Experimentally induced subcutaneous infection by black pigmented Bacteroides species in rats.

In a rat model of anaerobic subcutaneous abscess developed to study the pathogenicity of pure cultures of black pigmented Bacteroides sp. (Bacteroides melaninogenicus and Bacteroides intermedius) maximum lesions were seen between 7 and 15 days after inoculation. Abscesses were produced by one type strain each of B. melaninogenicus and B. intermedius and by 20 of 25 clinical isolates of black pigmented Bacteroides species.