EFFECT OF AUREOMYCIN AND VITAMIN B 12 ON THE
GROWTH OF WEANED PIGS FED A HIGH-PROTEIN DIET
By ALEX REED1 AND O. P. AGARWALA2, Agricultural Institute, Allahabad
(Received for publication on April 24, 1956)
(With one text-figure)
T is generally agreed that the use of aureomycin or terramycin tends to increase
the rate of gain in weight when fed to growing pigs. Catron et al., [1952] found that
when fed 10 mg. aureomycin per pound of ration, the pigs gained an average of 0.12
lb. more per day and consumed 2.3 lb. less feed per 100 lb. gain than the pigs receiving
the antibiotic. Burnside et al., [1951] compared the effect of aureomycin when fed
with high, intermediate and low protein levels and concluded that the aureomycin
improved all rations. Hoeffer et al., [1952] fed terramycin at 5 mg. per lb. of total
ration and observed a highly significant effect on the rate of gain and also improved
efficiency of the gain. Terrill et al., [1952] fed 5 mg. aureomycin hydrochloride per
lb. of a 20 per cent crude protein " corn, solvent-soybean-oil-meal", ration properly
fortified with minerals and vitamins to pigs from weaning to 100 lb. weight. They
report a 27 per cent increase in rate of gain (highly significant) from the use of
aureomycin. Ashton et al., [1955] fed aureomycin to pigs on various levels of
protein from 10 to 20 per cent. As the per cent of protein in the diet was increased
from 10 to 20 there was a decrease in back-fat depth and an increase in per cent of
lean cuts. They report that the pigs fed on a ration containing 20 per cent protein
resulted in carcasses with a significantly greater proportion of lean than those on
rations containing lower amounts of protein. Lassiter et al., [1955] compared
various levels of protein from 10 to 20 per cent for growing pigs and found that the
feed requirements per lb. of gain decreased somewhat when protein levels increased
to 16 per cent. Braude et al., [1953] in a review of literature on the use of antibiotics
in swine nutrition, report that in experiments conducted throughout the United
States, aureomycin increased the daily gain of growing swine about 35 per cent.
Davey et al., (1955) fed aureomycin at different rates to three generations of swine
and noted no adverse effect upon birth weight or weaning weights. Feeding at the
rate of 50 mgm. per lb. feed gave the highest daily gain. Hanson et al., (1955) found
that the addition of vitamin B 12 in the ration for pigs gave a highly significant
increase in the rate of gain. The addition of aureomycin produced an additional
significant increase in the rate of gain.
Most of the work done on the feeding of aureomycin to pigs has been with normal
or below normal levels of protein, with the main object to save expensive protein
supplement. In certain areas of India groundnut cake is cheaper than cereals
such as maize, wheat or barley. Agarwala and Sundaresan [1955] found that the
pigs on a ration containing 27 per cent protein (50 per cent groundnut cake, 10 per
cent maize, plus other ingredients) made cheaper gains than the pigs on a 16 per cent
ration (20 per cent groundnut cake, 40 per cent maize, plus other ingredients).
1 University of Illinois, College of Agriculture, U. S. A. On assignment to Allahabad Agricul-
tural Institute for research in animal nutrition.
2 . Member, Animal Husbandry Department Staff, Agricultural Institute, Allahabad, U.P.
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