Encephalitis in turkey poults due to Dactylaria (Diplorhinotrichum) gallopava--a case report and its experimental reproduction

Mycotic encephalitis was the cause of death in a flock of Nicholas turkey poults in South Carolina. Symptoms included leg paralysis and torticollis, with mortality reaching 20%. Grossly visible large granulomatous lesions occurred in the brains. The eyes of some birds contained opaque areas. The fungus Dactylaria (Diplorhinotrichum) gallopava was isolated from the brains and eyes. Similar symptoms, lesions, and mortality were produced in 1-day-old turkey poults by intratracheal inoculation of a spore suspension of D. gallopava. Histopathological studies of the granulomatous areas of the brain and lung revealed massive inflammatory cellular infiltration and coagulative necrosis with extensive giant cell formation. Hyphal elements were demonstrated in these areas. The fungus can be identified by the gross appearance of the colony and by demonstration of the characteristic two-celled spores. Careful cultural studies must be done to differentiate encephalitis caused by D. gallopava from that caused by Aspergillus fumigatus or Arizona hinshawii.