64 HIGGLE SWINE BOOK. 



of food and a waste of money. The term nutritive 

 ratio is used to express the proper proportion. 



In the German tables here given the nutritive ratio 

 will be found simply by dividing the amount of pro- 

 tein into the amount of carbohydrates and fat, as the 

 carbohydrates and fat are not stated separately, as is 

 usually the case. The nutritive ratio in the case of 

 pigs two to three months old, in the German tables, 

 is about as one to four, and would be written i 14. 

 In the case of pigs three to five months old it is just 

 1:5. In the case of pigs eight to twelve months old it 

 is one to six and one-half, and would be written i : 6.5. 



This all means that the proportion of nitrogenous 

 food (protein) should rapidly decrease as the pig 

 grows older. At first a large proportion of protein is 

 needed for building up the frame-work and the mus- 

 cles, but later the food should be more of the nature 

 of sugar and starch (carbohydrates), with less protein. 

 Expressed in other words, the young pig needs milk, 

 wheat middlings and clover, while the adult needs corn. 



In tables where the carbohydrates and fat are given 

 in separate columns it is necessary to multiply the fat 

 by 2#, add to carbohydrates, and divide by protein. 

 This is because fat is 2# times as potent as starch and 

 sugar in heat-making and fat-producing effects. 



That is the whole story about nutritive ratio. It is 

 simple enough. And yet nothing in the whole science 

 of feeding live stock is more important than a just 

 comprehension of food effects upon the animal system. 



Yet I must frankly say that while the theory of 

 nutritive ratio is simple enough, we are still a long 

 distance away from exact and final knowledge in the 



