80 SWINE DISEASES 



TRACHEA 



Malformations 



A case occurs occasionally in which the esophagus 

 forms a union with the trachea. Pigs so affected usually 

 die soon after farrowing. 



Stenosis 



Congenital stenosis may occur in swine, but is rela- 

 tively rare. Acquired stenosis is also rare, because of 

 the protection of the trachea from external injuries. 



Tracheitis 



This inflammatory disturbance is usually associated 

 with laryngitis or bronchitis, and partakes so closely of 

 the nature of these latter affections that further descrip- 

 tion will not be given. 



Tumors 



Tracheal tumors are not common in swine, though 

 fibromas and myxomas of the benign tumors have been 

 observed. 



BRONCHIAL TUBES 



The principal malformations of the bronchial tubes 

 consists of an irregularity in the distribution of the 

 branches of those tubes, but as a rule this produces little 

 or no inconvenience to the animal and is therefore of 

 scientific interest only. 



Stenosis 



Bronchial stenosis is relatively common in swine. 

 The condition may affect either the large or small tubes. 

 Bronchial stenosis is probably most frequently the result 

 of a diseased condition of the bronchial mucosa, such as 

 catarrhal inflammation, ulceration, tuberculosis, para- 

 sitic invasion, or mechanical injury due to some foreign 

 body, as a needle or a nail. 



