328 
Journal of Agricultural Research 
Vol. XXI, No. s 
energy STORAGE 
14. Pigs whose sole source of protein was corn stored less therms on 
the average in proportion to the thermal value of the feeds consumed 
than did the pigs to whose ration protein from animal sources was added. 
15. From the standpoint of energy storage the small amounts of milk 
protein were as efficient as the larger amounts, but not more so. 
16. From the standpoint of energy storage the feeding of corn alone 
is not efficient. The addition of a small amount of protein from other 
sources from one-tenth to one-third of the total is as efficient as when 
one-half or more of the protein comes from other sources. 
IV. EFFECT OF PROLONGED FEEDING OF CORN ALONE, CORN AND 
ASH, OR CORN AND PROTEIN-FREE SKIM MILK ON THE GROWTH 
AND DEVELOPMENT OF PIGS 
That com alone, com and ash, or com and protein-free skim milk is 
deficient as a ration for young growing pigs has been shown in section III. 
In experiment II of the series of experiments from which these data have 
been taken, one of the pigs fed corn alone was continued on this feed for 
1,060 days, counting from the beginning of the experiment. This pig 
was 4 J 4 months old at the beginning of the trial, and weighed 54 pounds. 
In experiment III of this same series, one pig from the lot fed corn and ash 
and one from the lot fed corn and protein-free skim milk were continued 
on through for 900 days, counting from the beginning of the experiment. 
These two pigs were 3 y 2 months old at the beginning of the experiment. 
The pig fed corn and ash weighed 42 pounds and the pig fed corn and 
protein-free skim milk weighed 47 pounds at the beginning of the experi¬ 
ment. These ages and weights are important because if these pigs had 
been younger at the beginning of the trial the results might have been 
different. 
GAIN IN LIVE WEIGHT 
The live weight of these pigs at 100-day periods, the gain for these 
periods, and the corn consumed are given in Table XXI. 
The pig fed corn and ash did not make constant gains until 400 days 
after the beginning of the experiment. The total gain in the first 400 
days of the experiment was only 18 pounds, and this was all gained in 
the first 200 days. This net gain of 18 pounds was at the expense of con¬ 
suming 361.3 pounds of corn, or 20 pounds consumed for 1 pound of gain. 
During the last 523 days of the trial the gain was 334 pounds and the corn 
consumed was 1,646 pounds, or 1 pound gain for 5 pounds consumed. 
The period of greatest increase was from the seven hundredth to the 
nine hundredth day. In this time the consumption was 944 pounds and 
the gain 215 pounds, or 1 pound gain for 4.4 pounds consumed. 
