Jaw disease in macropod marsupials: bacterial flora isolated from lesions and from the mouths of affected animals.

Bacterial infections of the jaws are a common cause of death in macropods. Lesions and oral cavities from 50 affected animals yielded wide ranges of aerobic and anaerobic organisms. The most frequent isolate from lesions (81%) was Fusobacterium necrophorum, generally combined with other bacteria, but in 5 lesions, in pure culture. It was also isolated from 61% of mouths and this was the chief difference between the oral flora of affected and normal macropods. Other groups of organisms isolated from over 50% of lesions were: Gram-negative aerobic and anaerobic rods, streptococci, anaerobic Gram-positive cocci. Actinomycetes were isolated from 29% of lesions and from one lesion in pure culture. Differences in the flora were detected between lesions in bone and soft tissue and between closed and open lesions. Antibiotics were given to 22 animals, but without significant differences in frequencies of isolation of organisms between treated and untreated groups, and with no permanent elimination of infection. It was concluded that, while different organisms might be present in the complex of "jaw disease", the pathogenic agent in the majority of cases was F. necrophorum. Actinomycetes were capable of producing lesions in bone, but their role in "jaw disease" remains undefined.