June i, 1921 
Effect of Ration on the Development of Pigs 
33i 
days the gain was 461 pounds and the corn consumed was 2,141 pounds, 
or 1 pound of gain for 4.6 pounds consumed. In the last period of his 
life the pig fed com alone made as good gains as the pig fed corn and ash 
or com and protein-free skim milk. The facts presented above are 
graphically shown in figure 19. 
The outstanding fact is that in all these pigs there was a long period 
in which the gains were very small, and after this period the rate of gain 
and the gain for the amount consumed was equal to that of pigs fed a 
standard ration. It evidently means that before a pig can make satis¬ 
factory gains it must attain a certain development. When corn alone is 
the sole diet this development is attained very slowly. When alfalfa 
pasture was the sole source of food, this development took place more 
rapidly, although the pigs did not gain much in weight. This fact was 
illustrated by some pigs in this series of experiments which were fed on 
alfalfa pasture alone. One lot of those pigs gained an average of only 
3 pounds each in 120 days. When they were put on corn alone they 
gained 67 pounds in as many days. This gain was produced from 284 
pounds of com, or 4X pounds of com for each pound of gain. One pig 
from this lot was analyzed when taken off the alfalfa pasture. Compared 
with a control pig killed at the beginning of the experiment, he had gained 
11.66 pounds moisture, 0.77 pound ash, 2.93 pounds protein, but lost 
14.84 pounds fat. Unfortunately no pig from this lot was slaughtered 
at the end of the trial. But, as has been shown in section I, it is safe to 
compare pigs of approximately equal size for the purpose of calculating 
chemical composition. A comparison of the pig of this lot fed com alone 
after alfalfa pasture with a slaughtered pig fed com alone, showed that 
the following average pounds of gain were made on com alone in 67 days: 
moisture, 11.73; ash, 0.87; protein, 3.88; fat, 56.71. While the gains on 
alfalfa pasture were unsatisfactory, the pigs had attained a certain devel¬ 
opment of body which gave them vigor to make rapid gains when put on 
com alone. It should be noted that the gains were comparatively 
large in protein and ash on alfalfa pasture, and on com alone the gain 
was largely fat. Alfalfa alone is strong in those growth-producing 
properties in which com is weak. Com is strong in fat-producing 
properties in which alfalfa is weak. Hughes ( 6 ) has shown that when 
chickens are fed on com alone, the growth curve is similar to the one made 
by pigs fed on com alone. He also shows that the rate of growth in 
chickens can be increased by forced feeding. 
nutrients and therms in corn consumed 
♦ 
The average composition of com fed these pigs was assumed to be the 
same as the average of the corn used in all these experiments—namely, 
protein, 9.65 per cent; carbohydrates, 75 per cent; fat, 3.8 per cent. In 
