CHAPTEE XXXn. 



INTESTIGATIONS WITH SWDTB. 



823. Period of gestation. — According to Cobum, * young sows 

 carry their pigs from 100 to 106 days; old sows from 112 to 115 



days. 



Spencer,' writing of English pigs, says: *'The variations in 

 the time which a sow will carry her pigs are very slight, and these 

 are pretty well regulated by the age and condition of the sow; 

 thus, old and weakly sows and yelts (young sows) will most fre- 

 quently bring forth a day or two before the expiration of the six- 

 teen weeks. Sows in fair condition will generally farrow on the 

 one hundred and twelfth day, while strong and vigorous sows will 

 frequently go a few days over time." 



824. Weight of pigs at farrowing time. — A number of observa- 

 tions have been made by the writer at the Wisconsin Station » in 

 relation to the weight of piga at farrowing. The findings with 

 seven sows are reported below: 



Weights of pigs in order farrowed — Wisconsin Station. 



* Farrowed dead. 



The sows under study ranged in age from one to four years and 

 in weight from 240 to 577 pounds before farrowing. As the pigs 



* Swine Husbandry. 



» " Pigs, Breeds and Management.' 



» Rapt 1897. 



