Food Requirements of Animals. 257 



again. Consequently horses of different " action" will require 

 unlike amounts of food to accomplish the same task. 



When a horse exerts itself to the utmost the consumption of 

 oxygen rises rapidly and the food consumed per unit of work may 

 be nearly twice as much as with ordinary draft. A slow pace, 

 consistent with conditions involved, will be economical of food 

 consumption per unit of work performed. 



Zuntz found that the requirements for a horse, plowing 8 hours 

 a day, were 14.03 pounds of digestible nutrients. This is some- 

 what less than the requirement found in the German standards of 

 Wolff and Lehmann. According to these formulas, a 1000 pound 

 horse requires 11.4 pounds of digestible food daily for moderate 

 work, 13.6 pounds for average work, and 16.6 pounds for heavy 

 work. These standards also call for a nutritive ratio of 1 :7 to 

 1 :6, dependent upon the severity of the labor. On the other 

 hand, Lavalard, recommends that 1.15 pounds of digestible pro- 

 tein daily is sufficient for ordinary labor, and 1.35 pounds when 

 the labor is severe. This is a nutritive ratio not far from 1 :10. 

 From what has been said on the source of muscular force, it is 

 probable that the nutritive ratio recommended by the German 

 standard is narrower than need be. Horses working on the sugar 

 plantations of the Fiji islands receive 15 pounds of molasses per 

 day and a nutritive ratio of 1 :11.8. However, a fairly good pro- 

 portion of protein, for its peculiar and characteristic dynamic 

 effect, appears advisable. 



It is the opinion of Jordan that ' ' rations properly compounded 

 from ordinary farm products, such as silage, roots, meadow hay, 

 legume hays and the cereal grains, will generally contain protein 

 in sufficient proportion and will seldom need reinforcing with the 

 commercial nitrogenous feeding stuffs.'* 



If a horse at severe labor requires 16.6 pounds of digestible 

 nutrients, it is manifest that this could not be obtained from the 

 coarse fodders. Concentrated feeds must be used. Ten pounds 

 of hay is all a work horse should consume in one day. We have 

 seen that the productive value of the coarse feeds is not as large 



