Short CommunicationPerkinsus sp. infecting oyster Crassostrea rhizophorae (Guilding, 1828) on the coast of Bahia, Brazil

This study investigated the occurrence of the protozoan Perkinsus in the oyster Crassostrea rhizophorae on the coast of Bahia State, Brazil. The oysters (n = 900) were collected in February-March and July-August 2010. The Ray's fluid thioglycollate medium (RFTM) analysis of gills and rectum revealed hypnospores of Perkinsus sp. with a high mean prevalence (63%). The infection intensity varied from very light to advanced. The polymerase chain reaction confirmed Perkinsus in 87.2% of the RFTM-positive oysters. Histological analysis showed trophozoites and schizonts phagocytized by hemocytes, mainly in the intestine and the stomach epithelium.

Hypnospores of Perkinsus sp. in the gills of an oyster Crassostrea rhizophorae with advanced infection, stained with lugol, on the coast of Bahia, northeast Brazil. Bar = 100 μm. Rosana Pinho Brandão, Guisla Boehs, Rachel Costa Sabry, Liliane Oliveira Ceuta, Mariane dos Santos Aguiar Luz, Fernando Ramos Queiroga, Patrícia Mirella da Silva.Highlights► This is the first record of Perkinsus in oysters in Bahia, northeast Brazil. ► The mean prevalence of Perkinsus sp. in C. rhizophorae was considered high (63%). ► Infection levels ranged from very light to advanced by RFTM. ► The parasite is being fought with great efficiency by the oysters defense cells. ► This is an initial step toward understanding Perkinsiosis in oysters in Brazil.