460 Journal of Agricultural Research voi. iv, no. s 



nation by this path in lambs after subcutaneous injection of either 

 inorganic phosphates or glycerophosphates. However, the observa- 

 tions of Le Clerc and Cook ^ on rabbits seem to form an exception to 

 this general rule. 



The utilization and final fate of phosphorus compounds is probably 

 in part determined by the amount and nature of the accompanying food 

 constituents. That the amount of phosphorus in the ration affects the 

 use made of protein by growing pigs is indicated by the work of Hart, 

 McCollum, and Fuller.^ Work done in this laboratory by Williams and 

 Emmett^ does not show a variation in the percentage or the distribution 

 of phosphorus in the bodies or the parts of the bodies of growing pigs 

 resulting from variations in the amount of protein consumed. 



DESCRIPTION OF THE METABOLISM EXPERIMENT 

 ANIMALS AND RATIONS USED 



Six high-grade Shropshire lambs were used in this experiment, which 

 was a metabolism test of 1 2 successive days. Two representative lambs 

 9 months old were chosen from each of three lots which had been fed from 

 the time of weaning, June 25, until this experiment began, December 23, 

 on the same feeds, though the proportions fed were different. The rations 

 of the three lots, both before and during the metabolism test, consisted of 

 alfalfa hay, shelled com, and old-process linseed meal. The quantity of 

 alfalfa hay depended upon the appetite of the individual. Until Decem- 

 ber 3 of the main feeding experiment there were fed 1.5 pounds of con- 

 centrates for each 100 pounds of live weight, after which time actual 

 increase of concentrates with the increase of live weight was deemed 

 unwise. The daily allowance of concentrates, then, remained constant 

 during the metabolism test. The concentrates of the ration for the low- 

 protein lot consisted of 95 per cent of shelled com and 5 per cent of 

 linseed meal; for the medium-protein lot the concentrates consisted 

 of 75 per cent of com and 25 per cent of linseed meal; and for the high- 

 protein lot they consisted of equal parts of com and linseed meal. Water 

 was accessible at all times. The amounts of feed and water consumed 

 were determined by the difference between the quantities offered and 

 those refused. 



CARE OF ANIMALS 



On December 17, 19 10, each lamb was put into a metabolism cage 

 which was large enough to allow the animal to turn around easily. To 

 each lamb was strapped a canvas bag in which the feces were collected. 



' Le Clerc, J. A., and Cook, F. C. Metabolism experiments with organic and inorganic phosphorus. 

 In Jour. Biol. Chem., v. 2, no. 3, p. 203-216. 1906. 



^ Hart, E. B., McCoUnm, E. V., and Fuller, J. G. The role of inorganic phosphorus in the nutrition 

 of animals. Wis. Agr. Exp. Sta. Research Bui. i, 38 p., 7 fig. 1909. 



8 Williams, R. H., and Emmett, A. D. A study of the phosphorus content of growing pigs with special 

 reference to the influence of the quantity of protein consumed. 111. Agr. Exp. Sta. Bui. 171, p. 205-230, 5 

 fig. 1914- 



