118 THE CHEMISTRY OP THE FA.RM. 



tion varying from 1 : 2'2 to 1 : 6'1, and in colostrum 

 the relation is still higher. In supplying very young 

 animals with artificial food the above facts must be 

 borne in mind ; the food should clearly be of an easily 

 digestible character, and contain a considerable propor- 

 tion of albuminoids and fat. Instead of this, foods rich in 

 starch are too often employed. Linseed is, of ordinary 

 foods, the one most similar to milk in composition. 



As the animal grows the quantity of food it requires 

 increases, at the same time a larger proportion of the food 

 is applied to the production of heat and mechanical work : 

 the proportion of nitrogenous matter in the food may 

 therefore gradually be diminished, carbo-hydrates and fat 

 being quite as fit as albuminoids for producing heat and 

 work. Under natural conditions this diminution in the 

 nitrogenous character of the diet soon takes place, the 

 animal daily taking more and more grass in addition to 

 its mother's milk. The albuminoid ratio of the diet of 

 young rapidly growing animals may vary from 1 : 5 to 

 1 : 7, the more nitrogenous diet being that most suitable 

 for younger animals, or for the production oc more rapid 

 increase. 



It is very important that the food supplied to young 

 animals should contain a sufficient amount of ash con- 

 stituents, and especially of lime : see p. 92. 



The Adult Animal. The food of an adult animal, 

 not fattening, is employed for the renovation of the 

 tissues, the formation of hair, wool, &c., and for the 

 production of heat and mechanical work; by far the 

 greater portion of the food is applied to the production 

 of heat. 



