298 
Journal of Agricultural Research 
Vol, XXI, No. 5 
of digestible protein per day per 100 pounds live weight for the three 
lots were, respectively, 0.32 pound, 0.70 pound, and 0.94 pound. 
The weights of the kidneys of the pigs of the low protein lot were about 50 per cent 
lower than those of the pigs of the medium and high protein lots. The data for the 
other urinary organs and for the organs of the central nervous system did not show 
any lot differences that seemed significant. . . . The weights of the heart, liver, 
spleen, pancreas, gall bladder, and lungs of the pigs from the three lots varied more 
or less directly with the live weight of the animals. 
Carroll and Emmett ( 1 ) report investigations on 21 lambs, divided into 
three lots, fed on (1) low, (2) medium, and (3) high protein planes. 
Slaughter tests showed that with the exception of the kidneys, the feed has little 
or no effect on the development of the brain, kidneys, liver, and heart. The kidneys 
seemed to increase directly with the protein feed. Individuality seems to be a very 
great factor, in fact, greater than the feed. 
Forbes ( 3 ) notes that with pigs fed com alone the liver, kidneys, 
lungs, and heart all compose an abnormally small proportion of the 
increase and the fat composes an abnormally large proportion of the 
increase. Sanborn ( 8 , 9, 10 ) concludes from his investigations that the 
corn-fed hogs had a less abundant coat of hair, smaller spleen, liver, and 
kidneys, and smaller bones. Henry (< 5 ) found that the corn-fed hogs 
had an abnormally small amount of hair and a thin skin. The spleen, 
liver, and kidneys were unusually small, while the brain, heart, and 
lungs were not affected. 
The slaughter tests made on the pigs fed the various rations, the 
results of which are recorded in Table VI, furnished abundant material 
for the study of the effect of these rations on the development of the 
internal organs—heart, lungs, liver, and kidneys. At the time of 
slaughter, these organs were weighed as soon as removed from the body 
on a scale accurate to 0.01 pound. The accuracy of the weights depends, 
of course, on the uniformity in separating these organs from their sup¬ 
porting tissues at relatively the same place. This involves considerable 
error, as is well known to all who are familiar with this class of work. 
Just how large this error is can not be determined. If a large number of 
tests were made on similar pigs, these variations would be eliminated 
in the average. 
The figures as obtained are given in Table VI, and they are arranged 
in order of increasing weights. A study of these figures will show that, 
on the whole, these organs increase in weight as the body increases in 
weight, but not in the same proportion. The smaller pigs have relatively 
larger organs. This is due to the increase in fat in the larger pigs. The 
increase in fat takes place faster than the increase in any other con¬ 
stituent or parts of the body. But even allowing for this, the larger pigs 
do not uniformly have larger organs than smaller pigs. Thus, variations 
can not be correlated with the different rations fed and must be due to 
the individuality of the animals. From the results of the analysis of the 
