CHAPTER XXXVI 

 Rational Feeding of Animals 



467. Balanced Rations. A balanced ration is one 

 which contains a sufficient amount of nutrients from a 

 variety of foods to meet the requirements of the animal. 

 Since the different classes of nutrients serve different pur- 

 poses in the body, it is the object of rational feeding to 

 combine foods so as to supply the nutrients in the right 

 proportion for growth and work or production of milk, 

 meat or wool. Rational feeding is based upon (i) the 

 food requirements of animals, and (2) the amount of di- 

 gestible nutrients in foods. The food requirements of 

 animals are determined by experiments. 



468. A flaintenance Ration is one which furnishes all 

 of the nutrients required for maintaining the weight of 

 the body and for performing all of its functions without 

 allowing any nutrients for growth, work or other pur- 

 poses. A maintenance ration simply sustains the animal 

 without making allowance for growth or work. When 

 an animal is fed a maintenance ration, it neither gains nor 

 loses in weight ; an equilibrium is established between 

 the income and outgo of the food. The nitrogen in 

 the proteids of the food consumed is all returned in 

 the various waste products of the body. The element 

 nitrogen is taken as the index for determining the main- 

 tenance requirements of animals. When the nitrogen in 

 the waste products equals that in the food consumed, and 

 no work has been performed, a maintenance ration has 



