Search

The genus Sarcocystis contains around 200 species and 25 of these infect snakes. Two Sarcocystis spp. shed by snakes have called special attention of the scientific community. S. nesbitti, which is shed by scrub pythons (Simalia amethistina), causes myopathy in humans that consume water or food contaminated with the parasite. Sporocysts of S. singaporensis, excreted by reticulated pythons (Malayopython reticulatus), is letal for rats and was successfully tested in the biological control of these rodents. A high biodiversity of snakes is found in Brazil, however, scarce information is available about Sarcocystis spp. in Brazilian snakes. Herein, we investigated Sarcocystis sp. in feces of the common boa (Boa constrictor) from Salvador, as it is widely distributed in Brazil and it is also bred in other countries. Feces of 65 boas were examined, and Sarcocystis sp. was found in 1/65 (1.53%) snakes. All snakes were alive, and for this reason, intestinal scrapping, which is the most sensitive method to detect the parasite, was not performed. Morphometric evaluation of sporocysts showed significant differences in their sizes. PCR and multilocus sequencing of four genetic markers (cox1, 18S, ITS1, and 28S) revealed that sporocysts corresponded to a new Sarcocystis species. Sequences of cox1 and 18S had identities of 100% and higher than 98%, respectively, with sequences obtained from the rodent Lagostomus maximus in Argentina. ITS1 and 28S sequences did not match with any known Sarcocystis sp. No ITS1 and 28S sequences were available for the Sarcocystis sp. found in the Argentinian L. maximus. Bioassay using the boa sporocysts was conducted in three mouse lineages and in Rattus norvegicus, but no parasitic stages were detected in these rodents. We concluded that the common boa is probably the definitive host of a new species of Sarcocystis sp. that has L. maximus or related rodents as intermediate hosts.

Abstract Protozoan parasites of the genus Sarcocystis are obligatory heteroxenous cyst-forming coccidia that infect a wide variety of animals and encompass approximately 200 described species. At least four Sarcocystis spp. (S. falcatula, S. neurona, S. lindsayi and S. speeri) use opossums (Didelphis spp.) as definitive hosts, and two of them, S. neurona and S. falcatula, are known to cause disease in horses and birds, respectively. Opossums are restricted to the Americas, but their distribution in the Americas is heterogeneous. Five Didelphis spp. are distributed in South America (D. aurita, D. albiventris, D. marsupialis, D. imperfecta and D. pernigra) whereas just one opossum species (D. virginiana) is found in North America. Studies conducted in the last decades show that Sarcocystis spp., derived from South American Didelphis spp., have biological and genetic differences in relation to Sarcocystis spp. shed by the North American opossum D. virginiana. The aim of this review was to address the peculiar scenario of Sarcocystis species shed by South American opossums, with a special focus on diagnosis, epidemiology, and animal infections, as well as the genetic characteristics of these parasites.