The role of polecats of the genus Putorius Cuvier, 1817 in natural foci of adiaspiromycosis.

Adiaspiromycosis provoked by the fungus Emmonsia crescens was diagnosed in two different species of polecats. In total, 76.2% of steppe polecats (Putorius eversmanni) and 35.6% of dark polecats (P. putorius) were infected. The infection was not demonstrated at all in ferrets (P. furo) reared as fur animals. The differences found in the extent and intensity of infection in the two species of wild polecats are explained by different ecological requirements of these related carnivores. The habitat of the exoanthropic P. eversmanni offers more opportunity for a contact with the pathoergont than that of P. putorius; the latter may occasionally pass over to a pronouncedly hemisynanthropic way of life. The synanthropy of the hosts probably has a negative influence on the life cycle of the fungus. Although the inhalation of aleuriospores is the main route of infection, the ingestion of adiaspores also plays an important role. From this aspect are also evaluated the trophic relationships between mustelid carnivores and small rodents: the predatory species gets into contact with the adiasporic phase of the pathoergont localized in the lungs of wild rodents. The extremely high extent and intensity of infection by the elements of E. crescens in polecats probably results from the cumulation of both routes of infection.