Journal Article
Habitat-associated detection of Toxoplasma gondii and Sarcocystis spp. in Cetaceans from the Brazilian coast
Thalita Faita; Lara Borges Keid; Natalia Silvestre-Perez; Gláucia Pereira de Sousa; Geovana Carolaine Ramos Thomé; Beatriz de Magalhães Ceron; Samira Costa-Silva; Cristiane Kiyomi Miyaji Kolesnikovas; Pedro Volkmer de Castilho; Fernanda Loffler Niemeyer Attademo; Fábia de Oliveira Luna; Angélica Maria Sánchez-Sarmiento; Raquel Beneton Ferioli; Vitor Luz Carvalho; Aline Ramos Souza; Marta Jussara Cremer; Jenyffer Vierheller Vieira; Adriana Castaldo Colosio; Milton César Calzavara Marcondes; Vanessa Lanes Ribeiro; Carolina Pacheco Bertozzi; Renata Hurtado; Caroline Freitas Pessi; João Carlos Gomes Borges; Arícia Duarte-Benvenuto; Jennifer Morossino; Paula Lima Canabarro; José Luiz Catão-Dias; Rodrigo Martins Soares
Veterinary Research Communications · Vol. 50, Issue 5 · 2026
Abstract
Cetaceans are sentinels of marine ecosystem health and are increasingly exposed to protozoal pathogens. This study investigated the occurrence and molecular identity of Sarcocystidae protozoa in 159 stranded cetaceans representing 21 species along the Brazilian coast. Molecular analysis based on PCR amplification and sequencing of the sarcocystid internal transcribed spacer 1 (ITS1) region revealed infections in 14 individuals, showing a clear habitat-associated distribution. Toxoplasma gondii and Sarcocystis neurona were detected in nine coastal cetaceans, consistent with transmission from terrestrial definitive hosts via land-to-sea runoff. In contrast, a distinct Sarcocystis lineage consistently reported in cetaceans and pinnipeds was identified in six pelagic individuals. Analyses of mitochondrial cytochrome c oxidase subunit I and 18S rDNA markers revealed close similarity to species reported in avian definitive hosts, suggesting a life cycle involving marine or pelagic birds. This ecological segregation reflects differences in parasite transmission pathways and host–habitat interactions. This study provides the first report of S. neurona in Brazilian cetaceans and the first global record of this parasite in Guiana dolphin ( Sotalia guianensis ). Overall, these findings emphasize the role of habitat use in shaping infection patterns and reinforce the importance of a One Health framework to understand land–sea and potentially marine-specific pathogen transmission, as well as its implications for marine wildlife health and conservation.