H. C. VERMA, ZAL R. KOTHAVALLA AND E. V. SESHACHARYULU 225
Dairy Institute Farm. The houses had tiled
roofs, closed sides, kachcha flooring and poor
drainage. Well water was used for watering
the animals and for cleaning purposes. The
cattle houses were merely swept; the manure
was allowed to lie nearby. Ordinary vessels
were used for milking and handling of the milk
and their cleaning done by the indigenous
method. The animals were washed occasional-
ly in most cases, their feeding was done during
milking and milking was performed in an un-
clean manner. Samples of bulked milk were
taken for examination. Each sample represent-
ed the production of about 20 animals.
(vii) Domestic cows. The udders of the
cows were washed with tap water. After
the calves had been sucked, milking was done
in brass vessels with small openings. Clean-
ing of the milking vessels was done by
scouring with ash and mud, rinsing out
with water and finally draining and drying them
in shade. The vessels were rinsed out with the
tap water before use. Samples for examination
were taken from the milking vessels on comple-
tion of each milking.
In this work samples of only morning produc-
tion and supply were taken. The atmospheric
temperatures at the time varied from 75°F. to
85°F. Although the Imperial Dairy Institute
sells pasteurized milk, samples of only raw milk
before pasteurization were examined to compare
the quality obtainable under farm conditions
with the other sources of supply. All the
samples, other than those taken at the Imperial
Dairy Institute cattle yard and dairy, were
brought to the laboratory in ice boxes and exa-
mined, within about half an hour of sampling,
for Methylene Blue Reduction time and
bacterial count. The Methylene Blue Reduc-
tion test was performed according to Wilson's
modified technique [1935] and the bacterial
count was determined by the plate method using
milk agar as recommended by the Ministry of
Agriculture [1934]. A total of 1340 samples
taken, both from the production and supply ends
was examined. The results obtained are given
in Tables I and II respectively.
RESULTS AND DISCUSSION
The results of the tests with the samples at
production (Table I) show that, under the condi-
tions obtainable on the Imperial Dairy Institute
Farm (representing standard dairy farm condi-
tions), a majority of the milk samples (86.72
per cent.) of individual cows and buffaloes con-
tained under 50,000 bacteria per ml. This also
included a very large proportion of samples
giving under 25,000. The majority of herd
samples (cow and buffalo) contained between
25,000 and 100,000 bacteria per ml. The pro-
portions of cow herd samples giving a count
below and above 100,000 were 91.05 per cent.
and 8.92 per cent. and of buffalow herd samples
84.05 per cent and 15.92 per cent respectively.
All samples of domestic cows gave count upto
100,000 bacteria per ml. except for one sixth of
the total number which gave between 100,000
and 200,000. No sample of milk from town
milk stables contained below 100,000 bacteria
per ml. A little more than half of the total
number of these had between 200,000 and.
500,000 and the remaining between 500,000 and
5 millions bacteria per ml. The majority of
village milk samples contained between 500,000
and 10 millions bacteria per ml. and only
about one-sixth of the total number had between
200,000 and 500,000.
The methylene blue reduction times of 88.66
per cent. of the samples of individual cows and
buffaloes was about 330 min. (5½ hr.) and of
this over half the number were above 420 min.
(7 hr.). The remaining were decolourized
between 329 and 240 min. (5½ hr.—4 hr.).
Taken separately the reduction time of above
and below 330 min was recorded in case of
90.74 per cent and 9.24 per cent of cow milk
samples and 84.33 per cent and 15.66 per cent
of buffalo milk samples respectively. All the
herd milk samples (cow and buffalo) decolour-
ized between 240 and 419 min. (4–7½hr.); of
these more than half of the total number were
between 240 and 329 min. (4—5½hr.) only one
sample being above 420 min. and two below 240
min. The proportions of the cow herd samples
with reduction times above and below 330 min.
were 44.61 per cent. and 55.38 per cent. and
of buffalo herd samples 38.93 per cent. and 61.06
per cent respectively. All the samples of
domestic cows decolourized between 240 and
419 min. (4—7½ hr.); of these a large proportion
were between 240 and 329 min. (4—5½ hr.). The
reduction time of a majority of samples of town
milk stables was between 120 and 239 min. (2-4
hr.). an appreciable number being between 240
and 329 min. (4—5½ hr.). The number of samples
above 329 min. was negligible. The majority of
village milk samples decolourized between 60
and 179 min. (1—3 hr.), about two-fifths of the
total number were between 180 and 329 min.
3—5½ hr.) and a negligible proportion below
60 min.