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The protozoans Toxoplasma gondii and Sarcocystis spp. (Sarcocystidae: Apicomplexa) affect a wide variety of vertebrates. Both have been reported to infect pinnipeds, with impacts on health ranging from inapparent to fulminant disease and death. However, little is known regarding their infections and associated pathology in South American pinnipeds. We used histological techniques to survey for the presence of T. gondii and Sarcocystis spp. in 51 stranded pinnipeds from Brazil. Immunohistochemical and molecular assays were employed in those cases consistent with Sarcocystidae infection. T. gondii cysts were detected in the central nervous system and heart of a South American fur seal Arctocephalus australis, associated with meningoencephalitis, myocarditis and endocarditis, and confirmed by immunohistochemistry. Additionally, this animal presented Sarcocystis sp. cysts in brain and heart tissues. Four additional specimens-2 Subantarctic fur seals A. tropicalis, an Antarctic fur seal A. gazella and another South American fur seal-presented intrasarcoplasmic cysts compatible with Sarcocystis spp. in muscle samples. There was no inflammation associated with the Sarcocystis spp. tissue cysts and all cysts were negative for S. neurona immunohistochemistry. The B1 gene of T. gondii was amplified in the 5 pinnipeds infected by Sarcocystidae protozoans. To our knowledge, this is the first report of toxoplasmosis in wild South American pinnipeds and of Sarcocystis spp. in South American fur seals. Detection of terrestrial parasites in aquatic mammals could be an indicator of their presence in the marine environment.

The poxviruses identified in cetaceans are associated with characteristic tattoo or ring skin lesions. However, little is known regarding the prevalence and progression of these lesions and the molecular characterization of cetacean poxviruses in the Southern Hemisphere. This manuscript describes the progression of poxvirus-like skin lesions in 5 free-ranging Guiana dolphins Sotalia guianensis. Additionally, 151 skin samples from 113 free-ranging cetaceans from Brazil, including 4 animals with tattoo skin lesions, were selected for poxvirus testing. Poxviral DNA polymerase gene PCR amplification was used to detect the virus in β-actin-positive samples (145/151). DNA topoisomerase I gene PCR was then used in Cetaceanpoxvirus (CePV)-positive cases (n = 2), which were further evaluated by histopathology and electron microscopy. Based on photo-identification, adult Guiana dolphins presented regressing or healed poxvirus-like lesions (2/2), while juveniles presented persistent (2/3) or healed and progressive lesions (1/3). CePV DNA was amplified in a common bottlenose dolphin Tursiops truncatus and in a Guiana dolphin. Intracytoplasmic inclusion bodies and viral particles consistent with poxvirus were identified by histology and electron microscopy, respectively. CePV-specific amino acid motifs were identified through phylogenetic analysis. Our findings corroborate previous studies that suggest the placement of poxviruses from cetaceans within the novel CePV genus. This is the first molecular identification of poxvirus in South American odontocetes.