3o8 Journal of Agricultural Research voi. xvi, no. 12 



hoped that their araino-acid make-up may be determined at some future 

 time. 



In this experiment we selected at random from 600 i -day-old incubator 

 chicks of the White Leghorn breed, three lots, each containing 60 chicks, 

 which were kept under identical conditions except that the diets were 

 different. The conditions governing these three lots of chicks were as 

 follows : 



lyOt I was placed in a large brooder house which opened on a large 

 grass run. The chicks were weighed individually on a torsion balance, 

 sensitive to o.i gm. the day after they were hatched and were so weighed 

 each succeeding week. The weekly individual weighings and mortality 

 records were kept, the previous weight records of all chicks which had 

 died being discarded, so that at the end of 28 weeks the weight records 

 represented only those that were living at that time. No particular care 

 was taken of these chicks except to see that they were properly watered, 

 fed, and housed. They were fed a ration consisting of equal parts of 

 finely ground soybeans, wheat, wheat bran, sunflower seed, and hemp- 

 seed. This was fed as a dry mash and was kept before them at all 

 times; and once a day, at noon, a wet mash of this mixture made with 

 sour skim milk was fed. Once a day a coarsely ground grain mixture, 

 consisting of equal parts of wheat, soybeans, hempseed, and cracked com, 

 was thrown into the litter in order to make them exercise by scratching 

 for it. Oyster shell, grit, and charcoal were before them at all times, 

 while sprouted oats and shredded cabbage leaves were liberally fed once 

 a day. It may be of interest to note that this ration is in every way 

 identical, with the exception that soybeans were added in an equal 

 quantity, with the ration fed to lot 3 of our previous paper,^ in which the 

 growth and general physical condition were normal, even though the 

 experiment was conducted under laboratory conditions. 



These chicks were closely watched, and any change in their physical 

 condition and habits was noted. When the treading period began, the 

 cockerels and pullets were separated to avoid any loss of weight occa- 

 sioned by undue exercise. 



Lot 2 was kept under the same conditions, only this lot could not be 

 separated into cockerels and pullets, because their external sexual char- 

 acteristics were depressed to such an extent that they could not be dis- 

 tinguished, and treading did not occur. A dry mash, which was kept 

 before them at all times, consisted of equal parts of finely ground barley, 

 rice, hominy, and oats, to which was added enough gluten flour and 

 butter fat to raise the protein and fat content of this grain mixture up to 

 that of the grain mixture fed as a mash to lot i. Once a day they 

 received a wet mash made of this grain mixture moistened with protein- 

 free milk. The grain ration fed in the litter consisted of equal parts of 



• BucKNER, G. D., NonAu, E. H., and Kastlb, J. H. 1915. op. cit. 



