Developmental stages of <i>Sarcocystis</i> spp. in wild birds from Southeastern Brazil, with a review of Accipitriformes-associated species.

Abstract

The genus <i>Sarcocystis</i> comprises apicomplexan parasites associated with clinical manifestations, including reproductive and neurological disorders, in a wide range of domestic and wild animals. Infections by <i>Sarcocystis</i> spp. have been reported in birds on all continents except Antarctica. In this context, the present study reports two cases in which <i>Sarcocystis</i> spp. were identified at different developmental stages, endogenous and exogenous, in wild birds captured in Southeastern Brazil. Oocysts and sporocysts were detected in the feces of a roadside hawk <i>Rupornis magnirostris</i>, captured on Marambaia Island, Rio de Janeiro State, Brazil. In addition, bradyzoite cysts were observed in the muscle tissue of a rufous-bellied thrush <i>Turdus rufiventris</i>, captured in Itatiaia National Park. Accordingly, this study provides comments on the parasitic dynamics of <i>Sarcocystis</i> spp. in a wild environment and discusses the potential species involved in these host-parasite associations. For <i>Sarcocystis</i> sp. detected in the rufous-bellied thrush, based on evidence from previous studies, we strongly suggest that this species is <i>Sarcocystis falcatula</i>. In contrast, for <i>Sarcocystis</i> sp. detected from the roadside hawk, no specific species assignment can be made, as data on hawks acting as definitive hosts of <i>Sarcocystis</i> spp. in South America remain scarce. Although <i>S. falcatula</i> may involve Accipitriformes in its life cycle, members of this order are considered intermediate rather than definitive hosts for this species. Therefore, we present herein a survey of <i>Sarcocystis</i> spp. that involve Accipitriformes in their life cycles, including comparative data on sporocyst measurements for each species.