2IO 



FOOD REQUIRED 



[chap. 



food gets utilised nor what proportion of it is stored 

 up within the animal. It is obvious that the animal 

 by no means adds to itself the whole of its food, or even 

 the whole of what it digests. We have already seen 

 that a considerable proportion of food is required simply 

 for maintenance, being burnt as fuel to keep up the 

 heat of the body and carry on the internal work of the 

 organs. But even if we make deductions of the matter 

 used for maintenance, we shall not find that the rest of 

 the digestible food is stored up in the body of the fatten- 

 ing animal. Lawes and Gilbert put together a large 

 number of statistics relating to animals being fattened 

 in the ordinary way upon the farm ; determining their 

 weight from time to time, and the weight and composi- 

 tion of the food which they had been receiving. From 

 these results Table XXII. was constructed, which shows 



Table XXII.— Relation of Food consumed to Live 

 Weight Increase. 



* Dry matter of solid excrement and urine, exclusive of litter. 



that to make i lb. of increase in the live weight of 

 oxen, 1 3 lb. of dry food material was necessary, while 

 about 9 lb. were wanted in the case of sheep and 



