VESICULAR STOMATITIS OF HORSES AND CATTLE. 3 



containing irritating fungi; necrotic stomatitis, especially affecting 

 calves and pigs, which is caused by infection with the necrosis 

 bacillus; stomatitis contagiosa, or foot-and-mouth disease, which is 

 one of the most highly infectious diseases of animals and caused by a 

 filterable virus; and pustular stomatitis, which is less contagious in 

 character than the former and confined solely to the equine. 



Concerning vesicular stomatitis, the name not only indicates the 

 location of the lesions in the mouth, but also suggests that the 

 vesicles or blisters are characteristic features, being observed at the 

 beginning of the disease. Other names which have been applied to 

 this affection are sporadic aphthae, stomatitis vesiculosa, stoma- 

 titis aphthosa, erosive stomatitis, sore mouth, "blue tongue," and 

 pseudo foot-and-mouth disease. 



ETIOLOGY. 



The literature upon the subject of vesicular stomatitis fails to 

 incriminate definitely any specific organism as the cause of this 

 contagion. Repeated cultural studies of fresh vesicular fluid drawn 

 under aseptic precautions from experimentally infected horses and 

 from field cases have resulted in the isolation of a variety of micro- 

 organisms including micrococci, several short rod-shaped bacilli, one 

 of which takes the bipolar stain, a large Gram-negative spore-bearing 

 rod, and a fungus. Horses and calves were subjected to inocula- 

 tions with cultures of these several organisms, both intravenously 

 and by scarification of the epithelial covering of the tongue and inner 

 surface of the lips, but in no instance was the inoculation successful. 

 An inoculation test of a small micrococcus isolated and cultivated 

 under strict anaerobic environment proved it to be innocuous to 

 horses and calves. Finally, fresh vesicular fluid passed through a 

 Berkefeld (N) filter was completely divested of all infectious quali- 

 ties as determined by inoculation tests of the filtrate in six different 

 experiments. 



Microscopic examination of fresh vesicular fluid by dark-field 

 illumination revealed the presence of micrococci and in addition 

 small bodies with refractive coverings which were very similar in 

 appearance to the spores of a fungus isolated on egg medium from a 

 sample taken from a case of vesicular stomatitis. 



A bacteriological report of the work done by Dr. George Mathers, 

 of the University of Chicago, on the etiology of this disease was read 

 at the annual meeting of the United States Live Stock Sanitary 

 Association, 1 but the evidence presented in favor of the bacillus 

 described was far from conclusive. Through, the courtesy of Dr. 

 James Gregg, of the British remount station at Newport News, Va., 

 several cultures of a microorganism which he had isolated from a 



'Report of Twentieth Annual Meeting of the United States Live Stock Sanitary Association, December, 

 1916, p. 33. 



