NationalLibraryOfScotland/medical-history-of-british-india huggingface dataset:
106
PROTEINS FOR EGG PRODUCTION
[Vol. XX, Part II,
made of dried grass and bamboo gave better protection against sun and rain. The
run itself was enclosed on the four sides by means of wire netting. On one side of
the enclosure there was a gate for entrance.
Feeding. All the five groups were fed on mash only. Besides the mashes each
of the pens was provided with broken limestone and water ad lib. Liberal amounts
of succulent green food were also given every afternoon. The basal mash used was
of the following composition :
Wheat bran
......
Yellow maize meal
Ground oats .................
Ground jowar
......
25 parts
35 do.
......15 do.
5 do.
Group 1 (basal group) was fed the basal mash supplemented with 0.5 per cent
common salt. This group served as the negative control. Group 2 (rape cake
group) received a ration containing 79.5 parts basal mash, supplemented with 20
parts rape cake meal and 0.5 part common salt. Group 3 (earthnut group) was
fed on a ration consisting of 84.5 parts of basal mash, 15 parts of earthnut meal and
0.5 part of common salt. Group 4 (fish meal group) was fed on a ration consisting
of 84 parts basal mash and 16 parts fish meal. Group 5 (meat offal group) received
the basal mash supplemented with 1 to 1.1 oz. of meat offal per bird per day.
Group 1 to 4 were fed dry mash ad lib. in waste proof hoppers. The meat offal
was minced and cooked for about an hour, with a small quantity of water The
cooked material which became very soft, together with any liquid material that
was left over, was mixed with some quantity of dry mash approximately in the
proportion of 1.5 oz. dry mash for 1 oz. of meat offal per bird per day. The quantity
of meat offal was adjusted from day to day to bring up to the required protein level.
This was fed as wet mash in open hoppers at 4 p.m. every day before the birds went
to roast. This wet mash was so much relished that the whole quantity was
consumed in about fifteen minutes.
The average composition of the mashes is given in Table I.
TABLE I
Percentage chemical composition of the feeds
Feed
Groups 1 and 5
Basal mash + salt
Group 2
Basal mash + rape cake meal
+ salt
Group 3
Basal mash + earthnut meal
+ salt
Group 4
Basal mash + fish meal + salt
Moisture
10.12
10.02
10.21
10.05
Crude
protein
9.50
14.71
14.50
14.38
Ether
extract
4.10
5.14
5.02
4.23
Fibre
6.75
6.02
5.91
5.75
Ash
5.60
5.84
7.32
10.18
Nitrogen
free
extract
63.93
58.27
57.04
54.81
June, 1950]
D.
PARTHASARATHY
AND
S.
G.
IYER
107
RESULTS
Production. Table II gives the total egg production of each group for each
period of 2 weeks and the total average egg production of a bird for the total period
of 12 weeks.
TABLE II
Average egg production per bird
Group
Protein supplement
1st period
2nd period
3rd period
4th period
5th period
6th period
Total
1
None
1.4
1.4
2.8
4.0
3.7
3.6
16.9
2
Rape cake
2.8
4.0
5.8
8.2
8.2
4.2
33.2
3
Earthnut
meal
3.0
4.1
5.7
5.9
5.9
2.9
27.3
4
Fish meal
4.0
5.0
5.4
6.1
6.1
4.8
31.1
5
Meat offal
3.5
4.3
7.6
7.3
7.3
3.8
34.4
It would be seen that the highest egg production in nearly all the groups was
obtained in the 3rd, 4th and 6th periods. There was some how a drop in the pro-
duction in all the groups during the 6th period. The average egg production figures
for a period of 12 weeks were 16.9 : 33.2 : 27.3 : 31.1 : and 34.4 in groups 1, 2 3,
4 and 5 respectively. As was expected there was marked difference in the produc-
tion figure of group 1 (negative control) and other groups.
Egg weight. Table III gives the average egg weight for each group for each of
the fortnightly periods and the average weight for the total period of 12 weeks.
F 2
108
PROTEINS
FOR
EGG
PRODUCTION
[Vol. XX, Part II,
TABLE III
Average egg weight (oz.)
Group
1st period
2nd period
3rd period
4th period
5th period
6th period
Average for the 12 weeks
1
1.99
2.08
2.05
2.03
1.95
1.99
2.02
2
1.98
2.02
2.08
2.07
2.04
1.98
2.03
3
2.04
2.06
2.07
2.11
2.12
2.07
2.08
4
2.17
2.10
2.09
2.08
2.09
2.11
2.11
5
2.03
2.04
2.03
2.09
2.07
2.04
2.05
There were variations in the weight of eggs in each of the groups in the various
periods. The maximum average weight (2.11 oz.) was obtained in Group 4 (fish
meal).
Food consumption. Table IV gives the average daily food consumption for
the total period of 12 weeks as well as daily food consumption in the respective
groups per bird.
TABLE IV
Food consumption
Group
Total consumption of mash
per bird (lb.)
Meat offal consumed per bird
(lb.) fresh basis
Total food consumption per
bird (lb.)
Average daily food consump-
tion per bird (oz.)
1
21.32
..
21.32
4.04
2
22.83
..
22.83
4.36
3
22.13
..
22.13
4.20
4
22.70
..
..
22.70
4.32
5
19.00
8.10
21.43
4.08
It will be seen that in group 2 there was maximum food consumption per bird
group 4 following next. There were no significant differences in groups 1 and 5.
For the sake of uniformity the meat offal consumed in group 5 was reckoned on a
dry matter basis of 30 per cent.
The efficiency with which the food was utilised for egg production, as expressed
by the weight of feed required to produce one egg is given in Table V.
June, 1950]
D.
PARTHASARATHY
AND
S.
G.
IYER
109
TABLE V
Number of pounds of feed consumed for 1 egg produced
Group
Total egg production per bird
Total quantity of feed con-
sumed (lb.)
Number of lb. feed required to
produce 1 egg
1
16.9
21.32
1.26
2
33.2
22.83
0.69
3
27.3
22.70
0.81
4
31.1
22.70
0.73
5
34.4
21.43
0.62
The values are calculated from Tables I and IV.
Mortality. Mortality figures are given in Table VI.
TABLE VI
Mortality and body weight
Group
Number of birds at start
Number of birds died
Average weight at start (lb.)
Average weight after 4 weeks
(lb.)
Average weight after 8 weeks
Average weight after 12 weeks
Average gain in weight during
experiment
1
52
..
4.81
5.13
5.40
5.50
0.69
2
54
1
4.80
5.10
5.38
5.47
0.67
3
53
..
5.02
5.10
5.30
5.34
0.32
4
51
1
4.90
4.88
5.04
5.16
0.26
5
52
2
4.87
5.87
5.28
5.40
0.53
There was no mortality in groups 1 and 3. In groups 2 and 4 there was only
one death in each. In group 5 two birds were lost, one of which died because of
an accident and so in this group also the actual loss may be considered as only one.
The birds were weighed at the beginning of the experiment and thereafter at
intervals of 4 weeks. The average weight of the birds in each group at the beginning
and at various intervals are given in Table VI. The birds maintained good condi-
tion throughout and in every group there was some gain in weight during the experi-
mental period.
DISCUSSION
The groups fed on protein supplements whether of vegetable or animal origin
gave better egg production than the one without. In group I the egg production
was 16.9 (lowest) for a period of 12 weeks or on percentage basis, 20.1 per cent.
June, 1950] D. PARTHASARATHY AND S. G. IYER 111
quality. It is significant that rape cake meal was very efficient and exceeded the
fish meal which was used in this experiment. As expected group 1 on basal mash
alone had the lowest efficiency.
The general health of the birds was quite satisfactory. Deaths were due to
accidents or simple causes like egg peritonitis and colds. In all the groups there
was an increase in body weight during the period of experiment. It is to be noted
that in group 1 there was maximum gain. Next in order came groups 2 and 5.
It is somewhat significant that in spite of greater production involving some strain
on the body both groups 2 and 5 were able to put on some weight during the
period of the experiment, particularly group 2. On the whole all the groups
maintained good health and no untoward effects were found.
SUMMARY
An experiment on the comparative values of rape cake meal, earthnut meal,
fish meal and meat offal as protein supplements to a laying ration was for a period
of 12 weeks, with Rhode Island Red pullets. The maximum production was obtained
with meat offal, rape cake meal coming next. Fish meal and earthnut meal followed
in order. No significant differences in egg size were observed among the groups.
Food consumption was a little high in rations containing rape cake and fish meal.
The efficiency of food utilisation as expressed by the number of pounds of feed to
produce one egg was highest with meat offal, rape cake, fish meal and earthnut
meals following in order. The general health was satisfactory in all the birds.
REFERENCES
Hill, D. C. (1944). Scientific Agriculture 24, 576
Macdonald, A. J., Bose, S. (1943). Indian J. vet. Sci. 13, 150
Marble, D. R., Nicholas, J. E., and Knandel, H. C. (1938). Penn. Ag. Exp. Sta. Bull. (367), 55
Mukherjee, R. and Parthasarathy, D. (1948). Indian J. vet. Sci. 18, 51
RESEARCH INTO INDIAN CITY MILK
I. CHEMICAL AND BACTERIOLOGICAL EXAMINATION
By R. N. NAIK, G.B.V.C., Vice-Principal and Bacteriologist, D. T. PARNAIK.
G.B.V.C., Assistant Bacteriologist and P. R. DHAKE, G.B.V.C., Graduate
Assistant, Bombay Veterinary College, Parel
(Received for publication 1 May 1948)
J OSHI [1916] collected 68 samples of milk from the stables of Bombay city and
reported an average of 17,103,000 bacteria per ml. in them. He also carried out
bacterial counts of 240 samples of milk collected at random from certain stables,
dairies, milk hawkers and milk shops of Bombay city and found on an average
36,385,000 bacteria per ml. in them. Walton [1925 and 1927] studied the bacterial
contents of milk produced at the Agricultural Research Institute Dairy, Pusa and
reported that the total bacterial and coliform counts varied seasonally, the highest
number occurring during the rains. The Annual Report of the Imperial Dairy Expert
[1939] stated that the average plate count of milk produced at the Imperial Dairy
Institute, Bangalore, was 235,000 per ml. and that the methylene blue reduction
time was four hours. Verma, Kothavalla and Seshacharyulu [1945] determined
plate counts of bacteria in milk samples collected both at the production and
at the supply end at Bangalore city from the Imperial Dairy Institute
and from the travelling milch cows showed a plate count below 500,000 per ml. and
a. methylene blue reduction tim above four hours; the milk samples from milk
hawkers had a plate count between 500,000 and five millions per ml. and a methylene
blue reduction time of less than three hours ; and milk samples from town dairies
had a plate count between one million and over 90 millions and a methylene blue
reduction time below two hours. They found further a better correlation between
the methylene blue reduction time of four or more hours and 200,000 or less plate
counts of bacteria than between the reduction time of five and a half or more
hours and 200,000 or less plate counts of bacteria.
Milk is one of the essential protective foods, judging the quality of which is an
important problem. The quality is judged by determining the chemical consti-
tuents and bacterial contents of milk. The bacteriological examination is an in-
dispensable necessity to safeguard the public health and to ensure keeping qualities
of milk. It is a known fact that milk contaminated with pathogenic microorganisms
which may be found in faeces of persons suffering from intestinal diseases or of persons
who are carriers of the disease is dangerous for human consumption. But few have
attempted to identify the bacteria found in milk supply of big cities in India or have
carried out coli tests, etc., which are useful in evaluating the quality of milk. Forty
samples of milk marketed in Bombay city were, therefore, subjected to almost all
chemical tests and bacteriological examinations and the results obtained are reported
in this paper.
113
G
June, 1950] R. NAIK, D. PARNAIK AND P. DHAKE 115
4. and 5. The solids-not-fat and water. The solids-not-fat was calculated simply
by deducting the fat percentage from the total solids and the water by deducting
total solids from 100.
Bacteriological tests
Bacterial count. This was done by adopting the method of the standard plate
count described in the Laboratory methods of the United States Army by
Simmons and Gentzkow [1946]. The milk agar medium contained agar 15 gm.,
beef extract 3 gm., peptone 5 gm., glucose 1 gm. and distilled water 1,000 c.c. The
dilution used for plating were 1 in 100, 1 in 1,000 and 1 in 10,000. The colonies of
bacteria were counted only on those plates which showed 30 to 500 colonies or nearest
to 500 according to the method stated in the English milk order [Mackie and
McCartney, 1946].
Coliform test
This test is carried out to estimate the degree of contamination present, a high
degree of which renders the milk unsatisfactory for human consumption. The
method described by Gaiger and Davis [1947] was adopted to carry out the test.
Three tubes each containing 5 c.c. of McCartney broth culture medium were taken
and 1 c.c. of 1/100 dilution of milk in sterile water was transferred into each of them.
The culture tubes were incubated at 37°C. for 48 hours and then examined for acid
and gas production, when two out of three tubes were found to be free from both
acid and gas, the milk was regarded as satisfactory.
Methylene blue reduction test
This test is used in conjunction with Coliform test. The test was carried out
according to the standard official method of England described by Mackie and
McCartney [1946]. As methylene blue tablets were not available here methylene
blue (methylthionin chloride) made by Boots Pure Drugs Co., Ltd., was used. A
1:20,000 solution of the dye was prepared and a part of this solution was heated to
100°C. for a few minutes before use. Two control tubes of milk one containing in
addition 1 c.c. methylene blue solution and the other 1 c.c. of tap water were prepared,
immersed in boiling water for 3 minutes and used for comparison.
Cultural examination
With a view to finding out the micro flora of milk samples marketed in big cities
by actual identification of the individual species every milk sample was centrifuged
and the centrifuge deposit was subjected to cultural examination. The cultures
were made on nutrient agar and blood agar media in series for growing single Colonies
and incubated at 37°C. under aerobic conditions only.
Rapid Platform tests
Alcohol test. This test detects the abnormal quantity of acid i.e., more than
0.21 per cent of calcium and magnesium. The method used was that recommen-
ded by Eckles, Comb and Harold Macy [1943]. Ten c.c of 75 per cent alcohol and
10 c.c. of milk were taken together in a test tube which was inverted several times
G2
116
RESEARCH INTO INDIAN CITY MILK
[VOL. XX, PART II
and observed for the production of coagulation or fine particles of curd, which
denotes the abnormal nature of milk.
Phenolphthalein test. This test is performed to note the abnormal percentage of
lactic acid present in the milk as a result of the bacterial activity. The method
adopted was that recommended by Eckles, Combs and Harold Macy [1943]. 17.6 gm.
of milk were taken, 5 drops of 1 per cent alcoholic solution of phenolphthalein added
to it and then N/10 sodium hydroxide solution was added to the same through a
burette in drops until a persistent pink colour appeared. The percentage lactic
acid was calculated according to the following formula.
Percentage lactic acid = c.c. N/10 sodium hydroxide x 0.009 x 100/grammes of milk
RESULTS
The results of the chemical tests are given in Table I.
The total count of viable bacteria and the classification of milk samples on the
basis of bacterial count and dye reduction tests are given in the Table II.
The results of Coliform tests and of rapid platform tests are given in the Table III.
The classification of milk samples based on their chemical composition is given
in the Table IV.
The classification of milk samples based on their bacteriological quality is set
out in the Table V.
The results of the cultural examination carried out to study the flora of milk
samples which were used in these experiments will be reported in a subsequent article
as the work connected with it has not been completed, as yet.
DISCUSSION
It is observed from these findings that the standard plate count of milk samples,
collected in Bombay city market, was not high according to the classification adopted
in this study. All milk samples fell under Class I or 'good milk' and Class II or
'milk of a fair average quality' except about seven per cent of the samples. There
were only 3 out of 40 samples which were classed as Class III or ' bad milk' and
there were no 'very bad milk' samples classified either according to the plate count
or the methylene blue reduction test. The average bacterial counts of milk from
buffalo stables were 1,475,533 and that from milk vendors 1,368,800. Joshi [1916] has
recorded in the city of Bombay an average plate count of 17,000,000 and 36,000,000
of bacteria per c.c. of milk from the city stables and milk vendors respectively.
Our results do not, therefore, confirm Joshi's findings. Perhaps it may due to the
fact that our investigation having been undertaken during winter. Our results
are, however, in line with the findings recorded in Bangalore city by the Imperial
Dairy Institute [1939].
The results on the composition of milk marketed in the Bombay city have yielded
very interesting results. Milk rich in fat, high in total solids and normal in water
contents, generally showed higher plate counts of bacteria per c.c. than those milk
samples which were poor in fat and total solids and which contained more water
June, 1950]
R.
NAIK,
D.
PARNAIK
AND
P.
DHAKE
117
TABLE I
Chemical analysis of some milk samples marketed in the Bombay
City
Source
of
milk
Buffa1o
stable
Milk vendor
Total
number
of
samples
15
(100 per
cent
25
(100 per
cent)
Specific gravity
1.027
or
above
10
(66.7 per
cent) 6
(20 per
cent)
Less
than
1.027
5
(33.3 per
cent) 19
(80 per
cent)
Average
1.030
1.025
Fat
Between
6.5
and
8 per
cent
5
(33.3 per
cent) 1
(4 per
cent)
Between
3.5
and
6.5 per
cent
9
(60 per
cent) 12
(48 per
cent)
Below
3.5 per
cent
1
(6.7 per
cent) 12
(48 per
cent)
Aver-
age
6.47
3.73
Total solids
17 per
cent
and
above
12
(80 per
cent)
..
Less
than
17 per
cent
3
(20 per
cent) 25
(100 per
cent)
Aver-
age
16.1
10.8
Solids-not-fat
Between
10
and
11 per
cent
3
(20 per
cent)
..
Less
than
10 per
cent
12
(80 per
cent) 25
(100 per
cent)
More
than
11 per
cent
..
..
Aver-
age
9.0
6.14
Water
Less
than
83 per
cent
7
(46.7 per
cent)
..
Above
83 per
cent
8
(53.3 per
cent) 25
(100 per
cent)
Aver-
age
83.86
89.2
TABLE II
Classification of milk samples on the basis of bacterial contents and dye reduction
capacity
Source
of
milk
Buffalo stables
Milk vendors
Total
Total
number of
samples
15
25
40
Total count of viable bacteria
Minimum
per ml.
104,000
51,000
..
Maximum
per ml.
4,120,000
8,640,000
..
Average
per ml.
1,475,533
1,368,800
..
Classification according to bacterial plate count
Class I
Good milk
500,000
bacteria
per ml.
4
(26.7 per
cent) 9
(36 per
cent) 13
(32.5 per
cent)
Class II
Fair milk
(average
quality)
500,000
to 4
million
bacteria
per ml.
10
(66.7 per
cent) 14
(56 per
cent) 24
(60 per
cent)
Class III
Bad
milk
4 to
20 million
bacteria
per ml.
1
(6.7 per
cent) 2
(8 per cent)
3
(7.5 per
cent)
Class IV
Very bad
20 million
bacteria
per ml.
..
..
..
Classification according to methylene blue
reduction time
Class I
Not
reduced
in 5½
hours
6
(40 per
cent) 8
(32 per
cent) 14
(35 per
cent)
Class II
Reduced
in less than
5½ hours
but not
less than
2 hours
8
(53.2 per
cent) 16
(64 per
cent) 24
(60 per
cent)
Class III
Reduced in
2 hours
1
(6.7 per
cent) 1
(4 per
cent) 2
(5 per
cent)
Class IV
Reduced in
20 minutes
..
..
..
(Figures in brackets indicate the number of the samples in that category expressed as per cent)
118
RESEARCH INTO INDIAN CITY MILK
[VOL. XX, PART II
TABLE III
Showing the results of coliform test and other bacteriological tests
Source of milk
Buffalo stables
Milk vendors
Total
Total
number of
samples
15
(100 per
cent)
25
(100 per
cent)
40
Coliform Test
Negative
or
satisfactory
..
5
(20 per
cent)
5
Positive
or not
satisfactory
15
(100 per
cent)
20
(80 per
cent)
35
Alcohol test
Negative
3
(20 per
cent)
16
(64 per
cent)
19
Positive
12
(80 per
cent)
9
(36 per
cent)
21
Phenolphthalein test
for acidity
18 and below
5
(33.3 per
cent)
20
(80 per
cent)
25
Above 18
10
(66.7 per
cent)
5
(20 per
cent)
15
Classification of milk samples on the basis of bacterial contents and dye reduction capacity.
June, 1950]
R.
NAIK,
D.
PARNAIK
AND
P.
DHAKE
119
TABLE IV
Classification of milk samples based on their chemical composition
Source of milk
Buffalo stables
Milk vendors
Classification accord-
ing to plate count
Class I—good milk
Class II—fair average
quality
Class III—bad milk
Class IV—very bad
milk
Total
Class I—good milk
Class II—fair average
quality
Class III—bad milk
Class IV—very bad
milk
Total
Fat
Between
6.5 and 8
per cent
2
4
..
..
6
..
..
..
..
..
Less than
6.5
per cent
2
6
1
..
9
9
14
2
..
25
Total solids
17 per
cent and
above
1
6
..
..
7
..
..
..
..
..
Less than
17
per cent
3
4
1
..
8
9
14
2
..
25
Solid not fat
Between
10 and 11
per cent
1
2
..
..
3
..
..
..
..
..
More
than 11
per cent
..
..
..
..
..
..
..
..
..
..
Less than
11
per cent
3
8
1
..
12
9
14
2
..
25
Water
under
83
per cent
1
6
..
..
7
..
..
..
..
..
More than
83
per cent
3
4
1
..
8
9
14
2
..
25
120
RESEARCH INTO INDIAN CITY MILK
[VOL. XX, PART II
TABLE V
Classification of milk samples based on their bacteriological quality
Source of milk
Buffalo stables
Milk vendors
Classification according to plate
count
Class I—goad milk
Class II—fair average quality
Class III—bad milk
Class IV—very bad milk
Total
Class I—good milk
Class II—fair average quality
Class III—bad milk
Class IV—very bad milk
Total
Alcohol test
Negative
3
..
..
..
3
7
8
1
..
16
Positive
1
10
1
..
12
2
6
1
..
9
Phenolphthalein test for
acidity
Normal
3
..
..
..
3
9
9
2
..
20
More than
normal
1
9
1
..
11
..
5
..
..
5
Coliform test
Satis-
factory
..
..
..
..
..
3
2
..
..
5
Unsatis-
factory
4
10
1
..
15
6
12
2
..
20
June, 1950]
R. NAIK, D. PARNAIK AND P. DHAKE 121
than normal. Further it may be observed that the milk from buffalo stables
passing to the consumers direct or through the Government subsidised milk shop
was the best and was in accordance with the average quality milk of buffalo except
in water contents in about 50 per cent of samples. But the vendors' milk was in
almost all instances very poor in all chemicals composition (Table I).
It is common knowledge that in advanced nations, the quality control of milk
is insisted upon all marketed milk and the easiest time saving method of estimating
the extent of bacterial activity or contamination in the town where a laboratory is
not available for carrying out bacterial count is methylene blue reduction test. In
the Scandinavian countries the following standards are used according to stitt
Clough and Clough [1943].
Classification
Class I—good milk under 500,000
bacteria per c.c. (according to plate
count.)
Class II—milk of fair average quality
500,000 to 4,000,000 bacteria per
c.c.
Class III—bad milk 4,000,000 to
20,000,000 bacteria per c.c.
Class IV—very bad milk 20,000,000
or more bacteria per c.c.
Methylene blue reduction time
Not reduced in 5½ hours.
Reduced in less than 5½ hours; but
not less than 2 hours.
Reduced in less than 2 hours ; but
not less than 20 minutes.
Reduced in 20 minutes.
In the results presented the correlation between plate count and methylene
blue reduction time of the milk samples was the same as stated in the above table
with the exception that the reduction time was less than 5½ hours in 50 per cent
of samples classed under Class I, good milk.
SUMMARY
Forty samples of milk comprising of 15, drawn from buffaloes and 25 collected
from milk vendors in Bombay city have been subjected to bacteriological and
chemical tests during winter.
From the point of view of the composition, the milk collected from buffalo stables
distributed to the public directly or through the Government subsidised shops was
found to be the best and conformed with the average quality of buffalo milk except
in water contents in about 50 per cent samples. But the vendor's milk was found
to be heavily adulterated with water as in all these cases there was a decreased per-
centage of fat and total solids. The absence of an increase in the solids-not-fat
in all milk samples indicated that fat had not been removed in any sample.
The average standard plate counts of buffalo stables milk and of vendor's milk
were 1,476,533 and 1,368,800 per ml. respectively.
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