Identification of some anaerobic bacteria in nonspecific anaerobic infections in animals.

Over 200 anaerobic bacterial isolates were recovered in a veterinary diagnostic laboratory from nonspecific infectious disease from 72 specimens originating from ten animal species. The majority of isolates were nonsporeforming bacteria and about half were identified to species. Bacteroides species formed the major group and included B. oralis, B. fragilis, B. corrodens, B. ruminicola subspecies ruminicola, B. ruminicola subspecies brevis and various subspecies of B. melaninogenicus. Gram-positive anaerobic cocci constituted the next major group of isolates and the main species identified in cattle was Peptococcus indolicus. Clostridial species were uncommon. Nine specimens yielded a pure culture of an anaerobe and, in samples containing mixtures of bacterial species, each specimen yielded an average of 3.1 anaerobic and 1.4 aerobic bacterial species. The failure to identify many of the isolates is discussed.