252 Agricultural Chemistry. 



but remains in the intestine. There it is converted into soaps, 

 composed of part of the fat and an alkali, and as such eliminated 

 from the body in the excreta. This excretion of soap entails to 

 the body a heavy loss of alkaline bases, which when continued for 

 some time results in disturbed nutrition. On an exclusive milk 

 diet containing 3.5 per cent of fat the supply of alkaline bases i? 

 only sufficient for normal development and the production of fat- 

 rich milk in cows is not attended by a corresponding increase in 

 the ash forming materials. Rich milk is the result of breeding 

 by man and is not a condition original to the milk of the cow. 



Another important fact to bear in mind is that the capacity to 

 digest the starchy grains and similar substances is somewhat un- 

 developed in the very young animal and that the ferments neces- 

 sary for this purpose are probably not yet very abundant. For 

 this reason the first substitute for milk should not consist too 

 largely of cereal grains, or concoctions of insoluble, starchy ma- 

 terials. Bulky, fibrous food is likewise unsuitable for the young 

 animal. The digestive tract of calves and colts must gradually 

 expand before the coarse hays can form a large part of their ra- 

 tion. 



Influence of food. In experiments on the influence of food 

 upon the development of the animal body, some interesting results 

 have been recorded. Sanborn and Henry fed to swine rations 

 varying considerably in the protein and ash supply. Comparisons 

 of middlings and blood against corn meal alone, or shorts and bran 

 against potatoes, tallow and corn meal, showed considerable dif- 

 ferences in the development of the animal. Those fed high nitro- 

 genous rations contained more blood than the others, while such 

 organs as the kidney and liver were larger in proportion to the 

 weight of the body, the bones stronger, and the proportion of 

 muscle greater. These were extreme rations, and not likely to 

 occur in practice, but the experiment serves the purpose of em- 

 phasizing the necessity of an abundant supply of protein and ash 

 material for the growing young. Swine fed on corn and gluten 

 feed, against corn, gluten feed and "floats" have shown marked 



