Among pinnipeds, four Otariidae species (eared seals) have been reported as occasional or frequent vagrants along the coast of Brazil, mainly in the southern region. These animals usually arrive debilitated during winter and are directed to rehabilitation. Nevertheless, available information on sanitary aspects of stranded pinnipeds in Brazil is limited. Increased fur seal strandings (n=23) were recorded during the 2018 winter season in southeast Brazil (Iguape, Ilha Comprida, and Ilha do Cardoso, Sao Paulo State) compared to 2017 (n=2). Of these 23 fur seals, two were found dead and were in a good postmortem condition, and four died during rehabilitation and were subsequently necropsied. The remaining fur seals were not analyzed due to advanced decomposition (9/23) or successful rehabilitation (8/23). Herein, we report the antemortem hematology (n=4) and postmortem pathologic, parasitologic, and molecular analysis results as well as the most likely cause of stranding and/ or death (CSD) in five free-ranging juvenile South American fur seals (Arctocephalus australis) and one free-ranging juvenile subantarctic fur seal (Arctocephalus tropicalis). All animals were males, and all but one had poor body condition. Pathologic examinations revealed a variety of lesions, predominantly hemodynamic disturbances, endoparasitism, and inflammatory disease processes of suspected infectious nature. Molecular analyses detected gammaherpesvirus infections in two South American seals and one subantarctic fur seal, Sarcocystis sp. in one subantarctic fur seal, and Neospora spp. in two South American fur seals. All seals were PCR-negative for morbillivirus, flavivirus, and Toxoplasma gondii. The most likely CSDs were: starvation (2), aspiration pneumonia (1), asphyxia (1), predator attack (1), and presumed systemic infectious disease (1). These findings expand the geographic range of various pathogens of pinnipeds and may be of value to first responders, clinicians, and diagnosticians.

Hemotropic Mycoplasma spp. (hemoplasmas) are uncultivable bacteria that infect mammals, including humans. We detected a potentially novel hemoplasma species in blood samples from wild river dolphins in the Amazon River Basin, Brazil. Further investigation could determine pathogenicity and zoonotic potential of the detected hemoplasma.

Mycoplasma spp. are wall-less bacteria able to infect mammals and are classified as hemotropic (hemoplasma) and nonhemotropic. In aquatic mammals, hemoplasma have been reported in California sea lions (Zalophus californianus) and river dolphins (Inia spp.). We investigated Mycoplasma spp. in blood samples of West Indian manatees (Trichechus manatus), pinnipeds (5 species), and marine cetaceans (18 species) that stranded or were undergoing rehabilitation in Brazil during 2002–2022. We detected Mycoplasma in blood of 18/130 (14.8%) cetaceans and 3/18 (16.6%) pinnipeds. All tested manatees were PCR-negative for Mycoplasma. Our findings indicate that >2 different hemoplasma species are circulating in cetaceans. The sequences from pinnipeds were similar to previously described sequences. We also detected a nonhemotropic Mycoplasma in 2 Franciscana dolphins (Pontoporia blainvillei) that might be associated with microscopic lesions. Because certain hemoplasmas can cause disease and death in immunosuppressed mammals, the bacteria could have conservation implications for already endangered aquatic mammals.

The knowledge regarding infectious agents affecting wildlife is crucial for species’ conservation. We hypothesized that herpesviruses are present in wild Neotropical carnivores. Herein, we used DNA polymerase and glycoprotein B broad‐spectrum PCRs to molecularly survey the presence of herpesviruses in spleen and/or lung samples of 53 wild Neotropical carnivores of Brazil, comprising the families Canidae, Felidae, Mustelidae, and Procyonidae. The percentage of PCR‐positives was 28.3% (15/53). An alphaherpesvirus was found in a Neotropical river otter (Lontra longicaudis, 1/1), a betaherpesvirus in a lesser grison (Galictis cuja, 1/3), and different gammaherpesviruses in Neotropical river otter (1/1), lesser grison (1/3), crab‐eating raccoons (Procyon cancrivorus, 8/9), South American coati (Nasua nasua, 1/2), southern tiger cat (Leopardus guttulus, 1/2), jaguarundi (Puma yagouaroundi, 1/5), and ocelot (Leopardus pardalis, 1/10). None of the tested canids were herpesvirus‐positive. This is the first report of herpesvirus in procyonids, and in jaguarundi, southern tiger cat, lesser grison, and Neotropical river otter. This study broadens the host range of herpesviruses in Neotropical carnivores.

We report the pathologic features of a primary right tibiotarsal productive osteoblastic osteosarcoma with pulmonary metastasis, a unique finding in a Cory's shearwater (Calonectris diomedea).