HOW TO PRODUCE FARM ANIMALS 



209 



Sometimes the combination in the ration is expressed by 

 merely indicating the ratio between the amount of protein 

 and total carbohydrates (the latter including fats reduced to 

 terms of carbohydrates). Such ratios are called nutritive 

 ratios. They are expressed in this way: The first figure is 

 always i ; the second is the quotient obtained by dividing 

 the total amount of carbohydrates by the amount of protein. 



Graph showing returns from cattle and hogs per 

 $100 worth of feed used on farms of various sizes. 

 Cattle. Hogs. 



(Figures from Missouri Agricultural Experiment Station.) 



Thus if the ration contains three pounds of protein and 

 twenty-one pounds of carbohydrates, the nutritive ratio is 

 1:7. 



Although the nutritive ratio shows the desirable proportion 

 between protein and carbohydrates, it does not indicate the 

 amounts of each. A standard ration obviates this difficulty 

 by giving the estimated amount of protein and of carbo- 

 hydrates needed for each 1000 pounds of animal weight. 

 Some of the standard rations will be found in the appendix. 



