156 The Feeding of Animals 



pounds of digestible organic matter, giving thirty 

 pounds of milk containing 15 per cent of solids, 

 and neither gaining nor losing flesh, not far from 

 five pounds of this organic matter would be found 

 in the milk and urine, leaving about eleven pounds 

 to be used as fuel, about a pound and a half of 

 which might be derived from the protein and fat, 

 the remainder, or 9.5 pounds, consisting of carbo- 

 hydrates. If a fattening steer were eating the same 

 amount of the same kind of food and gaining two 

 pounds of live weight daily, the body increase and 

 urine would contain not over 2.5 pounds of dry 

 matter, leaving not less than 13.5 pounds to be oxi- 

 dized, of which twelve pounds might consist of car- 

 bohydrates and fat, mostly the former. It is clear, 

 then, that while other bodies serve as fuel, the carbo- 

 hydrates furnish much the larger part of that which 

 is needed for this use. 



Contrary to views that held for a time, it is now 

 well established that the animal fats may have their 

 source in the carbohydrates ; in other words, starch 

 and sugar and related bodies may serve the main 

 purpose in feeding animals for fattening. In many 

 experiments, notably those with swine, the protein 

 and fat of the food have fallen far short of ac- 

 counting for the fat in the body increase, some- 

 times much the greater part of the latter having 

 no possible source other than the carbohydrates. A 

 practical expression of this general conclusion con- 

 cerning the fat -forming function of carbohydrates is 

 seen in the well -recognized value of corn meal as a 



