NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
120
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [VII,
II
TABLE VI
The influence of season of kidding on service period
Frequency distribution of service periods of lactations comencing in the different months of the year
Service period
in days Class
mid-point
10
30
50
70
90
110
130
150
170
190
210
230
250
270
290
310
330
350
370
390
410
430
450
470
Total .
Mean
service
period—days.
January
..
..
5
1
2
2
1
3
2
..
..
1
..
..
2
1
..
..
..
..
..
..
..
..
20
138
February
..
1
..
3
2
3
6
2
2
..
2
..
..
1
..
..
..
..
..
..
..
..
..
1
24
152.5
March
..
..
..
..
..
2
4
2
5
..
1
..
1
..
..
..
..
..
..
..
..
..
..
..
16
165
April
..
2
2
3
1
2
..
2
..
..
1
1
1
1
..
..
..
..
..
..
..
..
..
..
16
121.25
May
..
..
..
3
2
1
2
..
1
..
..
..
..
..
..
..
..
..
..
..
..
2
..
..
11
162.7
June
..
4
4
4
4
1
..
..
2
..
..
..
1
..
1
..
..
..
..
..
..
..
..
..
21
92.9
July
1
2
1
..
..
1
1
..
..
..
..
1
..
..
..
..
..
..
..
..
..
..
..
..
7
84.3
August
..
6
5
2
2
..
2
6
1
2
..
1
1
..
..
1
..
..
..
..
..
..
..
..
29
112.1
September
..
1
4
3
..
1
..
1
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
10
70
October
2
4
5
1
6
..
2
2
1
3
1
..
1
1
..
..
..
..
..
..
..
..
..
..
29
104.5
November
..
..
1
2
2
2
2
5
2
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
19
140.5
December
2
1
..
2
..
6
3
4
3
4
..
3
1
1
1
..
..
1
..
..
..
..
..
..
32
155
Total
5
21
27
24
21
21
23
27
19
9
6
7
7
5
5
2
1
1
..
..
..
2
..
1
234
127.94
INFLUENCE OF ACCESSORY FACTORS ON MILK BY INDIAN GOATS
121
TABLE VII
Influence of season of kidding.
Month of kidding
January . . . .
February . . . .
March . . . .
April . . . .
May . . . .
June . . . .
July . . . .
August . . . .
September . . . .
October . . . .
November . . . .
December . . . .
Total .
No. of
lactations
averaged
20
24
16
16
11
21
7
29
10
29
19
32
234
Average
lactation
yield
425
425
428.1
428.1
379.5
351.2
360.7
468.1
280.0
312.9
425.0
446.9
403
Average
days in
milk
188
170
172.5
151.25
137.3
118.4
124.3
140.4
132.0
131.4
167.9
170
152.64
Average
service
period
138
152.5
165
121.25
162.7
92.9
84.3
112.1
70.0
104.5
140.5
155
127.94
Average
daily
yield
from
kidding
to
kidding
1.647
1.407
1.358
1.579
1.214
1.444
1.543
1.786
1.273
1.227
1.461
1.466
1.45
It will be seen from these that kiddings are not distributed over the various
months in any regular order, except that in the months of May, July and
September they are less frequent. Greatest frequency, however, occurs during
the season October to February, showing that the period May to September is
more favourable for conception than the remaining period of the year. The
larger frequencies in June and August cannot be explained properly ; but for
these two irregularities the goats may generally be said to be prone to freshening
during the winter months.
With the exception of an irregularity in August, the average lactation yields
are generally above the average of the herd for November to April and below the
average during the remaining six months. But the average lactation lengths
and service periods follow the same trend. The goats kidding in May to October
conceive quicker than others and consequently go dry sooner. This necessarily
makes the lactation lengths shorter and the average lactation yields lower. (The
influence of lactation length and service period on lactation yield is examined
in a later section). But a lower lactation yield does not mean lower economic
efficiency. That animal is economically most efficient which yields the largest
quantity of milk during a given period of time, and when lactations are studied
the economic worth is best measured by the average daily yield during each
122
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [VII, II
kidding interval. These averages are given in the last column of Table VII.
They do not afford any definite indication that kidding in a particular season
would enhance the economic value of the animal. On the other hand it would
be advantageous, in the interests of a level supply of milk, to have the matings
controlled, as far as possible, in such a way that kiddings are evenly distributed
in the different months of the year.
Seeing that lactation yields vary according to the season of kidding, it is
necessary, in judging animals by their lactation yields, to have a measure of the
variation. Figures in Table VIII are worked out with this object in view. These
figures indicate what percentage should be added to or subtracted from lacta-
tion yields of goats kidding in the various months of the year so as to reduce
them to the average for the whole year.
TABLE VIII.
Correction for month of kidding
Month of kidding
January . . . . . . . . . . .
February . . . . . . . . . . .
March . . . . . . . . . . .
April . . . . . . . . . . .
May . . . . . . . . . . .
June . . . . . . . . . . .
July . . . . . . . . . . .
August . . . . . . . . . . .
September . . . . . . . . . . .
October . . . . . . . . . . .
November . . . . . . . . . . .
December . . . . . . . . . . .
Correction
per cent
—5.18
—5.18
—5.87
—5.87
+ 6.1
+14.7
+11.7
—13.91
+43.9
+28.7
—5.18
—9.84
The paucity of numbers in the different months limits the value of these
corrections. With the exception, however, of September and October kidders,
the correction is not of considerable magnitude.
* See footnote to Table XII.
INFLUENCE OF ACCESSORY FACTORS ON MILK BY INDIAN GOATS
123
TABLE IX
Correlation between lactation yield and service period
Days—service period. Class mid-point.
Lactation yield. Class
mid-point
5
125
175
225
275
325
375
425
475
525
575
625
675
725
775
825
875
925
975
1,025
Total
.
10
..
1
2
1
..
1
..
..
..
..
..
..
..
..
..
..
..
..
..
..
5
30
1
..
3
4
5
5
1
1
..
1
..
..
..
..
..
..
..
..
..
..
21
50
..
1
2
5
4
2
7
3
2
1
..
..
..
..
..
..
..
..
..
..
27
70
..
..
1
1
3
6
4
3
1
2
..
1
..
..
2
..
..
..
..
..
24
90
..
2
..
2
2
3
3
4
3
1
..
..
..
..
..
1
..
..
..
..
21
110
..
..
..
..
3
..
6
2
3
2
..
4
..
..
..
..
..
..
..
1
21
130
..
..
2
1
4
1
1
2
5
..
4
..
1
1
..
1
..
..
..
..
23
150
..
1
1
..
1
6
2
1
5
2
1
3
..
..
1
2
1
..
..
..
27
170
..
1
..
2
1
1
4
3
3
2
1
1
..
..
..
..
..
..
..
..
19
190
..
..
1
2
..
..
1
1
1
..
..
1
..
1
1
..
..
..
..
..
9
210
..
..
..
..
..
1
2
..
..
..
..
1
1
..
1
..
..
..
..
..
6
230
..
..
..
..
1
1
..
..
2
..
1
..
1
..
1
..
..
..
..
..
7
250
..
1
1
1
..
..
2
..
2
..
..
..
..
..
..
..
..
..
..
..
7
270
..
1
..
1
..
..
1
..
..
..
..
..
..
..
..
..
..
..
..
..
5
290
..
..
..
..
..
2
1
..
..
..
..
1
..
..
..
1
..
..
..
..
5
310
..
..
..
..
..
..
..
..
..
..
..
..
..
2
..
..
..
..
..
..
2
330
..
..
1
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
1
350
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
370
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
390
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
410
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
430
..
..
..
..
4
1
..
..
..
..
..
..
1
..
..
..
..
..
..
..
2
450
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
470
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
1
Total
1
8
14
20
24
30
35
21
29
12
7
12
4
4
6
5
1
..
..
1
234
Mean service period
.
.
.
.
.
.
Mean lactation yield . . . . . .
127.94 days.
403
lbs.
Standard deviation of service period . .
Standard deviation of lactation yield
Coefficient of correlation .
81.38 days.
171.4 lbs.
0.2658.
124
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [VII, II
INFLUENCE OF SERVICE PERIOD
Table IX shows the correlation between service period and lactation yield.
The coefficient of correlation is as low as 0.2658 which would seem to indicate
that service period has little or no influence on the yield of milk in a lactation.
This is contrary to experience. The explanation lies in the fact that the duration
of the milking period is dependent not only on pregnancy but on other factors
as well—goats seem to go dry early in lactation even though they do not happen
to be pregnant. This will be clear from Table X.
It is seen from this table that in quite an appreciable number of cases the
service period exceeds the lactation length, showing that at least in these cases
it is not the advance of pregnancy that is responsible for the cessation of lactation.
The coefficient of correlation between lactation length and service period is only
0.4037. This confirms the fact that pregnancy is not the sole factor that deter-
mines the length of milking period. From the records it is not possible to find
out which of the animals have gone dry owing to the advance of pregnancy and
which for other reasons. The other factors that conceivably influence the length
of milking period may be sickness, the plane of nutrition, etc. This requires
a separate investigation. The length of lactation has a marked effect on the
lactation yield. This will be seen from Table XI.
INFLUENCE OF ACCESSORY FACTORS ON MILK BY INDIAN GOATS
125
TABLE X
Correlation betioeen lactation length and service period
Class mid-point. Service period—days
Lactation length in days
Class mid-point
70
90
110
130
150
170
190
210
230
250
270
290
Total .
10
1
3
1
..
..
..
..
..
..
..
..
..
5
30
2
7
9
2
1
..
..
..
..
..
..
..
21
50
..
3
15
7
2
..
..
..
..
..
..
..
27
70
..
3
3
9
7
2
..
..
..
..
..
..
24
90
..
1
3
2
5
6
3
..
..
..
..
..
21
110
..
..
1
1
4
9
6
..
..
..
..
..
21
130
..
1
6
3
1
..
7
5
1
..
..
..
23
150
..
1
2
1
1
2
5
8
4
3
..
..
27
170
..
1
5
1
1
1
2
4
3
1
..
..
19
190
..
1
2
1
..
2
..
..
2
1
..
..
9
210
..
..
..
..
..
2
..
..
..
2
2
..
6
230
..
..
..
1
1
..
2
1
..
..
..
2
7
250
2
1
2
..
1
..
1
..
..
..
..
..
7
270
..
1
2
..
..
1
1
..
..
..
..
..
5
290
..
..
..
1
..
1
..
1
..
..
..
1
5
310
..
..
..
..
..
..
1
..
..
..
1
..
2
330
..
1
..
..
..
..
..
..
..
..
..
..
1
350
..
..
..
..
..
..
1
..
..
..
..
..
1
370
..
..
..
..
..
..
..
..
..
..
..
..
..
390
..
..
..
..
..
..
..
..
..
..
..
..
..
410
..
..
..
..
..
..
..
..
..
..
..
..
..
430
..
..
..
..
1
1
..
..
..
..
..
..
2
450
..
..
..
..
..
..
..
..
..
..
..
..
..
470
..
..
..
..
1
..
..
..
..
..
..
..
1
Total
6
24
50
29
27
27
29
19
10
7
3
3
234
Mean lactation length . . . . . .
Standard deviation of lactation length . . .
152.64 days.
50.64 days.
Mean service period .. ..
Standard deviation of service period .
127.94 days
81.38 days
Coefficient of correlation
.
.
0.4037.
126
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [VII, II
TABLE XI
Correlation between lactation yield and lactation length
Days in milk
Yield
75
125
175
225
275
325
375
425
475
525
575
625
675
725
775
825
875
925
975
1,025
Total .
Mean of columns .
70
..
2
3
1
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
..
6
166.7
90
1
4
6
2
4
3
3
1
..
..
..
..
..
..
..
..
..
..
..
..
24
237.5
110
..
2
5
13
11
6
7
3
3
..
..
..
..
..
..
..
..
..
..
..
50
287.0
130
..
..
..
2
2
7
6
2
3
4
..
..
1
..
1
1
..
..
..
..
29
419.8
150
..
..
..
2
3
5
8
4
2
1
..
1
..
..
1
..
..
..
..
..
27
388.0
170
..
..
..
..
2
3
5
4
5
1
..
4
1
..
2
..
..
..
..
..
27
471.3
190
..
..
..
..
1
4
3
4
7
2
3
1
1
2
..
..
..
..
1
29
492.24
210
..
..
..
..
1
..
3
1
6
2
3
1
..
..
2
..
..
..
..
19
511.8
230
..
..
..
..
..
..
..
2
3
2
..
1
..
..
1
1
..
..
..
10
565.0
250
..
..
..
..
..
1
..
..
..
..
..
3
1
1
..
1
..
..
..
..
7
632.1
270
..
..
..
..
..
..
..
..
..
..
..
..
..
1
1
..
..
..
..
..
3
608.3
290
..
..
..
..
..
..
..
..
..
..
1
1
..
..
1
..
..
..
..
..
3
658.3
Total
1
8
14
20
24
30
35
21
29
12
7
12
4
4
6
5
1
..
..
1
234
..
Mean yield
.
.
.
.
.
Standard deviation of yield . . .
403 Ibs.
171.4
lbs.
Mean days in milk . . . .
Standard deviation of days in milk .
152.64 days
50.64 days
Coefficient of correlation
0 . 6448.
INFLUENCE OF ACCESSORY FACTORS ON MILK BY INDIAN GOATS
127
FIG. 6. Relation of lactation yield to lactation length.
The coefficient of correlation is 0.6448. Figure 6 shows the increase in milk
yield corresponding to an increase in the length of lactation. It will be seen
that the curve cuts through the data fairly well. The regression equation shows
that on an average the yield of milk in a lactation increases at the rate of 2.18 lbs.
per day increase in the length of lactation. The equation obtained is—
Y=2.18x+70.24
where Y is the lactation yield in lb. and x the length of milking period in days.
There is a fundamental fallacy in assuming a linear relation between the two, for
this would show that the yield goes on increasing indefinitely as the lactation
is prolonged and that there would be some yield even if the animal does not re-
main in milk for a single day. But ordinarily such extremes are not met with
and corrections based on this equation can be applied within easonable limits
of lactation lengths that are found in practice. A better method of obtaining
figures of correction would be from the lactation curve based on the knowledge of
persistency. But as this is not available the following are given tentatively.
H
128
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [VII, II
TABLE XII
Correction for lactation length*
Lactation length in days
60—79 . . . . . . . .
80—99 . . . . . . . .
100—119 . . . . . . . .
120—129 . . . . . . . .
140—159 . . . . . . . .
160—179 . . . . . . . .
180—199 . . . . . . . .
200—219 . . . . . . . .
220—239 . . . . . . . .
240—259 . . . . . . . .
260—279 . . . . . . . .
280—299 . . . . . . . .
Percentage to be
added to or sub-
tracted from lacta-
tion yield to obtain
yield for 150 days
78
49
28
12
..
—10
—18
—25
—31
—35
—40
—43
The influence of age and dry period is not examined. As the majority of the
goats studied are first kidders no preceding dry periods are available in their
case ; and until they have remained in the farm for some years sufficient data
are not available for studying the influence of age.
* These corrections are based upon raw lactations and not on those once corrected
for season of kidding. The working out of accurate corrections for the elimination of the
influence of various factors is a complicated matter and should be done by the method
of partial correlations. But as this is only a preliminary study and as sufficient material
is not available for studying all the factors it is not thought necessary to go into greater
detail at this stage. What is intended now is only a very rough indication of the ap¬
proximate amount of variation caused by individual factors.
When corrections for length of lactation are applied, corrections for season may
be ignored ; for we have already seen (vide Table VIII) that (1) except for September
and October kidders influence of season is not considerable and (2) part of the influence
of season is due to difference in lengths of lactation.
INFLUENCE OF ACCESSORY FACTORS ON MILK BY INDIAN GOATS
129
FIG. 7. Relation between average kidding interval
and average yield.
OPTIMUM KIDDING INTERVAL
Sufficient material is not available for examining the more important ques-
tion of optimum length of kidding interval. Rejecting those which have not
remained in the herd for at least three lactations we are left with only thirty-five
goats. Their average kidding intervals, lactation lengths, daily yield during life-
time, etc., are presented in Table XIII. Two indices are adopted for measuring
the economic worth—one is the standardised lactation yield (Standardised to a
normal length of 150 days by making use of corrections given in Table XII)
and the other the average daily yield during life-time. The kidding intervals are
classified into six to seven months, seven to eight months, etc., and averages
during these intervals are worked out. These are represented graphically in Fig.
7, the yields being plotted against the mid-point of the intervals represented
on the X-axis. It will be seen that the standardised lactation yield as well as
the average daily yield during life-time increases gradually with increase in the
length of kidding interval, reaches a maximum when the kidding interval is 255
days (i.e., 8 to 9 months) and then falls to a minimum at 315 days. The yield
again rises, but the data beyond the interval of 315 days are unreliable as the
population on which the average is based, is only one in one case and two in the
other case. This leads one to the conclusion, that the maximum return is obtain-
ed out of a goat when she is made to kid once every eight or nine months, i.e.,
by serving her between three and four months after freshening.
130
THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [VII, II
TABLE XIII
Average lactation yield and average kidding interval during life time
No.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
No. of
lactations
averaged
1
3
4
3
3
5
3
5
4
4
4
3
4
4
3
Total
yield of
milk
during
life-time
2
1,473
2,198
886
1,603
2,616
804
1,806
2,182
2,033
2,372
892
1,166
742
1,284
Total
days in
milk (a)
3
546
637
338
561
840
464
532
671
553
727
327
497
456
468
Total
days
dry (b)
4
605
784
347
303
407
348
588
494
560
747
435
303
317
301
Total
kidding
interval
(a + b)
5
1,151
1,421
685
864
1,247
812
1,120
1,165
1,113
1,474
762
800
773
769
Average
lactation
yield
during
life-
time
6
491
550
295
534
523
268
361
546
508
593
297
291
186
428
Average
kidding
interval
during
life-
time
7
384
355
228
288
249
271
224
291
278
369
254
200
193
256
Average
lacta-
tion
length
8
182
159
113
187
168
155
106
168
138
182
109
124
114
156
Average
day
period
9
202
196
116
101
81
116
118
124
140
187
145
76
79
100
Average
daily
yield
during
life-
time
10
1.28
1.55
1.29
1.85
2.10
.99
1.61
1.88
1.83
1.61
1.17
1.46
.96
1.67
INFLUENCE OF ACCESSORY FACTORS ON MILK BY INDIAN GOATS
131
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
5
4
5
5
5
4
4
3
5
4
4
3
3
3
3
3
3
4
3
3
5
1,729
1,716
2,422
1,512
1,628
2,176
1,542
1,002
1,442
1,591
2,663
1,695
914
1,044
1,118
1,121
1,082
1,043
1,614
1,420
1,880
693
789
715
585
734
870
527
400
778
512
604
556
451
423
468
509
439
460
485
485
877
849
473
518
719
467
297
474
323
576
503
392
184
362
343
366
315
239
300
247
219
486
1,542
1,262
1,233
1,304
1,201
1,167
1,001
723
1,354
1,015
996
740
813
766
834
824
678
760
732
704
1,376
345.8
429
484
302
326
544
385.5
334
288
398
666
565
305
348
373
374
361
261
538
473
376
308
316
247
261
240
292
250
241
271
254
249
247
271
255
278
275
226
190
244
235
273
139
197
143
117
147
218
132
133
156
128
151
185
150
141
156
170
146
115
162
162
175
170
118
104
144
93
74
119
108
115
126
98
61
121
114
122
105
80
75
82
73
97
1.12
1.36
1.96
1.16
1.36
1.86
1.54
1.39
1.06
1.57
2.68
2.29
1.13
1.37
1.35
1.36
1.60
1.37
2.21
2.01
1.38
132 THE INDIAN JOURNAL OF VETERINARY SCIENCE AND ANIMAL HUSBANDRY [VII, II
SUMMARY
Data are presented showing the influence of season of kidding and length
of lactation on lactation yields of goats ; and corrections are worked out for
eliminating the effect of these factors. It is found that excepting in the case of
September and October kidders the corrections in respect of season are not of
considerable magnitude. Length of lactation has an appreciable effect on the
magnitude of the lactation yield.
Goats are found to go dry very often for reasons other than pregnancy. The
influence of service period could not, therefore, be ascertained.
Sufficient data are not available for studying the influence of age and dry
period.
The limited material available goes to show that the optimum kidding in-
terval for goats is eight to nine months, which corresponds to a service period of
three to four months.
The volume of data being very limited, the conclusions drawn are only tenta-
tive.
REFERENCES
Sanders, H. G. J. Agric. Sc. 17, 339, 502 ; 18, 46, 209.
—————
J. Agric. Sc. 17, 21.
—————
J. Agric. Sc. 20, pt. 2.
SELECTED ARTICLE
RECENT DEVELOPMENTS IN THE CHEMISTRY OF
VITAMINS*
BY
B. B. DEY, M.Sc., D.Sc., F.I.C.
Professor of Chemistry, Presidency College, Madras and Honorary Reader in Chemistry
to the University of Madras
[Reprinted from The Indian Medical Journal, Vol. 31, No. 1, January 1937]
GENERAL OBSERVATIONS
THE subject of vitamins is now a very common one. Even a non-scientific
man knows about it. These vitamins at one time were considered to be some-
thing abstract, whose actual chemical entity was very doubtful and I think I
can say that many well-known men of science used to be rather sceptical about
the real existence of vitamins. Our requirements are complex. Mere food with,
nitrogenous substances like protein, etc., will not supply enough to keep us func-
tioning normally. We must have certain things more which we call accessory
factors. The so-called accessory food factors which have not been heard of by
the preceding generation and which were regarded 25 years ago by men even
in scientific circles as elusive and imaginary bodies have now been proved to be
definite chemical entities.
It seems that we require some training with regard to our food, otherwise
we feed ourselves wrongly and acquire some disease. Without vitamins we
suffer from certain diseases. If we take too much of them, we suffer from some
other diseases, which are known as ' Hypervitaminosis ', one example of this
being rickets. If you want the formation of heavy and strong bones you want
a lot of vitamin D, but if you take too much of it you get pains all over the body.
One of the worst effects of ' Hypervitaminosis ' is the calcification of the entities—
they become completely calcified and that results in a dreadful disease which
was unknown to our forefathers. The isolation of vitamins in the pure state
has introduced a new source of danger, namely the opportunity it has given to
humanity, particularly faddists, to load themselves with these vitamins and to
* Being extracts from his Readership lectures delivered under the auspices of the
University of Madras on 24th November 1936.
( 133 )