308 DISEASES OF CATTLE, SHEEP, GOATS, ETC. 



this period, and from reports received it is safe to conclude that 

 more than one-half of mis quantity has actually been injected, 

 whereby the percentage of loss from blackleg has been reduced from 

 10, 15, or 20 per cent, which annually occurred before using, to less 

 than 1 per cent per annum. With these figures before us it is plain 

 that the general introduction of preventive vaccination must be of 

 material benefit to the cattle raisers in the infected districts. More- 

 over, there is every reason to believe that with the continued use of 

 blackleg vaccine in all districts where the disease is known to occur 

 and an earnest effort on the part of the stock owners to prevent the 

 reinfection of their pastures by following 'the direction given, black- 

 leg may be kept in check and gradually eradicated. 



CALF DIPHTHERIA (NECROTIC STOMATITIS). 



Necrotic stomatitis is an acute, specific, highly contagious in- 

 flammation of the mouth, occurring in young cattle and character- 

 ized, locally, by the formation of ulcers and caseo-necrotic patches 

 and by constitutional symptoms, chiefly toxic. 



This disease has also been termed calf diphtheria, gangrenous 

 stomatitis, ulcerative stomatitis, malignant stomatitis, tubercular 

 stomatitis, and diphtheric patches of the oral mucous membrane. 



History. During the last few years farmers and cattlemen in 

 this country, especially in Colorado, Texas, and South Dakota, have 

 increasingly noted the occurrence of enzootics of sore mouth among 

 the young animals of their herds. Instead of healing, like the usual 

 forms, of themselves, these cases, if untreated, die. Careful study of 

 some of them has resulted in their identification with cases reported 

 in 1877 by Dammann, from the shore of the Baltic; in 1878 by 

 Blazekowic, in Slavonia; in 1879 by Vollers, in Holstein; in 1880 

 by Lenglen, in France; in 1881 by Macgillivray, in England, and 

 in 1884 by Loflfler, who isolated and described the micrororganism 

 which produces the disease. Bang obtained this organism from the 

 diphtheretic lesions of calves in 1890, and Kitt likewise recovered 

 the bacillus from similar lesions of the larynx and pharynx of calves 

 and pigs in 1893. 



Etiology. The cause of necrotic stomatitis, as demonstrated 

 iby Loffler and since confirmed by other investigators, is Bacillus 

 necrophorus, often spoken of as the bacillus of necrosis. This organ- 

 ism varies in form from a coccoid rod to long, wavy filaments, which 

 may reach a length of 100 /t; the width varies from 0.75 p. to 1 p.. 

 Hence it is described as polymorphic. It does not stain by Gram, 

 but takes the ordinary aniline dyes, often presenting, especially the 

 longer forms, a beaded appearance. A characteristic of the organ- 

 ism, of great moment when we come to treatment, is that it grows 

 only in the absence of oxygen, from which fact it is described as an 

 obligate anaerobe. 



Very few organisms exhibit a wider range of pathogenesis. Ac- 

 cording to clinical observation up to the present time, Baeillus necro- 

 phorus is pathogenic for cattle, horses, hogs, sheep, reindeer, kanga- 

 roos, antelope, and rabbits. Experimentally it has been proved pa- 

 thogenic for rabbits and white mice. The dog, cat, guinea pig, 



