FEEDING STANDARDS CALCULATING RATIONS 123 



starch values. (78) The second column gives the digestible crude pro- 

 tein, as shown in Appendix Table III of this book, and the third column 

 the digestible true protein as estimated by Armsby from the crude protein 

 and Kellner's data. 



Of the feeds listed, rye has the highest net energy value, 93.71 therms 

 per 100 Ibs. Due to the large amount of fiber contained in the hulls, 

 the net energy value of oats is only 67.56 therms per 100 Ibs. The dry 

 roughages furnish much less net energy than the concentrates, wheat 

 straw having a value of only 7.22 therms per 100 Ibs. 



172. The Armsby standards for maintenance. The following table sets 

 forth the maintenance requirements of horses, cattle, sheep, and swine, as 

 presented by Armsby. 10 



Armsby 's maintenance requirements, per head daily 



The requirements for protein given in these tables depend on the live 

 weight. For example, the protein requirement for maintaining a 500-lb. 

 steer, neither gaining nor losing in weight, is 0.25 lb., and that for a 

 1,000-lb. steer just twice as much. As has been pointed out (90), theo- 

 retically the heat requirements for maintenance depend on body surface 

 instead of body weight, and Armsby hence computed the energy require- 

 ments on this basis. Therefore, he did not recommend twice as much net 

 energy for the 1,000-lb. steer as for the 500-lb. steer. However, he 

 found in later trials that the actual maintenance requirement of 

 different steers agreed as well with their live weights as with their body 

 surfaces. 



"The Nutrition of Farm Animals, pp. 711-714. 



