than the rule for such
lesions to occur. Mr. A. Ramachandra Ayyar, District Veterinary Officer, Mada¬
napalle, stated in a communication that he has examined many buffaloes with
nasal schistosomiasis and none of them showed any gross lesions. In this paper
an attempt has been made to explain the cause of this " symptom-free " disease
in such animals.
LENGTH FREQUENCY CURVES OF OVA.
Fisher [1934] found a species of schistosome in the intestines of human beings
in Belgian Congo, which closely resembled S. haematobium and S. bovis morpholo-
gically, and he depended on biometry of the ova as a reliable species criterion
to differentiate the new parasite from the other two. To this end he measured
a large number of ova and plotted curves of their length frequencies. The curves
showed that the ova of the new schistosome occupied an intermediary position
between those of the other two and concluded that the parasite was a new species.
On this hypothesis, the present writer has portrayed the length frequency curves
of the ova of S. spindalis and S. nasalis with interesting results. (Text figure 1.)
( 266 )
FURTHER OBSERVATIONS ON BOVINE NASAL SCHISTOSOMIASIS
267
Length frequency curves of S. spindalis and S. nasalis.
The curves show that there is a marked difference in their maximum and minimum
lengths, which shows graphically that they are different species.
There is a striking resemblance between the curves as regards a deep notch
in the middle. It is possible that this is an indication of the probability that
these two schistosomes evolved from a common type but are now definitely
specialised with regard to their respective habits, etc, in their definitive hosts.
ABNORMALITY IN SHAPE OF THE OVA OF NASAL SCHISTOMES
In order to find out the abnormalities, if any, in the shape of the ova, the
writer and his assistant Mr. S. Vaidyanatha Mudaliar examined samples of nasal
washings obtained from the districts from over 895 bovines and 82 buffaloes, during
H 2
268
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY. [V, III
a period of one year ending with 31st January 1935. They were not able to find
any marked deviation from the typical shape of ova, excepting in their size. It
is therefore interesting to record that among the several thousands of mature
ova examined not even a single abnormal ovum conforming to the description
of any of the forms described by Datta [1932] and figured by Bhalerao [1933]
could be detected.
EXPRIMENTAL INFECTION.
At the end of the year 1933 it was decided to repeat the experimental in-
festation of nasal schistosomiasis to confirm the previous work of the writer [Rao,
1933, 1934]. To this end, Calf No. 516, which was under observation from Septem-
ber 1933, was first infested with S. spindalis cercariae and later with those of the
nasal schistosome.
In the third week of November 1933, the calf was infected with about 15,000
cercariae of S. spindalis through the nasal mucous membrane; in about eight
weeks it developed diarrhoea and dysentery for a few days and these symptoms
abated soon after without any treatment. The calf did not show lesions in the
nose or ova in the nasal washings, but its faeces contained plenty of ova of
S. spindalis during that period. The number of these ova in faeces gradually
lessened as the weeks passed by but they did not disappear altogether during the
period the calf was under observation. In the middle of February 1934, the calf
was infected with about 30,000 cercariae of the nasal schistosome by the nasal
route and on the 50th day after the event a very small number of ova was en-
countered in the nasal washings. For a time there appeared to be an appreciable
rise in the number of ova in the nasal discharge, and it lessened considerably
during the succeeding weeks. In any case they were not numerous at any time
during the whole period of one year the calf was under observation. The calf
was destroyed on 26th February 1935 and about 100 single males and 60 pairs of
nasal schistosomes were collected from the veins of the nasal mucous membrane,
and about 50 single males and 250 pairs of S. spindalis from the portal and mesen-
teric veins. The liver showed a well-marked periportal cirrhosis. This experiment
confirms the previous work of the writer [Rao, 1934]. In parenthesis it may
be mentioned that Mr. V. R. Phadke, Principal, Bombay Veterinary College, very
kindly informed the writer that he infected some calves with cercariae, presumably
of S. spindalis, with a view to producing nasal schistosomiasis. These calves
developed typical S. spindalis infection and the infestation was so heavy as to
produce acute diarrhoea and dysentery with the result that some of them died
and the others were treated with antimony tartrate to save them. None of
these, he said, developed nasal schistosomiasis, a fact which further supports the
findings of the author. In the annual report of the Bombay Veterinary College
for the year 1933-34, mention is made about these experiments.