ABSTRACTS
81
ranged from 83 to 90 days with an average of 86 and a standard deviation of 5. The
seventh group of 20 steer calves maintained on a ration containing 12.5 per cent cotton
seed meal, 25 per cent sorghum grain, 62.5 per cent cotton seed hulls, limestone flour
and salt ad lib. developed night blindness within a period varying from 65 to 131 days
with an average of 79 and a standard deviation of 17. The 8th group of 12 steer calves
were on a ration containing 15 per cent cotton seed meal, 28 per cent sorghum grain, 57
per cent sorghum fodder, limestone flour and salt ad lib. The depletion time ranged
from 46 to 61 days with an average of 56 and a standard deviation of 6.
Carotene content per gm. of the grain varied from 0.3 µg.-0.5 fig. and of the sor-
ghum fodder per gm. approximated to 4 µg. The animals of the seventh group were fed
on sorghum fodder containing 2 µg. of carotene per gm. for the first 58 days and cotton
seed hulls thereafter.
The effect of significant amount of carotene in alfalfa leaf meal which supplied
1000 µg. of carotene per 100 lb. live-weight of another group of ten heifer calves daily
was the lengthening of average depletion time of 96 days by 15 more days.
It is concluded, therefore, that the influence of age and the nature of previous food
supply is most significant in the depletion of vitamin A reserve of range cattle.
[B. C. R. S.]
Values of various protein feeds for growing chicks. R. M. SHERWOOD and
J. R. COUCH (1940). Texas. Agri. Exp. Sta. Bull. No. 588, pp.
1-20 (16 refs.).
I N a series of six experiments vacuum dried fish meal was fed to chicks as it was found
that it had a higher biological value and contained higher amounts of vitamins A and
G than those of fish meals prepared at high temperatures. In these particular experi-
ments fish meal gave better growth results when fed along with soyabean oil meal and
cotton seed meal than meat and bone scraps. Fish meal also proved superior to meat
and bone scraps when used as a supplement along with peanut meal and cotton seed
meal or soyabean oil meal. In addition to better growth fish meal also gave more econo-
mical food consumption per unit of gain in weight. A supplement of 3 parts of fish meal
and 3 parts of meat and bone scraps gave better results than 6 parts of meat and bone
scraps but poorer results than 6 parts of fish meal. These experiments are however
somewhat open to criticism as no effort was made to feed equal levels of protein but these
variations do not appear sufficiently great to produce such wide differences in the growth
results.
In other comparisons chicks fed on supplements of fish meal, meat and bone scraps
and soyabean oil meal grew faster and made more economical food utilization than chicks
fed on meat and bone scraps, cotton seed meal and soyabean oil meal. Supplements of
fish meal, meat and bone scraps and cotton seed meal gave better results than supple-
ments of meat and bone scraps, cotton seed meal and soyabean oil meal.
Chicks fed on liver meal as a protein supplement made lower gains in weight and
consumed more food per unit of grain than chicks fed on fish meal supplements.
In other experiments chicks fed on supplements of cotton seed meal, soyabean oil
meal and fish meal or meat and bone scraps made more rapid gains in weight than those
fed on peanut meal, soyabean oil meal and fish meal or meat and bone scraps. Suppl-
ements of peanut meal gave poorer growth results than soyabean oil meal.
In two experiments a protein supplement containing 1/3 part soyabean oil meal
gave no better results than similar protein supplements containing 1/3 part cotton seed
meal. Further data indicated that in a mixed protein supplement the substitution of
part of the soyabean oil meal supplement with linseed oil meal resulted in a lowering of
the growth rate. In mixed protein supplements there was no indication of any advant-
age in a partial replacement of cotton seed meal with linseed oil meal.
In another series of experiments to test out the adequacy of the rations for vitamin
G it was found that supplements of fish meal, cotton seed meal and soyabean oil meal
and alfalfa leaf meal were not improved by the addition of various proportions of dried
whey. In another experiment where the fish meal was replaced by meat and bone scraps,
the addition of 1 per cent dried whey improved the rate of growth
[A. J. M.]