54 Pork Production 



grass, tame pastures, clover, and alfalfa, as the weather 

 and other conditions make possible. The use of corn 

 silage, clover, and alfalfa silage, and pea-cannery waste 

 has been favorably reported on for pregnant sows when 

 the feeds were of good quality. When fed with care and 

 with the main purpose of supplying succulence, they may 

 be used in limited amounts with safety. Corn silage 

 is so bulky, however, as practically to exclude it from 

 the list of hog-feeds. As a rule, such provisions for the 

 breeding herd will mean more exercise, cheaper cost of 

 maintenance, and a more vigorous condition of health. 

 The necessity of feeding salt to hogs has not been 

 clearly established, but it is the belief of the best hog- 

 men that it is beneficial, especially for sows in pig. When 

 the sows are given the opportunity to eat salt at will, 

 they do not take more, apparently, than their systems 

 need. To make certain that the needs of the sows for 

 other minerals are also satisfied, it is a good practice 

 to give them constant access to a self-feeder containing 

 a mixture of the mineral elements most frequently lack- 

 ing in the ration. A combination of 12 parts charcoal, 

 3 parts of air-slacked lime, ground bone, or ground rocTc 

 phosphate, and 1 part common salt will be eaten with 

 relish and apparent benefit. The addition of wood- 

 ashes in the same quantity as the lime would probably 

 improve the combination. 



Conclusions. 



Summarizing the foregoing, the following fundamental 

 facts may be set down as practical guides in compound- 

 ing rations for pregnant sows : 



First, Every ration must be balanced; i.e., should 

 contain more muscle and bone-forming material than is 



