Molecular survey of Hepatozoon spp., piroplasmids, and onchocercids in wild birds from the Brazilian Pantanal

The diversity of Hepatozoon spp., piroplasmids, and onchocercids that parasitize birds worldwide has been underestimated, especially in Brazil. The present work aimed to investigate, using molecular assays, the occurrence of Hepatozoon spp., piroplasmids, and onchocercids in tropical birds from the Brazilian Pantanal wetland, in the states of Mato Grosso and Mato Grosso do Sul. Blood sampling and DNA extraction were performed on 517 birds from 13 avian orders. DNA samples positive to endogenous gene (avian β-actin) were subjected to PCR assays targeting the 18S rRNA gene of Hepatozoon spp. and piroplasmids as well as PCR assays for onchocercids (cox-1, 28S rRNA and 18S rRNA genes). As a result, two onchocercids (0.4%) were identified. None was positive in the PCR assays for Hepatozoon spp. or piroplasmids. The cox-1 sequence detected in Ramphocelus carbo grouped with Cardiofilaria sp., and onchocercid cox-1 sequence obtained from Taraba major grouped with Splendidofilaria spp. This is the first molecular report of onchocercids closely related to Cardiofilaria spp. and Splendidofilaria spp. in birds from the Brazilian Pantanal.