Pathological and parasitological findings in a Brazilian hoary fox (Lycalopex vetulus, Lund, 1842) infected by Oslerus osleri (Cobbold, 1876) (Nematoda: Filaroididae)

Abstract

Oslerus osleri (O. osleri) is a filaroid nematode of the respiratory tract of domestic and wild canids that leads to parasitic tracheobronchitis. The aim of this study was to report the first occurrence of O. osleri in hoary fox in Minas Gerais State, Brazil. The animal was found struck by vehicle in a periurban area and died before any clinical procedures were attempted. At necropsy the animal showed multiple bone fractures. The mucosa of the middle and distal part of the trachea, and primary bronchi were irregular and moderately thickened, containing numerous cylindrical parasites forming nests, firmly adhered to the mucosa. Histopathological examination revealed diffuse inflammation of the mucosa and numerous parasites embedded in the lamina propria with nematode characteristics. The parasitological evaluation including morphological structures and the size of parasites confirmed the occurrence of O. osleri in the Brazilian hoary fox. The conclusion of this report is that Brazilian hoary fox is naturally infected by O. osleri and this finding is important to know the distribution and epidemiology of this little known parasite in Brazil.