Vibrios obtained from the intestinal tracts of wild rats are described. The organism is a normal inhabitant of the lower ileum and cecum of the rat and may be cultivated from these regions. While these rat organisms are in their growth characters and morphology like those found in an intestinal disease of cattle they differ serologically from the cow organisms.
A number of vibrios obtained from the small intestines of calves fed feces from spontaneous diarrhea in cows, natural intestinal disorders of calves, experimentally induced infections of calves, and cultures obtained from Dr. Theobald Smith have been studied. From the close morphological resemblance, similarities in motility, position and number of flagella, tinctorial properties, and the tendency to fragmentation in older cultures, as well as the narrow nutritive requirements, we are led to regard them as a closely allied group and we propose the name Vibrio jejuni. Immunologically as judged by agglutination the organisms have been divided into two groups, the smaller representing two strains originating from diarrhea in cows and the larger comprising one from this source and many from the calf disease. The larger group can be subdivided by means of agglutination absorption into cultures which do not contain the complete antigenic complex and others which do so. Certain freshly isolated vibrios when injected into rabbits incite definite reactions terminating in a localization in the small intestine accompanied by catarrhal inflammation.