DISEASES OF -^HE GENERATIVE ORGANS 69 



ings in the pen, or crowding one another in going 

 through gates, doof-s, etc., may also cause it. .Other 

 accidental injuries and conditions that sometimes 

 cause abortion are kicks and blows in the region of 

 the abdomen, becoming excited by other animals, such 

 as dogs, sows in heat, etc., sudden falls, chilling, 

 spoiled food, food containing, ergot, digestive dis- 

 orders, hog cholera, swine plague, and other diseases. 



Infectious abortion in sows is not very well under- 

 stood. It is not a common disease, and although the 

 specific cause has not been discovered, this form of 

 abortion is no doubt due to a specific germ. The 

 conditions for spreading the infection from one herd 

 to another are not so favorable as in some classes of 

 farm animals, hence the disease does not spread 

 rapidly. 



Symptoms. — In abortion the parts are not pre- 

 pared for giving birth to the young, and the act may 

 be accompanied by marked nervous disturbances and 

 pain. Birth- may progress more slowly than when 

 the conditions are normal: However, the symptoms 

 depend largely on the period of pregnancy in which 

 the accident occurs and its cause. When caused by 

 an injury, the symptoms are more serious than when 

 due to a specific cause (germs). In the latter period 

 of pregnancy an accidental abortion is usually ac- 

 companied by a serious train of symptoms. 



The sow acts uneasy, is sick, and refuses to eat. 

 Abdominal pains may occur. The final symptoms are 

 trembling of the muscles, or shivering, more or less 

 straining, depression, and in some cases severe labor 



