226 SWINJE PRACTICE 



indirectly responsible for extensive losses of pigs, particularly on 

 farms where swine have been maintained for many years. This 

 condition is more prevalent than is ordinarily suspected because the 

 majority of swine breeders rarely report the loss of a little pig and 

 they usually assume that such losses are unavoidable. Stomatitis 

 is much more prevalent in pigs that are farrowed and kept in insani- 

 tary pens and surroundings than in pigs farrowed and maintained 

 in ckan quarters and sanitary surroundings. After the disease has 

 once occurred in pigs on a given farm it is prone to recur in the 

 pigs farrowed on the same premises thereafter. 



Etiology. — Stomatitis in pigs is probably due to a variety of causes. 

 Insanitary surroundings, improper housing and feed are important 

 predisposing factors. The condition probably occurs most frequently 

 in pigs in large litters because they are likely to be under-nourished 

 and are prone to injure each other while attempting to nurse. Any 

 abrasion will provide an avenue of entrance for various infecting 

 microorganisms. 



The following bacteria have been isolated from the lesions of stoma-' 

 titis in suckling pigs: pyogenic micrococci, steptococci, B. pyo- 

 cyaneus, B. necrophorus, -B. coli communis and others. Practically 

 pure cultures of any one of the foregoing microorganisms have been 

 obtained from different cases of this condition. The B. pyocyaneus 

 and B. necrophorus are more destructive than the. pyogenic cocci or 

 the colon bacillus. These infective microorganisms are practically 

 universally distributed but probably are not capable of invading 

 tissue unless they have been injured or damaged. "When one pig in 

 a litter becomes infected the infecting microbian agent is trans- 

 ferred to the sow's teat and other pigs become infected. 



Lesions. — The lesions are as variable as the etiologic factors and 

 are probably largely determined by the infecting agent. The lesions 

 may occur on the lips, snout, or any portion of the mucous mem- 

 brane of the mouth or tongue. The lesion associated with pyogenic 

 cocci is first a hyperemic or hemorrhagic tumefied area that has a 

 tendency to form a pustule; more rarely diffuse surface suppuration 

 succeeds the hyperemic stage. The pus in these cases is dirty white 

 or tinged with yellow. The lesion is usually quite superficial, al- 

 though cases have been observed in which the submucosa or sub- 

 subcutis was undetermined for some distance. 



The B. pyocyaneus produces a more extensive lesion than the pyo- 

 genic cocci. The progress of the disease is rapid and tissue destruc- 



