312 
Journal of Agricultural Research 
Vol. XXI, No. s 
and most of the ash from the milk. The quantity obtained from 3 
pounds of milk was fed for each pound of com. These two pigs 
were continued on these rations until they were nearly 3 years old. 
Figures on the feed and growth of the eight pigs, showing the ratio of the 
protein stored to the protein consumed, are given in Table VIII. 
The average ratio of the protein stored to the protein consumed for all 
these pigs is 1 to 7.5. As corn was practically the sole source of protein 
for all these pigs it means that when they are fed corn alone pigs will store 
1 pound of protein for about 7.5 pounds consumed. This is a wide ratio. 
It is not so much that the protein in corn occurs in too small a proportion 
but that a large part of this protein is deficient in lysin and tryptophane. 
These occur in too small proportions in relation to the amount of other 
substances which can be used only for the production of fat. 
The fact that the two pigs fed until nearly 3 years old on a deficient 
ration stored protein in the same ratio as the younger pigs should be 
noted. The fact that these pigs did not grow for over a year at the 
beginning of the trial means that there was a period in the life of these 
two pigs when the storage of protein in relation to the amount consumed 
was much less than the average ratio for the whole life period; and ac¬ 
cordingly there must have been a time when the storage of protein took 
place in a much narrower ratio. The development of these two pigs will 
be studied in a subsequent section of this paper. 
PROTEIN STORED FROM CORN SUPPLEMENTED WITH A SMALL AMOUNT 
OF PROTEIN FROM MILK 
The two proteins in milk, casein and albumin, contain the two amino * 
acids, lysin and tryptophane, both missing in zein. As milk is the 
natural food for young mammals, it is expected that the proteins in milk 
should contain the materials needed for growth. How much protein is 
needed from milk in order to supplement the protein in corn? Table 
IX gives the figures on the feed and growth of three pigs fed small 
amounts of supplementary milk protein and shows the ratios of protein 
stored to protein consumed. 
Table IX .—Relation of protein stored to protein consumed 
Experi¬ 
ment No. 
Ration. 
Protein 
stored. 
Protein consumed. 
Ratio. 
From 
corn. 
From 
milk. 
Pounds. 
Pounds. 
Pounds. 
IV 
Com and milk albumin. 
14 . 14 
59. OO 
6. 71 
1:4.65 
IV. 
Corn and milk protein every seventh 
day. 
is- 71 
66. 60 
8. OO 
1:4.75 
V. 
Corn and casein every seventh day... 
10.26 
55 - 16 
5.61 
i- 5 - 93 
