296 The Feeding of Animals 



the urine and in time protein starvation will cause 

 death. 



Any ration fed for production may be looked upon 

 as made up of two parts, that which is needed to main- 

 tain the animal and that which may be applied to 

 growth or the formation of milk solids. It is possible, 

 of course, for the production of milk or wool to occur 

 when the cow or sheep is fed what is really only a 

 maintenance ration, but the materials for production 

 under these circumstances are furnished at the expense 

 of the body substance. With what is regarded as liberal 

 feeding, from one -third to one -half of a production 

 ration is needed for maintenance purposes. It seems 

 fitting, then, to speak of a maintenance ration as a fun- 

 damental quantity, a knowledge of which is important 

 to both science and practice. It is clear that no rational 

 understanding of the uses of food can be had unless we 

 know what amount is required simply for maintenance, 

 and the feeder is certainly helped to a more intelligent 

 compounding of rations if he has some means of judg- 

 ing how large an excess he is supplying for production 

 purposes. Occasionally, too, it is desired to provide 

 horses and other animals when not at work with just 

 enough food to keep them in a uniform condition with- 

 out gain or loss. 



No ration is more easily provided from the ordinary 

 farm supply than is that for maintenance, for two 

 reasons: (1) because the quantity of available nutrients 

 which must be eaten is so small that this ration may 

 be wholly or mostly made up of bulky materials such 

 as corn fodder and hay; (2) because investigation has 



