FEEDING STANDARDSCALCULATING RATIONS 125 



174. Milk cows, fattening animals, and work horses. The require- 

 ments for milk cows, fattening animals, and work horses, according to 

 Armsby, are as follows: 



Milk production Add to maintenance requirement daily for each 

 pound of milk produced 



Fattening all species of animals with no considerable growth. Daily in 

 addition to the maintenance requirement 



Work horses, daily per 1,000 Ibs. live weight 



In computing rations for horses by the Armsby standard the net 

 energy values for horses, given in a later chapter (447), should be used 

 for the feeds for which such values are available. 



175. Fattening lambs. Bull and Emmett of the Illinois Station 11 have 

 made a critical and comprehensive study of the American investigations 

 in fattening lambs, covering trials in which 265 lots of lambs, aggregat- 

 ing 5.127 animals, were fed. From the results secured in these trials, 

 they give the following as the approximate minimum requirements of 

 digestible crude protein and net energy per 1,000 Ibs. live weight. 



"111. Bui. 166. 



