Sarcocystis spp. are cyst-forming coccidia that infect numerous animals species, including several livestock species. Despite the importance of sheep and goat production in Brazil, little it is known about the Sarcocystis species that infect small ruminants in the country and their potential impact on meat condemnation due to the presence of macroscopic cysts of the parasite. The aims of the present study were to determine the frequency of infection by Sarcocystis spp. in goats and sheep intended for human consumption in Bahia State, Brazil, as well as to identify the parasite species in selected samples. The entire tongue, esophagus, and heart were collected from 120 goats and 120 sheep. Tissues were examined for Sarcocystis spp. by macroscopic evaluation, light microscopy, electron microscopy, and molecular tests. Microscopic cysts of Sarcocystis spp. were detected in 95.8 % of sheep and 91.6 % of goats. Using either transmission electron microscopy or partial sequencing of the 18S region of the ribosomal DNA (rDNA) for species identification, Sarcocystis tenella and Sarcocystis arieticanis were observed in sheep and Sarcocystis capracanis in goats. Macroscopic cysts were not detected in the analyzed samples. We concluded that goats and sheep destined for human consumption in Bahia possess high frequencies of Sarcocystis infection. Carcass condemnation due to Sarcocystis macrocysts seems to be rare in the studied region. S. arieticanis and S. capracanis were confirmed for the first time by electron microscopy or by molecular tests in small ruminants from Brazil.

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Most reported isolates of Sarcocystis spp. derived from Brazilian opossums ( Didelphis sp.) have genetic characteristics distinct from the known species of Sarcocystis , but behave similarly as Sarcocystis falcatula , as they are infective to budgerigars. In previous studies, these Brazilian isolates, classified as Sarcocystis falcatula -like, were originated from South and Southeast regions of Brazil. In the current work, we aimed to culture and to perform multilocus sequence analysis of Sarcocystis sp. derived from a Brazilian opossum ( D. aurita / D. marsupialis ) that inhabited the city of Salvador, Bahia, in the Northeast of Brazil. The parasite was isolated in Vero cells, referred here as Sarco-BA1, and propagated in avian cells (DF-1). Molecular analysis of Sarco-BA1 revealed that the nucleotide sequence of the internal transcribed spacer 1 (ITS1) of the rDNA was identical to all isolates (n = 19) of Sarcocystis spp. reported in two studies from South and Southeast regions of the country. Two budgerigars were inoculated with 10 and 1000 sporocysts of Sarco-BA1, respectively, and developed acute sarcocystosis, showing that the parasite behaves like S. falcatula . It was interesting to observe that Sarco-BA1 had almost identical ITS1 and SAG sequences to all 16 isolates of S. falcatula -like recently described in Magellanic penguins ( Spheniscus magellanicus ) rescued on the coast of Espírito Santo state, Brazil. Our results suggest that Sarco-BA1 and S. falcatula -like may represent a single species of Sarcocystis . Propagation of the parasite in a permanent avian cell line significantly improved the yield of merozoites in cell culture. To our knowledge, this is the first molecular study and in vitro isolation of S. falcatula -like derived from Northeastern Brazil. Studies are under way to determine the infectivity of Sarco-BA1 to other animal species, as well as to investigate serological cross-reactivity among Sarco-BA1, S. neurona and related species.

Toxoplasma gondii and Neospora caninum are widespread cyst-forming coccidian parasites of the subfamily Toxoplasmatinae that infect a wide range of wild and domestic animals. Whereas T. gondii is a zoonotic disease, N. caninum is restricted to nonhuman animals. Some chiropteran species can be infected by T. gondii and present fatal toxoplasmosis. In most cases, T. gondii -infected bats are believed to remain asymptomatic and to act as an infection source to other animals. It is not known whether N. caninum can infect bats. We determined infection rates of T. gondii and N. caninum in free-living bats in the state of Bahia, Brazil. Brain samples from 97 bats of seven species, captured in 2008-15, were analyzed by PCRs for T. gondii and N. caninum . Two of the 97 samples were positive for T. gondii DNA. None of the samples were positive for N. caninum DNA, suggesting that the bats were not susceptible to N. caninum infection or that its prevalence was very low.

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