Pathological findings in Crassostrea rhizophorae from Todos os Santos Bay, Bahia, Brazil

Abstract

Types and frequencies of pathologies were investigated in Crassostrea rhizophorae before and following heavy oyster mortality in Todos OS Santos Bay, Bahia, Brazil. The sporozoan Nematopsis sp. was the only parasite present in sufficient numbers to be an important mortality factor, but the intensity of Nematopsis infections remained low until after the major die-off. Pathologies such as ceroidosis, reduction or loss of stored glycogen, decreased gametogenesis, edema, and metaplasia of the digestive diverticula were consistent with the hypothesis of an external environmental stress factor that may have caused feeding to cease, the resultant weakness contributing to high mortalities. 8, 1986 Academic Press. Inc.

Simbiontes associados com Anomalocardia brasiliana (Gmelin) (Mollusca, Bivalvia, Veneridae) na Ilha de Santa Catarina e região continental adjacente, Santa Catarina, Brasil

“…Dentre os metazoários, os trematódeos digenéticos são os mais frequentes e considerados os mais importantes parasitos de bivalves (KINNE 1983 (UMIJI et al 1976, LIMA et al 2001, SILVA et al 2002 e em ostras Crassostrea rhizophorae (Guilding, 1828) (NASCIMENTO et al 1986).…”

“…2). De acordo com observações anteriores em outras espé-cies de moluscos bivalves (SINDERMANN 1970, LAUCKNER 1983, NASCIMENTO et al 1986, FIGUERAS & VILLALBA 1988, esse cestóide pertence, muito provavelmente, ao gênero Tylocephalum Linton, 1890 (Lecanicephalidea, Tetragonocephalidae).…”

“…No Brasil, esses parasitos foram observados em ostras C. rhizophorae (NASCIMEN- TO et al 1986). A sua localização na glândula digestiva coincide com os relatos de FIGUERAS & VILLALBA (1988) e de LAUCKNER (1983.…”

First record of parasitism in the mangrove oyster Crassostrea rhizophorae (Bivalvia: Ostreidae) at Jaguaribe River estuary - Ceará, Brazil

“…Oocysts occurrence of Nematopsis in the connective tissue of marine bivalves, mainly in the gills, is widely registered (Nascimento et al, 1986;Azevedo and Cachola, 1992;Bower et al, 1994;Azevedo and Matos, 1999;Carballal et al, 2001). Nevertheless, the pathogeny of this gregarine is very doubtful.…”

“…was recorded in mussels Perna perna in Santa Catarina State, South Brazil (Silva et al, 2002) and in Anomalocardia brasiliana in Ceará State (Araújo and Rocha-Barreira, 2004). Nematopsis occurrence was recorded in C. rhizophorae (Nascimento et al, 1986), and in mussels Mytella guyanensis (Azevedo and Matos, 1999) and Perna perna (Lima et al, 2001). Metazoans of genus Tylocephalum were observed in C. rhizophorae (Nascimento et al, 1986) and in A. brasiliana (Boehs and Magalhães, 2004).…”