COMPARATIVE VALUES OF PROTEINS FOR CHICKENS
By A. J. MACDONALD, Poultry Research Section, Imperial Veterinary Research Institute, Izatnagar
(Received for publication on 23 January 1943)
THE necessity of including adequate amounts of
protein of high biological value in the ration of
growing chickens is now recognized wherever
poultry-keeping is a well-developed and specialized
occupation. In India, however, the need for
feeding chickens on well-balanced rations, es-
pe cially during the early stages of growth, is not
widely appreciated, particularly in the villages.
As the feeding of badly balanced rations to chickens
results in high mortality rates, poor growth,
delayed sexual maturity and poor utilization of
the food consumed, it is essential to carry out
experim ental work in order to discover cheap and
reliable rations. In earlier experiments, Macdo-
nald [1941] found that cereal rations in con-
junction with calcium and green food could be
effectively balanced by feeding separated milk
ad libitum during the early stages of growth.
From six weeks onward satisfactory results were
obtained by feeding cereals and liberal amounts
of calcium and green food, together with separated
milk and water in separate containers. It was
also found that soya bean meal plus salt might
be used with fairly satisfactory results whenever
milk supplements were expensive or difficult to
obtain. Later, Macdonald [1942] found that a
supplement of earthnut meal and salt, though
not so good as separated milk, could be used with a
fair measure of success.
In the experiment under report, it was decided
to test out the relative values of supplements of
separated milk, soya bean meal, earthnut meal
and meat offal. The feeding of meat offal to
poultry is at present practised by a limited
number of poultry keepers, but so far no precise
information is available in regard to its value,
either in this country or abroad.
METHODS
Stock. A total of 345 day-old, White Leghorn
chicks, hatched in December, 1941, were divided
into five comparable groups and fed on the ex-
perimental diets for a period of 20 weeks.
Feeding. All the birds were fed on mash and
grain rations. Supplementary calcium, as broken
limestone was fed ad libitum and succulent cut
green food was fed in adequate amounts once
daily during the whole experiment. A basal
mash consisting of wheat bran 50 parts, yellow
maize meal 30 parts and ground oats 20 parts was
fed to all the groups. During the first eight weeks,
the grain ration consisted of equal parts of broken
yellow maize, jowar and cheena and from eight
weeks onward the grain ration consisted of equal
parts of broken yellow maize, wheat and paddy.
The grain was fed four times a day during the first
week and thereafter it was fed in the morning
and evening, according to appetite.
Group 1 was not given any protein-rich supple-
ment, but the mash was supplemented by one per
cent common salt. Group 2 received the basal
mash plus 0.5 per cent common salt throughout,
along with separated milk only to drink from
0-12 weeks and separated milk and water in sepa-
rate containers from 12-20 weeks. Group 3 was
fed on a mash consisting of 82 parts basal mash
supplemented with 17 parts earthnut meal and
one part common salt. Group 4 was fed 74 parts
basal mash supplemented by 25 parts soya bean
meal and one part common salt. Groups 1-4
were fed dry mash ad libitum in suitable sized
hoppers throughout the experiment. Group 5
was fed the basal mash plus one per cent common
salt throughout, together with meat offal (cleaned
intestines of animals from the slaughter house).
The meat offal was run through a mincing machine
and cooked for one hour in a small quantity of
water prior to mixing with the mash. The meat
offal and the liquid residue after cooking were
mixed along with the required quantity of mash
and the whole mixture fed in a crumbly state.
The wet mash required for one day was made up
in the morning and equal amounts were fed at
8 a.m., 11 a.m. and 2 p.m. From 0-12 weeks the
birds received the wet mash mixture in the pro-
portion of 3/4 lb. meat offal to 1 lb. of dry mash.
From 12 weeks onward ½ lb. of meat offal was
added to every 1 lb. of dry mash.
Table I gives the average composition of the
mashes and grains fed during the experiment.
The average composition of the separated milk
was moisture 90.3 per cent and crude protein
3.7 per cent. The average composition of the
meat offal was moisture 75 per cent and crude
protein 15.3 per cent.
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