OBSERVATION BY HAECKER 137 



40 pounds of 4 per cent, milk daily, the required 

 ration would be : 



Pro. C. H. Fat Pro. C. H. Fat 



(.0467 .214 .0159) x 40= 1.868 8.56 .636 

 (.07 .7 .01 )x8.5o= .595 5.95 .085 



Ration required, 2.463 14.51 .721 



A ration like this should be largely composed of 

 grain so that it will not contain so much bulk that 

 she will go off her feed, and yet furnish the nutri- 

 ents required. If a cow's ration is adjusted in bulk 

 with reference to her feeding capacity and in nutri- 

 ment content to the work she is doing, she will not 

 be overfed nor go off her feed. A cow will not do 

 her best unless she is so fed that she is satisfied, but 

 the ration should not contain more nutriment than 

 she actually needs. From this it follows that cows 

 do not require a uniform nutritive ratio in their ra- 

 tions, but that it varies according to the quantity of 

 milk yielded and weight of cow. 



To illustrate, let us take a cow weighing 1,200 

 pounds and yielding 20 pounds of milk daily, and 

 one weighing 850 pounds yielding 40 pounds of 

 milk, both testing 4 per cent. fat. 



Pro. C. H. Fat 



Nutrients for I Ib. of 4 per cent. milk.. .0467 .214 .0159 

 Nutrients for i cwt.. maintenance 07 .7 .01 



For cow weighing 1,200 pounds and yielding 20 

 pounds of 4 per cent, milk : 



Pro. C H. Fat 



Nutrients for 20 Ibs. milk 93 4.28 .32 



Nutrients for 12 cwt. maintenance... .84 8.40 .12 



Ration required 1.7712.68 .44 



Nutritive ratio 1-7-7 



