Henneguyosis in gills of : an Amazon freshwater fish.

This study describes aspects of infection caused by Myxozoa of the genus sp. in gills of fish belonging to the species Two sampling were made in the Capim river, close to the Ribeira community, in the municipality of Ipixuna do Pará, State of Pará, Brazil, during the months of August 2018 and March 2019. The animals were captured and transported live to the Laboratório de Pesquisa Carlos Azevedo, at the Universidade Federal Rural da Amazônia (UFRA), in Belém, Pará, Brazil. The animals were examined, and after parasitism was confirmed, Differential Interference Contrast Microscopes were used, to evaluate the parasite spores. Ziehl-Neelsen stain techniques were used in histology. Necroscopic analyses of specimens found parasites in 80% of the hosts (16/20), with whitish-colored cysts in the branchial filaments, containing mature spores of the genus . The histopathological analysis indicated large areas with cystic lesions with associated ischemic necrosis. The descriptions from this study indicate that the parasite drastically compromises the host's respiratory system. Additionally, it is worth noting that parasite fauna studies of fishes in the Capim river are still a vast topic for research; this is the first record of infection by sp. in , captured in the Capim river in Ipixuna do Pará.