BREEDS OF SWINE 433 



20th and May 5th. The time will depend on the facilities for 

 housing the sows during farrowing time, and whether breeding or 

 market hogs are raised. 



If raising pure^breds for breeding purposes, the sows should be 

 bred so the pigs will be farrowed early, so they will be large enough 

 for service by the breeding season in the fall. 



In raising market hogs, they should be farrowed as early as 

 they can be kept warm and made to thrive. Thus with good care 

 they will be reaay for market before severe winter weather. 



During the mating season it is a good practice to place all the 

 breeding sows in a lot together, so that the period of heat may be 

 readily detected. It is a common practice on many farms to turn 

 the boar in with the sows and let him serve them at will. The 

 dangers from this method are that the sows may vary in size. If 

 some of the sows are large and the boar small, he will be unable to 

 serve the large ones and the small ones may suffer if the boar is 

 old and heavy. The other danger is the boar may misuse himself. 

 These dangers can be avoided by confining the boar in a lot adjoin- 

 ing the sow pen and turning the sows with him when in heat long 

 enough for a single service. In case the boar is unable to serve a 

 sow, it is well to use a breeding crate, which is designed to give him 

 an advantage. (N. D. Bui. 83.) 



Sows carry their pigs about 16 weeks, and usually will not take 

 the boar while suckling pigs, except immediately after the litter is 

 dropped, and they must be bred then or after the pigs are weaned. 

 The periods of heat are about sixteen days apart, altnough they vary 

 with the individual. (Wyo. B. 74.) 



Gilts should not be served before the age of 8 months, bringing 

 the first litter at 12 months. This gives sufficient time for the devel- 

 opment of the reproductive organs. (F. B. 205.) 



Castrating and Spaying. The 'boar pigs should be castrated 

 during cool weather, as soon as the testicles descend into the scrotum. 

 An early date is always preferable to a late one, for the development 

 of sex characteristics is of no value to an animal that is intended for 

 meat. 



The practice of spaying sows is not very general. It is much 

 more difficult than castration. It often happens that sows may 

 become pregnant before spaying and bear a good litter of pigs after 

 that operation. (F. B. 205.) 



The results of the experiment at the Utah Station show the 

 gains to have been slightly in favor of the unspayed sows, though 

 the difference is less than 5 per cent. This single test does not give 

 sufficient data from which to draw a conclusion, but it indicates that 

 there is practically no difference in the feeding qualities of spayed 

 and unspayed sows. (Utah B. 70.) 



Management of the Boar. As soon as the boar arrives, he 

 should be thoroughly dipped or washed with some of the coal tar 

 dips for destroying lice, and given the same treatment after ten 

 days. For three weeks after arrival he should be kept at a safe dis- 



