46 SWINE DISEASES 



appear dejected and dull, having an arched back and an 

 indisposition to move. 



Treatment. If possible, remove the cause. Give 

 proper diet to the sow and have clean, wholesome sur- 

 roundings for the pigs. Medicinal treatment of the 

 affected pigs, particularly those depending entirely upon 

 their mother's milk, is difficult. It is a good practice 

 to hasten the removal of the irritating substances from 

 the bowel, by the use of castor oil or similar purga- 

 tive. If the diarrhea persists after the correction of 

 diet and the action of castor oil, small quantities of 

 bismuth subnitrate may be used to advantage. Intes- 

 tinal antiseptics, such as salol and the sulphocarbolates 

 of sodium, calcium, and zinc, are exceedingly beneficial 

 where they can be administered frequently. 



Parasites 



The intestine of swine is a common abode for para- 

 sites. Parasitic infestation is most prevalent in young 

 animals, but because of the mode of eating and the 

 habits of swine it is rather the exception to find even 

 an old hog entirely free from intestinal parasites. Their 

 injury to the host depends upon the kind and the number 

 of parasites. Intestinal parasites injure swine as follows: 



1. Abstraction of nutrition. 



2. Obstruction. 



(a) Of the lumen of the intestine. 



(b) Of the lumen of the hepatic duct. 



3. Irritation of mucous membrane due to movement. 



4. Irritation of mucous membrane due to lip attach- 

 ment resulting in inflammation, necrosis, and ulceration. 



5. Liberation of chemical substances that produce 

 nervous irritation or hematolysis. 



The following parasites infest the intestine of swine: 



1. Ascaris suum. 



2. Esophagostoma dentatum. 



3. Trichocephalus crenatus. 



4. Trichinella spiralis. 



5. Gigantorhynchus hirudinaceus. 



