434 



NUTRITION OF FARM ANIMALS 



stimulated by the protein supply in the feed. It is of the high- 

 est- economic importance, therefore, to utilize to the full the 

 ability of the young animal to lay on protein tissue. In the early 

 stages of growth, he is able to utilize a relatively abundant supply 

 of feed protein which, if given to an older animal, would largely 

 undergo protein katabolism and be lost so far as growth is 

 concerned, while at the same time the total feed per head re- 

 quired for maintenance is smaller. The feeder cannot afford 

 to stint the protein supply of the young animal, while the 

 earlier the process of growth can be completed or approach 

 nearly enough to completion to satisfy market demands, the 

 more economically will it be conducted. 



The conclusions regarding the rate of increase of protein 

 tissue considered in Chapter XI are, however, derived chiefly 

 from determinations of the gain or loss of total nitrogenous 

 matter, including, besides the edible portion, the protein of the 

 skin, hair, hoofs, horns and other epidermal tissue, of the in- 

 ternal organs and of the skeleton. It is important, therefore, 

 to inquire into the rate of increase of the edible portion of the 

 carcass. 



TABLE 112. GAIN OF FAT-FREE LEAN MEAT AND TOTAL PROTEIN BY 



LAMBS 



While it may be fairly assumed that the increase of edible meat 

 will be in a general way proportional to the increase of total protein, 

 it is equally clear that there may be considerable departures from 

 the average. Unfortunately, however, the data upon this point are 



