124 PRINCIPLES OP FEEDING FARM ANIMALS 



must be made to the Wolff-Lehmann standards to adapt 

 them to American conditions. In practically every instance 

 the amount of dry substance prescribed is 10 to 20 per cent 

 too high. The protein prescribed is from 10 to 40 per cent 

 too high, the greatest difference being in the cases of fatten- 

 ing and working animals and, consequently, the nutritive 

 ratio is too narrow. This is due to the fact that the early 

 students of animal nutrition thought that fattening and work 

 were produced largely or entirely at the expense of the pro- 

 tein of the ration. This of course makes the Wolff-Lehmann 

 standard for these classes of animals less valuable. But 

 little attention should be given to the fat content of the 

 ration, it being considered satisfactory if the requirements 

 for protein and carbohydrates are fulfilled. 



Henry and Morrison ^ have recently suggested modifica- 

 tions of the Wolff-Lehmann standards for dairy cows, beef 

 cattle, horses, sheep, and hogs. These standards attempt 

 to correct the objections to the original Wolff-Lehmann 

 standards, and their use is recommended in preference to 

 the older standards. The Henry-Morrison standards are 

 given in Tal)le 33 of the Appendix. 



The Armsby Standard. — Perhaps the simplest and among 

 the most accurate standards for the maintenance, growth, 

 and fattening of cattle and sheep are those presented by 

 Armsby of the Pennsylvania Station. ^ A modification of 

 his standard for dairy cows is presented by Van Norman.^ 

 These standards are based principally upon the work of 

 Armsby in this country and upon that of Kellner in Germany. 

 They are given in Table 34 of the Appendix. 



1 "Feeds and Feeding," pp. 134 and 669. 



2 U. S. Dept. of Agr. Farmers' Bui. 346. 

 s Penn. Exp. Sta. Bui. 114. 



