PRINCIPLES OF VETERINARY SURGERY 651 



PATHOLOGICAL REACTION.— The pathogenic 

 agent is non-pathogenic to the cavy, the dog, and the sheep 

 from subcutaneous injections. In the rabbit it is non-patho- 

 genic from subcutaneous or intraperitoneal injections. In 

 the hog it seems to produce the disease spontaneously from 

 subcutaneous inoculations of the face. 



SYMPTOMS. — (The disease often commences with 

 lameness, the result of multiple arthritis, attacking the com- 

 plicated articulations having wide articular surfaces, like 

 the femuro-tibio-patellar joint. The articular regions are 

 doughy, enlarged, painful and grow rickety. The articular 

 inflammation may diminish and completely disappear or 

 iiiay accentuate every day until the limbs become deformed. 

 The muscles atrophy from disuse. The patients lie continu- 

 ally and move about only on the knees or haunches to 

 gather their food. 



Simultaneously, or after the arthritis has disappeared, 

 the sniffling becomes audible, and an examination reveals 

 lesions of the face, consisting of symmetrical, firm and ex- 

 tended tumefactions along each side of the median line of 

 the head. There is no mucous discharge from the nostrils, 

 but the lesions of the face become accentuated. In some in- 

 stances the inferior maxillary alone is afifected, but usually 

 it assumes dimensions proportionate to those of the super- 

 ior maxilla. (Fig. no.) The sniffling may precede the local 

 lesions by three months. The latter develop imperceptibly 

 and the veterinarian is only consulted when the patient ex- 

 hibits the following alarming symptoms : The entire maxil- 

 lary region is swollen, glittering, of a milky whiteness and 

 nearly bereft of hair. The forehead is prominently raised 

 at the frontal arch. The sides of the frontals and the other 

 cranial bones are not implicated. The inferior maxillary is 

 also much tumefied. Its branches are dropped and do not 

 reach the anterior extremity of the premaxilla by several 



