This disease has also been termed calf diphtheria, gangrenous stomatitis, ulcerative stomatitis, malignant stomatitis, tubercular stomatitis, and diphtheritic 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 Löffler, who isolated and described the microorganism which produces the disease. Bang obtained this organism from the diphtheritic 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 by Löffler and since confirmed by other investigators, is Bacillus necrophorus, often spoken of as the bacillus of necrosis. This organism varies in form from a coccoid rod to long, wavy filaments, which may reach a length of 100µ; the width varies from 0.75µ to 1µ. Hence it is described as polymorphic. It does not stain by Gram, but takes the ordinary anilin dyes, often presenting, especially the longer forms, a beaded appearance. A characteristic of the organism, 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 anærobe.