diminishes. One of us* has previously called attention to the fact 

 that the protein supply called for by the current feeding standards for 

 growing cattle is greatly in excess of the sum of the maintenance re- 

 quirement and the amount actually stored up in the body, and thatwe 

 have no recorded determinations of the minimum protein demands 

 of such animals. The quantities of digestible protein consumed 

 by the two steers in this investigation, although less than those 

 called for by the standards, were still considerably in excess of the 

 amounts calculated in the publication referred to, but, on the other 

 hand, our results afford no proof that the minimum was reached. 

 Of course it must be regarded as probable that some waste of nitrog- 

 enous matter would be involved in the chemical reconstruction 

 necessary in changing food protein to body protein, while it 

 is not impossible that a certain surplus of protein may be necessary 

 for, or at least favorable to, growth. The tendency of recent investi- 

 gations, however, is to show that in all branches of feeding the 

 minimum protein requirement has been considerably exaggerated. 

 This has been shown to be true of the maintenance requirement and 

 of the requirement for milk production, while our results suggest 

 that it is also true for growth. At any rate this branch of the sub- 

 ject seems worthy of further investigation. 



* Armsby: U. S. Dept. of Agr., Bureau of Animal Industry, Bui. 108, pp. 

 27-29 and 57-65. 



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