STERILITY 679 



uterus. These cases are most often met with in old fat sows or as 

 a secondary result following inflammation of the womb. 



Inflammation of the womb is another most fruitful cause of 

 sterility. As a result of the catarrhal inflammation the womb 

 becomes coated on its inner surface with an acid mucous discharge, 

 which destroy the ova and semen before there is any chance for 

 conception to take place. In some cases there is an irritability of 

 the hning of the womb, and this organ immediately throws out the 

 semen and ova when they are brought together within its cavity. 

 In this way the male and female elements of conception are ex- 

 pelled before conception can take place. 



Sows which are in poor condition may be so run down as to be 

 incapable of producing a healthy ovum, or may even be so unsuited 

 for breeding purposes as to possess no sexual desire, and are, accord- 

 ingly, never in heat. These sows will not be served by the boar and, 

 accordingly, cannot become pregnant. The condition, however, is 

 only a temporary one in these cases, and is easily overcome by a 

 course of proper feeding and tonic medication. 



It is not unusual to meet with a case in which the opening into 

 the womb is closed, either temporarily by spasm of the muscles 

 of the vagina during the act of copulation, or it may be per- 

 manently as a result of contractions following an inflammation of 

 the vagina or womb. In some sows the uterus has never properly 

 developed, and is only a small rudimentary organ, entirely incap- 

 able of receiving the semen of the male. 



Poor feeding and lack of exercise may be another cause for 

 sterility in some cases. Old animals frequently breed poorly or 

 not at all. An attack of cholera may leave the sow barren, and 

 she may never be able to become pregnant again after an attack of 

 this disease. 



In those cases where any infection of the womb takes place after 

 farrowing the organ may remain in a swollen, boggy condition, and 

 it may be several months before it returns to normal condition 

 so as to be in shape to allow of the sow becoming pregnant. 



Diagnosis. — It is quite easy to determine whether it be the 

 male or the female that is at fault. If the boar is barren, all the 

 sows that he serves will fail to become pregnant. If, on the other 

 hand, the other sows in the herd become piggy and the suspected 



