[Pathogenicity in the rat of Mycobacterium lepraemurium cultivated in vitro]

The pathogenicity in Sprague-Dawley rats of Mycobacterium lepraemurium cultivated on egg-yolk medium was investigated. The results show that in vitro grown cultures provoked hugh subcutaneous lepromata in rats similar to those produced by the in vivo grown M. lepraemurium. The acid-fast bacilli isolated from lepromata of rats infected with the in vitro or in vivo grown cultures were microscopically and histopathologically identical to each other.