Identification and characterization of plastic debris in the gastrointestinal tract of Guiana dolphins (Sotalia guianensis) from Espírito Santo coast, Brazil.

The Guiana dolphin (Sotalia guianensis) is categorized as vulnerable in the Brazilian list of endangered animals, and its populations suffer from several anthropological threats. In this study, we analyzed the presence of macro, meso, and microplastics (MPs) in Guiana dolphins (n = 12) in Brazil Southeastern coast by analysing their gastrointestinal tract. The MP extractions were carried out with H2O2 (35 %) to remove organic matter. Four specimens ingested meso and macroplastics, including an item of polypropylene of 19.22 cm that was produced about 943 km from the place in which the animal was found stranded. All the specimens analyzed had fragment-type microplastics in their intestines. Blue was the prevailing color, followed by black, green, and red. We highlight the contamination by microplastics in the species, still little investigated, especially the need to understand the contamination by microplastics along trophic levels.

The lungworm, Halocercus brasiliensis (Nematoda: Pseudaliidae), from Guiana Dolphins Sotalia guianensis from Brazil with Pathological Findings.

The Guiana dolphin, Sotalia guianensis, is a small cetacean species found on the Atlantic coast of Central and South America from Honduras to Santa Catarina State, Brazil. The nematode Halocercus brasiliensis infects this cetacean, resulting in lung pathologies and death. The present study aimed to conduct a morphological and morphometric study of specimens of H. brasiliensis collected from S. guianensis from the coast of the state of Espírito Santo, Brazil. For this study, 7 dolphins were collected and examined for the presence of lung parasites. Nematodes were collected and processed for light microscopy, and lung fragments were processed for histological analysis. The nematodes were identified as H. brasiliensis according to their morphology and morphometry. The histopathological analysis revealed mineralization of the bronchiolar cartilage and inflammatory process. The parasitic infections by H. brasiliensis in S. guianensis can contribute to the debilitating status of these cetaceans, resulting in their stranding and accidental capture in fishing nets.