Platynosomum (Trematoda: Dicrocoeliidae) infection in barn owls (Tyto alba) in Northeastern Brazil.

Platynosomum spp. are parasites that inhabit the gallbladder and bile ducts of various mammals and birds worldwide. Most studies of Platynosomum spp. in birds focus on the observation and morphological characterization of the parasite through parasitological or molecular examinations, with scarce literature describing anatomopathological alterations, mainly histopathological. We report the case of a male barn owl infected with Platynosomum spp.. At necropsy, the barn owl showed dilation with parasites and fibrosis of the intrahepatic bile ducts and gallbladder. Microscopically, it was possible to identify trematodes in the bile ducts associated with a lymphoplasmacytic inflammatory infiltrate. The morphological structures of the worms were described on histopathology and direct examination. The presence of parasitism that is usually cosmopolitan in wild animals represents a risk to the biodiversity of fauna in the region, as well as a warning about the spread and maintenance of the biological cycle of the worm in humans and domestic animals.