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.

This study investigated the parasites of three commercially important bivalve species (Crassostrea rhizophorae, Mytella guyanensis and Lucina pectinata) from the southern coast of Bahia, Brazil. A total of 540 specimens were collected in August 2009 and February 2010, at three localities. The bivalve specimens were measured on their longest axis, opened, and macroscopically examined for the presence of parasites or signs of disease. They were then fixed in Davidson' solution and subjected to routine histological processing, with paraffin embedding and H&E staining; next, the specimens were examined under a light microscope. . Nematopsis sp. ocorreu em alta prevalência, porém, aparentemente, não causou danos aos bivalves. Bucephalus sp. causou destruição de tecidos, com castração, mas foi pouco prevalente. Os demais parasitos ocorreram em baixa prevalência e intensidade de infecção e sem causar danos.

Foi investigada a infecção de Perkinsus beihaiensis (Perkinsozoa) na ostra Crassostrea rhizophorae em um sistema de cultivo do tipo espinhel e em um estoque natural de ostras no manguezal adjacente ambos localizados no estado da Bahia, Nordeste do Brasil. As colheitas foram realizadas em outubro e novembro de 2012 e em janeiro de 2013. As ostras (n = 300) foram medidas, examinadas macroscopicamente quanto a sinais da infecção e submetidas às técnicas laboratoriais: histologia, ensaio em meio de cultivo de tioglicolato de Ray (RFTM), reação em cadeia da polimerase (PCR) e sequenciamento, que confirmou a identificação do patógeno. As análises histológicas e o RFTM mostraram, respectivamente, prevalência média de 93,3% e de 69%. A infecção foi geralmente leve ou muito leve. Não houve diferença significativa (p > 0,05) entre os ambientes em termos de prevalência ou severidade da infecção. Este é o primeiro registro de P. beihaiensis no estado da Bahia e o segundo em ostras do Brasil e América do Sul.

Oysters of the genus Crassostrea Sacco, 1897 are widely distributed worldwide, being important extractive and cultivation resources in Brazil. Because they have high phenotypical plasticity and congeneric similarity, identifications based on shell morphology are not always safe. The goal of this study was to identify the oysters of the Bahia State, northeast Brazil, using the molecular tools Polymerase Chain Reaction, Restriction Fragment Length Polymorphism, DNA sequencing and phylogenetic analysis. Oysters were collected at 12 sampling stations, from October 2014 to March 2015 and included samples of rhizomes (aerial roots)/stems of the red mangrove Rhizophorae mangle L. and in the sediment near to the underground roots of this one, on berths, natural rock outcrops near the mangrove swamp and in three oyster crops. It was confirmed the presence of two species of oysters: Crassostrea rhizophorae (Guilding, 1828) and C. gasar (Deshayes, 1830) and that the latter was genetically identical to C. brasiliana reported in previous studies on the Brazilian coast. There was no co-occurrence of the two species on the same substrate, but these were found in nearby environments at two sampling points. Crassostrea rhizophorae was observed on the rhizomes/stems of R. mangle, as well as on artificial concrete walls (berths). The semi-buried oysters near R. mangle's subterranean roots and adhered to small rocks of a rocky outcrop were C. gasar, which was also the exclusive oyster of the crops.

This study reports the presence of the pathogen Perkinsus marinus, notifiable to the World Organization for Animal Health (Office International des Èpizooties = OIE) in the oyster Crassostrea rhizophorae in southern Bahia via proteomic analysis. We analyzed Crassostrea brasiliana from a long-line cultivation system and C. rhizophorae from an adjacent mangrove in Porto do Campo, Camamu Bay, Bahia, Brazil. The collections (n = 100) were performed in October 2012. In the laboratory, the oysters were measured and opened to remove the meat, which was steeped in dry ice. For extraction of proteins, adaptation of a protocol used for mussels was used, after which separation in the first dimension was taken by isoelectric focusing (IEF). The peptides were transferred to a Mass Spectrometer. The obtained spectra were analyzed with the ProteinLynx Global Server 4.2 software tool and also by MASCOT (Matrix Science) and compared to the databases of the SWISSPROT and NCBI, respectively. The identification was evidenced by beta-tubulin, Perkinsus marinus ATCC 50983 and protein homology code in the database NCBI = gi | 294889481. This is the first record of P. marinus in Bahia and the fourth in Brazil.Keywords: "Dermo". Diseases. Oysters. Perkinsiosis. ResumoEste estudo relata a presença do patógeno Perkinsus marinus, de notificação obrigatória à Organização Internacional de Epizootias (OIE) na ostra Crassostrea rhizophorae no sul da Bahia, via análise proteômica. Foram analisadas as ostras Crassostrea brasiliana de um cultivo em espinhel e C. rhizophorae de um manguezal adjacente, na localidade de Porto do Campo, Baía de Camamu, Bahia. As coletas (n = 100) foram efetuadas em outubro de 2012. Em laboratório, as ostras foram medidas e abertas para a retirada da carne, que foi macerada em gelo seco. Para a extração das proteínas, foi adotada a adaptação de um protocolo utilizado para mexilhões, após o que foi realizada a separação na primeira dimensão, por focalização isoelétrica (IEF). Os peptídeos foram transferidos para um Espectrômetro de Massas. Os espectros obtidos foram analisados no software ProteinLynx Global Server 4.2 e também pela ferramenta MASCOT (Matrix Science) e comparados com os bancos de dados do SWISSPROT e do NCBI, respectivamente. A identificação foi evidenciada por meio da beta-tubulina, homologia Perkinsus marinus ATCC 50983 e código da proteína no banco de dados NCBI = gi|294889481. Este é o primeiro registro de P. marinus na Bahia e o quarto no Brasil.Palavras-chave: "Dermo". Doenças. Ostras. Perkinsiose.