Management and Feeding in Winter 39 



FEEDING PREGNANT SOWS AND GILTS 



Two principal objects should be sought in the winter 

 feeding of sows due to farrow in the spring: first, com- 

 plete nourishment for the sows and their developing 

 pigs in embryo ; and second, economy. 



On the completeness of nourishment depend in large 

 part the general vigor and strength of the sows at farrow- 

 ing time, the development and strength of the pigs at 

 birth, and the capacity of the sows for milk secretion 

 after the pigs are born. Good feeding also requires that 

 the rations shall be cheap as well as balanced. The 

 cost of feeding sows during the pregnancy period repre- 

 sents an important item in the cost of the individual 

 pigs at birth, and the initial cost of the pigs is an impor- 

 tant factor in determining the cost of pork production. 



Demands. 



Before discussing specific feeds and rations, it will be 

 profitable to consider the physiological requirements 

 of the sows during this period. Mature sows, those 

 past two years of age, require food for two purposes : to 

 maintain and provide for the upkeep of their own bodies ; 

 and second, to supply the material for growing the embryo 

 pigs. Successful feeding of the mature sows during the 

 gestation period must provide the nourishment to satisfy 

 these two fundamental needs. 



The amount of feed required to meet the demands for 

 maintenance is constant. The requirements for the 

 growth of the embryo pigs, on the other hand, increase 

 more or less gradually with advancing pregnancy. Approx- 

 imately 75 per cent of the growth of the foetal litter takes 

 place in the last month of the gestation period. As preg- 



