246 



LIVESTOCK ON THE FARM 



BO far as protein and carbohydrates are concerned, by using 

 simply corn and soy beans or any other nitrogenous concen- 

 trate, the ration is better if it contains three or four feeds in- 

 stead of only two. Still more feeds is presumed to make the 

 ration still better. The greater the number of feeds in a ration 

 the greater will be the probability of supplying what the pig 

 needs. 



ETHER EXTRACT OR FAT 



Fat or ether extract is used, after it has been digested and 

 absorbed, for practically the same purposes as carbohydrate. 

 Nevertheless, to get the best results, it is necessary to supply 

 ether extract or fat in the ration to the extent that the animal 

 is able to take care of it. In a general way, a pig can use about 

 one-tenth as much of fat as it can of carbohydrate. 



Fig. 66. — Ether extract requirement of pigs. 



While all normal farm feeds for swine contain some fat, 

 rations in general do not contain enough of this substance. 

 The soy bean, which has already been mentioned in connection 

 with protein, is also rich in ether extract or fat, consequently 

 serves a double purpose in a ration. This being true, it is a 

 very valuable feed. If feeds are available for the control of 

 this part of the ration the above chart will serve as a guide. 



This curve has not as yet been so thoroughly established as 

 the others shown but is believed to be approximately correct. 



WATER 



About half of the weight of the body of a pig is water. 

 Water is used also in digestion and in metabolism. It has 

 been clearly shown that a given definite amount of water will 

 produce largest and most economical gains for marketing and 

 is best for breeding. It has further been shown that the 



