DISEASES OF ORGANS OF GENERATION 



By the organs of generation are meant those organs of the body 

 which are involved in the reproduction of the species. Among the 

 more important of these are the uterus, ovaries, vagina, and vulva 

 in the sow, and the scrotum, testicles, penis, and sheath in the male 

 animal. Diseases of these organs may be of an organic nature, in 

 which there is actual change in the structure of the organs, or it 

 may be merely functional, in which the interference is with the 

 normal work which these parts of the body are supposed to per- 

 form. 



STERE.ITY (BARRENNESS) 



Definition. — This is a condition in which the sow for some reason 

 is unable to become pregnant. The fault may be with the sow or 

 with the male animal, but, in either case, the result is the same, 

 conception faihng to occur after breeding. The condition may be 

 only a temporary one, due to some transient condition, or it may 

 be a permanent affair, and render the animal worthless for breed- 

 ing purposes. Barrenness is much more common in mares and 

 cows than in sows. 



Causes. — The causes of sterility are best considered under the 

 following heads : 



Causes in the Male. — Among those causes which may affect 

 the male animal, lack of or too frequent sexual intercourse are the 

 most important. If the male animal is not used reasonably often 

 for breeding, he becomes more or less unable to perform his func- 

 tion, and may entirely lose the power of impregnating the female. 

 On the other hand, if the boar is allowed to serve too large a num- 

 ber of sows the sexual organs become exhausted, and the animal is 

 unable to perform proper service. 



Old age is another important factor in determining impotency 

 in the male hog. As the animal gets old there is a tendency for 

 fat to collect in large amounts, and this may surround the testicle 



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