NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
220
Weaned
Versus Unweaned
TABLE V (B)—contd.
The analysis of co-variance of growth rates and initial weights—contd.
Female kids
A
Variation due to
Weaning (between groups)
Within groups . .
Total .
D. P.
1
64
65
S (x 2 )
0.0888
26.2341
26.3229
S (xy)
—0.1867
8.3104
8.1237
S (y 2 )
0.3925
19.7548
20.1473
b
0.3168
0.3086
b. S (xy)
2.6326
2.5071
B
Regression .
.
.
.
.
.
Deviation from regression . . .
Total (within groups) .
1
63
64
S.S.
2.6326
17.1222
19.7548
M. S.
2.6326
0.2718
F. ratio
9.69**
C
Weaning (between groups) . . .
Within groups . . . . .
Total .
1
63
64
0.5180
17.1222
17.6402
0.5180
0.2718
1.91
A. Analysis of co-variance.
B. Test for regression.
C. Analysis of residual variance of the adjusted growth rates.
In the foregoing test, we have not taken into account the initial weights of the kids. Before
drawing any legitimate conclusions, it is necessary to make due allowances for the possible influence
of the initial weight on both average weights and average growth rates. This has been done in the
following analysis by the employment of the analysis of co-variance technique. The results are
conveniently summarized in Table V.
The regressions of average weights and average growth rates on initial weight were found to be
significant for both sexes. The extent of the refinement brought about by the use of this statistical
technique may be deduced from the reductions in standard errors given below :
—
Average weight in lb. per month . . {
Average growth rate in lb. per month . {
Male . . . . . .
Female . . . . . .
Male . . . . . .
Female . . . . . .
Standard Error by
the method of
analysis of
variance
3.65
3.37
0.50
0.56
Standard Error by
the method of
analysis of
co-variance
2.79
2.75
0.46
0.51
222
Weaned Versus Unweaned
such a basis would under-estimate the actual yields. No doubt this method would be to the dis-
advantage of the dams in Group B. Even than, statistical analysis shows, that the average difference
in lactation yields, after correcting for the length of the wet period, between the weaned and un-
weaned groups of animals, is not significant. This finding has to be read in conjunction with what
is said at (b) above. Though no definite conclusions are justifiable, it would appear that probably
the animals get used to the treatment after some time and hence no appreciable difference is introduced
through the 'holding back' of the milk by the dams. Secondly, in any case the part played by
suckling would not be large after the fourth month when the kids in Group B too were weaned. The
average length of lactation of the does in Group B was 220 days which means that the effect of suckling
would be felt only during the first 120 days of the total 220 days.
As regards item v does whose kids were weaned at birth, appear to give on an average (at any
rate in case of does in I, III and IV lactations) larger yields of milk than the does whose kids were
not so weaned. The lactation lengths also were greater. Statistical tests showed that the increased
yields were due to increased lengths of lactations. With the information at our disposal, it is difficult
to say, whether the enhanced wet period is a direct consequence of weaning. On an average, there
was an increase of 56 days in the wet period. The average increase in milk yield was 126 lb. i.e.,
about 2 lb. increase per day increase in wet period. Actually, this figure would be very much less.
An adult doe in milk would take 1 lb. of concentrates and 4 lb. of fodder. Ignoring the housing and
labour charges the cost of producing 2 lb. of milk works out (at the present rates) to about 3 to 4
annas, which appears to be advantageous to the villager, when we consider the price and quality
(especially the latter) of the milk sold in the market. Against this advantage has to be set the cor-
responding delay in getting the new kid, and also the delay in proving of sires.
ACKNOWLEDGEMENT
We are indebted to Dr P. V. Sukhatme for the keen interest he has shown in the progress
of this investigation and for helpful criticism.
REFERENCES
Bhatia, S. S. (1942). Weaning at birth and Hand-feeding of kids. Ind. Farm. 3, 543-44
Etah Goat Breeding Scheme, Annual Progress Reports 1940-1945
Fisher, R. A. (1943). Statistical methods for research workers, Edinburgh
Sukhatme, P. V. (1944). Statistical study of a breeding experiment with goats. Indian J. Vet. Sci. 14, 167-176
PLATE X
[Indian J. vet. Sci., Vol. XVI, Part IV
FIG. 1. Various blocks of Government Cattle Farm, Hissar
FIG. 2. Characteristic lesions in the fourth stomach
A NOTE OF CLINICAL ASPECTS OF ' KHERWAN DISEASE '
By P. N. NANDA, M.R.C.V.S., and H. K. LALL, B.Sc., M.R.C.V.S., Government Cattle
Farm, Hissar
(Received for publication on 8th April 1946.)
(With Plate X and two text-figures)
T HIS disease first occurred in 1940 in the form of an outbreak causing heavy mortality at the
Government Cattle Farm, Hissar at Kherwan block and was named after the place of its
occurrence. In the year 1941 and 1942 there were negligible number of deaths caused by this
disease. In the year 1944 another outbreak occurred in which the mortality figures exceeded the
peak reached in 1940. The disease remained confined to Thaska and Chaoni blocks of the farm
while a few cases occurred at Salli and the Home farm. (For the situation of the places mentioned
in the text, see the Plate X, fig. 1). The other two blocks of the farm, namely the Stables and the
Kherwan, remained absolutely free.
Seasonal incidence. The disease has a seasonal incidence ; each year it has started in the months
of December or January and persisted upto or the middle of May, the peak having reached in the
last week of March and the first week of April. It was observed that in the year 1940 and 1944 the
maximum and minimum temperatures during these months were low as compared with those in the
years 1941, 1942 and 1943 and the rainfall was higher during the months of January, February and
March, the months during which the maximum number of cases were recorded (see Table I and Figs.
1 and 2).
FIG. 1. The weekly mortality figures of Kherwan disease in the outbreaks of 1940-41 and 1944
223
R
224
Clinical Aspects of Kherwan Disease
FIG. 2. Average rainfall and mean temperature during the Outbreak years'
The rainfall was badly distributed in years 1939 and 1943 thus there was a very negligible amount
of grazing left at the end of the year and the beginning of the new year and it is possible that it may
have had an important bearing on the occurrence of the disease. The present (1944) outbreak, similar
to previous ones, was expected to subside by the end of March but the unusual rains in that month
made the weather cool and it continued for a longer period.
Method of spread. The disease seemed to spread rather abruptly from one yard of the block
to another yard and from one block to another block in a sporadic manner—often associated with
virus diseases. That the disease did not spread by direct contact is borne out by the fact that the
healthy animals kept in close contact with the diseased remained unaffected.
Mortality and the course of the disease. The outbreak of 1940 was a very acute one and the an
mals died very suddenly, while in 1944 the course of the disease was rather protracted. A number
of the affected animals recovered but none from the last stage of the disease. In this particular
outbreak Foot and Mouth disease was a complicating factor in the end stages but this did not
cause an obvious increase in mortality.
P. N. NANDA AND H. K. LALL 225
TABLE I
The maximum and minimum temperatures, humidity and rainfall during the years 1940 to 1944
Temperature
Year
1940 . . . .
1941 . . . .
1942 . . . .
1943 . . . .
1944 . . . .
1940 . . . .
1941 . . . .
1942 . . . .
1943 . . . .
1944 . . . .
1940 . . .
1941 . . .
1942 . . .
1943 . . .
1944 . . .
Max.
Min. .
Max. .
Min. .
Max. .
Min. .
Max. .
Min. .
Max. .
Min. .
January
72.3
44.0
67.8
43.9
68.1
40.3
68.4
43.9
69.8
41.6
February
73.5
49.2
78.5
48.6
76.3
48.4
78.9
43.6
74.4
47.4
March
82.7
56.0
91.3
58.5
90.0
56.2
89.7
55.7
83.5
55.3
April
95.7
64.9
May
111
65
June
112
73
Not available
Not available
100.9
70.1
96.1
65.0
96.1
66.7
106.1
78.0
105.6
73.1
108.4
76.3
106.7
81.8
109.8
80.5
104.8
79.8
Humidity
7 a.m.
5 p.m.
..
..
..
..
..
..
..
..
71
48
S4
52
81
54
..
..
79
48
72
41
71
33
79
44
69
27
81
53
59
34
54
25
58
35
50
29
77
52
47
27
46
33
51
39
Not available
Not available
48
30
50
29
59
28
42
22
40
22
43
24
52
65
54
37
60
36
Rainfall
..
..
..
..
..
1.03
3.33
0.22
0.30
0.74
0.88
0.11
0.48
..
1.20
0.69
0.02
..
0.02
1.99
0.11
nil
0.17
Not available
0.79
0.39
1.40
..
1.22
nil
0.78
0.07
1.55
R 2
226
Clinical Aspects of Kherwan Disease
TABLE II
Monthwise mortality (1940-45)
Month
January . . . . .
February . . . . .
March . . . . .
April . . . . .
May . . . . .
June . . . . .
1940
1
35
25
61
12
6
1941
..
19
4
..
..
..
1942
7
..
..
..
..
..
1943
..
1
..
..
..
..
1944
3
16
80
52
11
1
1945
3
15
17
10
3
..
N.B.—Some more cases occurred during May to December 1940 which have not been recorded here because of doubt i n
diagnosis.
In the animals which died, the course of the disease varied in duration from 0 day to 13 days,
but the mean average was 4.4 days, while in the cases which were to recover, the course was more
protracted, lasting for about 19 days (mean average of 39 cases). At Chaoni block 115 fell ill out
of a stock of 994, of which 73 died (63.4 per cent mortality) while 92 recovered.
Age incidence. The ages of the animals that died in 1940 and 1944 were statistically analysed
and it was found that those that died in 1940 were considerably older than the ones that died in 1944
(see Table III). The number of deaths that occurred in various age groups at Chaoni and Thaska
are given in Appendix I.
TABLE III
Statistical analysis of the ages of animals that died
Year
1940 . . . . . . . . . . .
1944 . . . . . . . . . . .
Average age
(in years)
4.913
1.41
Standard
deviation
4.1537
1.265
Coefficient
of variation
84.545
89.717
Symptoms. There were not many characteristic symptoms of the disease which might l ead
one to diagnose it. It was just looking at large number of cases which made on a familiar with the
peculiar attitude of the animals and other characteristic of the disease. In the majority
of the cases in this outbreak, the animals were very emaciated. In the last stage of sickness watery
diarrhoea was a prominent feature and the animal dropped in very exhausted condition never to
get up again. The cattle showed some degree of incoordination in movement but whether this was
due to weakness or some nervous lesions was not very easy to decide. A few of the animals did not
respond to superficial pin-pricks but responded to deep pin-pricks and this loss of sensation extended
all over the body, while in some others there was neither any response to deep non superficial pin-
pricks. The rate of respiration varied within the limits of normality ; it was from 10 to 16 per minute,
The pulse rate varied from 46 to 78. The affected animals stopped feeding absolutely in the end
stages and even the best of the green fodder did not attract them which however, given in early stages
probably had some good effect.
Relapses occurred in two known cases. These animals which had apparently recovered and
were put in with the healthy stock, got an acute relapse after the 23rd day but again made a
recovery.
P. N. NANDA AND H. K. LALL 229
TABLE IV—contd.
Effect of magnesium sulphate drench
No. of animal
4. 158/1.3 . . . . . . . . . . .
5. 60/1.3 . . . . . . . . . . .
6. 446/3.2 . . . . . . . . . . .
7. 348/2.2 . . . . . . . . . . .
8. 431/3.2 . . . . . . . . . . .
Date on which
fell ill
26-5-44
2-5-44
2-5-44
2-5-44
15-5-44
Date of
drenching
5-5-44
5-5-44
5-5-44
11-5-44
16-5-44
Date of
death
16-5-44
29-5-44
8-5-44
29-5-44
18-5-44
In passing we may also mention that on the suggestion of Mr. Shirlaw of the Imperial Veteri-
nary Research Institute, vaccination with brain emulsion was carried out but no definite conclusions
could be arrived at.
SUMMARY
The detailed clinical findings of a disease, called Kherwan disease, after the name of the place
of its occurrence are described. The disease has a seasonal incidence starting in the months of Decem-
ber and January and continuing upto April or May, while its peak is reached at the end of March
or the beginning of April.
2. Two acute outbreaks of the disease have occurred in the years 1940 and 1944 when, in those
particular months rainfall was higher and the maximum and minimum temperatures and humidity
were relatively lower than those in the normal years. It occurred during the years of bad grazing
due to badly distributed rainfall during the previous years.
3. The constant macroscopic lesions were œdema of the alimentary tract particularly in the
folds of the fourth stomach, excess of peritoneal fluid and congestion of all the organs.
ACKNOWLEDGEMENT
We gratefully acknowledge the help and guidance given by Mr J. F. Shirlaw, Pathologist, Im-
perial Veterinary Research Institute, Izatnagar, in carrying out the investigation at Hissar, and also
technical assistance given by Mr Gopal Singh, Veterinary Assistant Surgeon, Hissar.
APPENDIX I
Showing the number of deaths in various age groups in two of the farm blocks
Yard No.
2
3
4
7
8
Total No. of
animals in
the yard
60
3
65
74
36
Date of birth
Chaoni Block
4th quarter 1942
.
.
.
.
.
.
.
.
.
.
....
3rd quarter 1943
.
.
.
.
.
.
.
.
.
.
3rd quarter 1942 .
.
.
.
.
.
.
.
.
....
No. of deaths
1
0
3
2
0
230
Clinical Aspects of Kherwan Disease
APPENDIX I—contd.
Showing the number of deaths in various age groups in two of the farm blocks
Yard No.
9
11
12
13 and 15
16
1
4
5
0
10
11
Total No. of
animals in
the yard
162
25
78
146
87
158
133
170
121
122
89
792
Date of birth
Chaoni Block
1st quarter 1941 . . . . . . . . . .
....
2nd quarter 1943 . . . . . . . . . .
1st quarter 1943 . . . . . . . . . .
2nd quarter 1942 . . . . . . . . . .
Thaska
1st, 2nd and 3rd quarter 1943 . . . . . . . . . .
1st, 3rd and 4th quarter 1942
.
.
.
.
.
.
.
1st quarter 1942 . . . . . . . . . .
2nd quarter 1942 . . . . . . . . . .
4th quarter 1941 .
.
.
.
.
.
.
.
.
.
2nd and 3rd quarter 1941
.
.
.
.
.
.
.
.
No. of deaths
16
5
10
10
48
38
16
3
10
1
1
89
APPENDIX II
Ration statement of Thaska
Age
6—9 months .
1—1½ years .
Ration
Green lucerne and grass . .
Kurbi jowar .
.
.
.
Green berseem . . .
Guar guna
.
.
.
.
Green oats .
.
.
.
Guar bhoosa .
.
.
.
Silage .
.
.
.
.
Kurbi jowar .
.
.
.
Guar guna
.
.
.
.
Green lucerne and grass . .
Green berseem . . .
Green oats .
.
.
.
December
2 sr.
4 „
..
..
..
..
..
..
..
..
..
..
January
..
2 sr.
10 „
1 „
..
..
5 sr.
2 „
1 „
2 „
..
..
February
..
2 sr.
10 „
1 „
..
..
5 sr.
2 „
1 „
2 „
5 „
15 „
March
..
..
..
..
10 sr.
2 „
5 sr.
4 „
..
..
5 sr.
15 „
April
..
4 sr.
..
..
10 sr.
..
..
4 sr.
..
..
5 sr.
5 „
MGIPC—M—III-1-12—2-12-47—520.
P. N. NANDA AND H. K. LALL 231
APPENDIX II—contd.
Ration statement of Chaoni
Age
6 months to 1
year.
1¼ year . .
1¼-2½ year . .
2¼—2½ year . .
Ration
Jowar hay .
.
.
.
Green berseem
Concentrates .
.
.
.
Green rape .
.
.
.
Green raya .
.
.
.
Jowar hay .
.
.
.
Jowar hay .
.
.
.
Green berseem
Lucerne
.
.
.
.
Concentrates .
.
.
.
Jowar hay .
.
.
.
Green rape .
.
.
.
Green oats .
.
.
.
December
2 sr.
5 „
½ „
⅞ „
3
„
3 „
Grazing
alone
„
„
..
..
..
..
January
2 sr.
..
½ „
5 „
..
..
Grazing
alone
„
„
1½ sr.
5 „
5 „
..
February
2 sr.
5 „
½ „
..
..
..
2 sr.
5 „
..
2 sr.
5 „
..
15 sr.
March
2 sr.
5 „
½ „
..
..
..
2
sr.
5 „
5 „
..
..
..
..
April
2 sr.
5 „
½ „
..
..
..
2 sr.
5 „
5 „
..
..
..
..
N.B.—As the disease started in December, ration increased gradually from December to April. It also happened
that the stronger animals got more feed while the weaker ones got left behind and did not get their full share.
234
Subacute Anthrax in Cattle in Madras
if it is administered during the early stage of the disease. He advises the use of one dram of camphor
in 20 c.c. of olive oil subcutaneously and orally with treacle administered every three hours.
In view of some encouraging results obtained previously in Madras with novarsenobillon (May
and Baker), this drug was used in the present outbreak both for affected animals among the non-
vaccinated and also for animals showing temperature from the second day after vaccination. Of
the 15 affected non-vaccinated animals treated, 9 died. Among the vaccinated animals
15 were treated and of these 7 died and 8 recovered. Thus out of 30 animals treated,
16 died and 14 recovered, indicating that novarsenobillon has some value. Before the
investigation started, all the anthrax cases died. There were no natural recoveries in the outbreak
of 1941. An initial dose of at least one gram of the drug is essential and it has a definite curative
value when given intravenously in time.
SUMMARY
An account is given of an outbreak of subacute anthrax among cattle in Madras. The outbreak
occurred in June among animals which had recently suffered from foot and mouth disease and it
lasted for twelve days. The period of incubation appeared to be about three or four days, and an
illness of one to four days was followed by death.
Anthrax serum was found to be valueless for control, but anthrax spore vaccine brought the
outbreak to an end and this in most animals caused no local or thermal reaction. Treatment of affected
animals with novarsenobillon appeared to be effective when the drug was given in the early stages.
ACKNOWLEDGEMENTS
We wish to thank Mr T. J. Hurley, Director of Veterinary Services, Madras, for enabling us
to conduct this investigation, and the Principal, Madras Veterinary College, for confirmation of the
results. The Health Officer, Corporation of Madras, and his veterinary staff co-operated willingly
in this investigation.
REFERENCES
Bachan Singh (1933-34). Annual Report of Veterinary Investigation Officer, Central Provinces and Berar
Gaiger and Davis (1938). Veterinary Pathology and Bacteriology
Hutyea and Mark (1938). Special Pathology and Therapeutics of the Diseases of Domestic Animals, Vol. I
Pande P. G. (1937-38). Annual Report of Veterinary Investigation Officer, Assam
Viswanathan, G. R. (1938-39) Annual Report of Veterinary Investigation Officer, Madras
—
(1941-42). Annual Report of Veterinary Investigation Officer, Madras
I. P. SINGHVERMA, T. M. PAUL, ETC. 237
I. FEEDING OF GROUNDNUT Vanaspathi TO MILCH ANIMALS
A. Cows
(1) Milk yield. The milk yields of the experimental animals were reduced considerably during
the vanaspathi feeding period but the yield of the control animals remained steady throughout with
slight variation. The maximum fall in yield was by about 4 lb. per day in the average daily milk
yield. When the vanaspathi feeding was stopped the milk yield showed a tendency to rise ; but
even after a week the yield remained below the normal level.
(2) Fat output. There was a marked decline in the fat percentage of the milk and combined
with the fall in milk yield this resulted in a net decrease in the average daily fat output. The maxi-
mum fall in fat percentage was 1.8 in one case. The milk yield and fat output are given in Table II.
TABLE II
Average daily milk yield and fat output of cows in gms. during groundnut vanaspathi feeding
Time of taking the sample
Week before vanaspathi
feeding
After five days of vanas-
pathi feeding
After ten days of vanas-
pathi feeding
After 15 days of vanas-
pathi feeding
One week after stopping
vanaspathi
Cow No. 238
M. Y.
4,764
4,694
4,289
3,632
4,313
F.
4.1
3.8
3.4
3.0
3.6
F. Y.
195.1
178.2
145.5
108.9
155.1
Cow No. 251
M. Y.
4,068
3,632
3,250
2,497
2,497
F.
4.5
3.9
3.2
2.7
4.3
F. Y.
182.7
141.5
104.0
67.2
101.0
Cow No. 293
M. Y.
5,221
4,540
3,895
3,360
3,703
F.
4.5
4.2
3.8
3.4
4.7
F. Y.
234.9
190.6
147.8
114.2
173.9
Control group average
M. Y.
4,764
4,764
4,735
4,794
4,740
F.
4.9
4.8
4.9
4.9
4.9
F. Y.
233.2
228.5
231.7
234.7
232.2
M. Y.= Average daily Milk yield. F. Y. = Average daily Fat yield. F. = Percentage of fat.
(3) Composition of the milk fat. There was a marked change in the chemical constants of the
butterfat collected during the experimental period. There was a general decrease in R. M. and
Polenske values, and an increase in iodine value and B. R. reading. In one case the fall in R. M.
value was as great as 13.3 and in Polenske 1.2. The iodine value increased by 9.4 units in one case
and B. R. reading increased by 3.6. Within a week after stopping the vanaspathi feeding the values
returned to normal. In the case of the control animals the analytical constants of the ghee remained
fairly steady throughout the experimental period. The composition of the butterfat is given in Table
III.
TABLE III
Composition of the butterfat during groundnut vanaspathi feeding
Cow No.
238 . . . . . . . . .
Sample
No.
1
2
3
4
5
R. M.
value
33.2
26.5
21.7
19.9
31.1
Iodine
value
33.0
38.7
39.0
42.4
30.2
Polenske
value
2.1
1.8
1.1
0.9
1.2
B. R.
reading
43.6
44.3
46.4
46.4
44.8
238
Influence of Dietary Fat on yield and Composition of Butterfat.
TABLE III—contd.
Composition of the butterfat during groundnut vanaspathi feeding
Cow No.
251
.
.
.
.
.
.
.
.
.
293
.
.
.
.
.
.
.
.
.
Control (average) . . . . . .
Sample
No.
1
2
3
4
5
1
2
3
4
5
1
2
3
4
5
R. M.
value
30.4
20.7
18.5
17.7
30.7
28.8
25.8
24.3
22.3
25.2
27.0
274
27.1
26.9
27.4
Iodine
value
31.5
37.8
39.3
39.5
32.4
40.1
40.9
41.4
41.4
38.4
31.7
31.5
31.3
31.4
31.5
Polenske
value
1.4
0.9
0.8
0.7
1.3
2.0
1.9
1.7
1.6
1.3
2.1
2.1
2.0
2.1
1.9
B. R.
reading
42.8
43.5
45.4
45.5
43.2
43.3
44.5
46.9
46.9
43.5
42.9
42.8
42.9
43.0
42.9
B. Buffaloes
(1) Milk yield. Of the three animals that were under experiment, one animal maintained the
yield for five days and decreased afterwards, whereas the others went down in their average daily
milk yield within five days. The maximum fall in milk yield was by 2| lb. in one case. Even after
stopping the oil feeding the yield did not return to normal for one week in the case of the experi-
mental animals. The control animals maintained their yield except for a small fall in the yield to-
wards the end which may have been due to advance in lactation.
(2) Fat output. The fat percentage of the milk showed a slight but definite increase during the
vanaspathi feeding, the maximum being by 1.5 per cent. in one case. But this altered the output
of butterfat only to a small extent because the yield of milk had gone down considerably. After the
stopping of the oil feeding the fat percentage returned to normal within a week. There was no
marked change in the fat percentage of milk or in the output of fat in the case of the control animals,
The yield of milk and butterfat are given in Table IV.
TABLE IV
Milk yield and fat output of buffaloes in gm. during groundnut vanaspathi feeding
Time of taking sample
Week
before
feeding
vanaspathi
5 days after feeding
10 days after feeding
15 days after feeding
One week after stopping
feeding
Buffalo No. 57
M. Y.
9,080
8,204
7,948
7,948
8,172
F.
5.1
6.2
6.3
5.4
5.4
F. Y.
463.0
512.1
500.2
508.1
441.2
Buffalo No. 58
M. Y.
7,946
7,626
7,626
7,626
7,918
F.
6.7
7.4
7.5
7.5
7.0
F. Y.
531.9
563.8
571.5
571.5
553.1
Buffalo No. 93
M. Y.
9,988
9,988
9,080
8,718
8,918
F.
5.4
6.1
6.8
6.9
6.3
F. Y.
538.9
608.7
617.4
600.9
561.3
Control (Average)
M. Y.
6,129
6,183
6,129
6,129
5,962
F.
6.9
7.0
7.0
7.0
7.1
F. Y.
422.2
432.6
428.4
428.4
423.1
M. Y. = Average daily milk yield. F. Y. = Average daily fat yield. F.= Fat percentage.