16 SWINE PRACTICE 



year depends entirely upon circumstances. A large percentage of 

 the breeders so arrange their schedule that two litters can be pro- 

 duced each year and thus apparently make the breeding business 

 much more profitable. The care of the brood sow is practically the 

 same as that of the boar, except that several sows may be main- 

 tained in the same enclosure during both winter and summer months, 

 or during the entire year, excepting the farrowing season and for 

 three or four weeks thereafter. 



The dates for farrowing should be carefully considered and will 

 necessarily vary according to whether the breeder is desirous of pro- 

 ducing two litters per year or one, and will depend on climate 

 and the housing facilities on the farm. In the middle west, where 

 two litters are produced annually, the majority of breeders favor 

 the dates between the middle of March and the middle of April for 

 the first litter and the middle of September to the middle of October 

 for the second litter. "When different dates than the above are 

 selected, particularly for the spring litter and especially in the 

 northern countries, the breeder must be certain that he has the facili- 

 ties for keeping the small pigs properly sheltered from inclement 

 weather. A few breeders will naturally select other dates than those 

 indicated and perhaps have goods reasons for so doing. 



When breeders have several sows, they usually prefer to have them 

 all farrow about the same time, to economize labor in the care of the 

 pigs. This, of course, is ordinarily advisable. The provision for 

 farrowing, particularly as to housing, is very important. Most suc- 

 cessful breeders now favor the individual hog house, and this is cer- 

 tainly profitable where surroundings and climatic conditions will 

 permit. As to the type of house, there is a variety of opinions but 

 if the house is so constructed that it will protect against inclement 

 weather and be so arranged that there is good drainage and that the 

 pigs can be protected from the sow crushing them, it will meet all of 

 the usual requirements. For early spring farrowing, some pure-bred 

 breeders have provided heated hog houses, containing several indi- 

 vidual pens without outside runs, which is of course a desirable 

 method but relatively expensive. The single farrowing house is 

 most desirable for grade breeding and particularly where a large 

 number of hogs are kept on the same farm every year. 



The period of estrum occurs in the sow every twenty-one days 

 until she conceives. The absence of the period of estrum is the first 

 indication of pregnancy. Sows usually begin to fill in the flank and 



