Category:Actinomycetes

Actinomycetes organisms are gram positive bacteria that grow slowly on media and produce branching filaments. They are associated with opportunistic infections causing inflammatory responses and granulomatous reactions; animal pathogens include Actinomyces, Arcanobacterium, Actinobaculum, Nocardia and Dermatophilus.

Actinomycetes organisms are non-motile, non-spore-forming bacteria which are anaerobic or facultative anaerobes that typically colonise mucous membranes. They will grow on enriched media and are non-acid fast, Modified Ziehl-Neelson negative when stained.

Clinically, this class of organisms includes Micropolyspora faeni and Thermactinomyces vulgaris - these are implicated in Bovine Farmers Lung and Thermactinomyces vulgaris is associated with the pathology of RAO in horses.