ANOMALIES AND DISEASES OP YOUNG PIGS 223 



trachea to the pharynx and are then swallowed, and those that are 

 not passed out with the feces develop to maturity in the small in- 

 testine. 



Lesions. — The lesion resulting from the invasion and development 

 of the larval ascarids in the lung is primarily an embolic pneumonia 

 with or without abscess formation. There is usually a marked serous 

 infiltration or edema of the pulmonary tissue. There may be hem- 

 orrhages of variable size. Microscopically larvae may be demon- 

 strated in the scrapings from the bronchial mucosa or from the 

 embolic pneumonic centers. 



Symptom. — Cough, nasal discharge, unthriftiness, and impaired 

 appetite are the usual symptoms manifested in an uncomplicated 

 case of' pulmonary ascaridiasis. These symptoms develop rapidly in 

 little pigs, and if the infestation has been extensive the pig usually 

 dies within four to seven days after the first manifested symptoms. 

 The symptoms evidenced in pigs that are six weeks old or older are 

 less intensive, and the majority of infested animals at this age re- 

 cover although they will show loss of condition and do not develop 

 properly. 



Treatment. — Thus far no medicinal treatment has been found that 

 is of value in overcoming this condition. Inhalations of medicated 

 vapors may be of some value in eliminating some of the larvae from 

 the bronchial tubes and trachea, particularly in the larger pigs. 

 However, the condition is easily prevented by the periodic adminis- 

 tration of santonin capsuks, thus eliminating the adults from the 

 breeding swine, and by the rigid enforcement of sanitary regulations. 

 It will be found that rotation of pastures and frequent changing of 

 quarters will be of great value in reducing the losses of pigs occa- 

 sioned by the larval form of the Ascaris suum. 



Infectious Rhinitis ("Bull-Nose or Sniffles") 



Infectious rhinitis is probably a specific infective disease of swine 

 characterized by inflammation of the mucous membrane of the nasal 

 chambers and related sinuses and by involvement and deformity of 

 the facial bones. This disease may be the same as infectious nasal 

 catarrh, excepting that it is more severe and destructive. 



This condition is rather prevalent and is responsible for the loss 

 of large numbers of pigs in various locations every year. The de- 

 velopment of "bull nose" has been observed in pigs that have been 

 kept in pens that have been used for swine for several consecutive 



