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

Abstract

Mangrove oysters Crassostrea rhizophorae were sampled monthly in the estuary of Jaguaribe River, on the east coast of Ceará State, Brazil, between August, 2000 and December, 2001, making up 170 individuals. The water temperature varied from 26 to 30 °C and salinity from 21 to 42‰. The animals' size ranged from 3.4 to 7.2 cm height. Macroscopical and histopathological analyses were carried out in the oysters' tissues. The histological exams showed protozoans and metazoans of genera Nematopsis and Tylocephalum, respectively. Nematopsis prevalence varied from 60 to 100% and it was higher in the gills and mantle. The oocysts presented a mean size of 11.5 µm (±1.32) length and 9.1 µm (±1.06) width (n = 30), up to 3 oocysts/phagocyte having been observed. Several animals presented focal hemocitical reaction.

Parasites of economically important bivalves from the southern coast of Bahia State, Brazil

“…According to Lauckner (1983), this cestode completes its life cycle in elasmobranchs, and is more common in tropical and subtropical regions. Previous studies involving C. rhizophorae indicate the digestive gland as the major site of occurrence of this parasite (NASCIMENTO et al, 1986;MAGALHÃES, 2005;SABRY et al, 2007); also, all studies showed encapsulation with intense hemocyte infiltration and in some cases, as in the present study, resorption. The same responses were observed in Tapes semidecussata Reeve, 1864 (Veneridae) (CHENG; RIFKIN, 1968) in Hawaii, and in C. virginica (WINSTEAD et al, 2004) in Florida.…”

“…The high prevalence of the gregarine Nematopsis, especially in C. rhizophorae, is in line with several studies involving coastal bivalves from Brazil, such as on C. rhizophorae (SABRY et al, 2007(SABRY et al, , 2011DA SILVA et al, 2011), M. guyanensis (PINTO;BOEHS, 2008;BOEHS et al, 2010;, Anomalocardia brasiliana (Gmelin, 1791) (BOEHS et al, 2010) and Perna perna (Linnaeus, 1758) . This study also confirmed that gills and mantle were the main organs affected by this parasite, although it may also occur in other anatomical regions such as the digestive gland and foot.…”

“…has been reported to use different species of bivalves as an intermediate host (NASCIMENTO et al, 1986;MAGALHÃES, 2004;MAGALHÃES, 2005;SABRY et al, 2007;BOEHS et al, 2010;DA SILVA et al, 2011;. According to Lauckner (1983), this cestode completes its life cycle in elasmobranchs, and is more common in tropical and subtropical regions.…”

Parasites of the mangrove mussel Mytella guyanensis (Bivalvia: Mytilidae) in Camamu Bay, Bahia, Brazil

“…This very likely compromises the functioning of this organ, interfering with feeding. High prevalence of these gregarines were also found in M. guyanensis elsewhere on the Brazilian coast (Azevedo and Matos, 1999;Pinto and Boehs, 2008), as well as in the mussel Perna perna (L., 1758) (Lima et al, 2001) and the mangrove oyster Crassostrea rhizophorae (Guilding, 1828) (Nascimento et al, 1986;Sabry and Magalhães, 2005;Sabry et al, 2007), but none of these studies noted serious damage caused by this parasite. This contrasts with the situation observed in Cerastoderma edule (L., 1758) by Azevedo and Cachola (1992), who attributed massive study confirms that bivalves can serve as primary and secondary intermediate hosts at the same time, as previously reported (Paperna, 1995).…”

“…Various viruses, bacteria, protists, fungi, and metazoans can parasitise molluscs, often affecting their health and endangering their survival. According to information obtained in several studies (Narchi, 1966;Umiji et al, 1976;Nascimento et al, 1986;Azevedo and Matos, 1999;Boehs and Magalhães, 2004;Sabry and Magalhães, 2005;Sabry et al, 2007;Garcia and Magalhães, 2008;Pinto and Boehs, 2008;Da Silva et al, 2009;Boehs et al, 2010), the most common parasites of the molluscs of economic interest from the Brazilian coast are gregarines of the genus Nematopsis, which use bivalves as intermediate hosts and complete their life cycle in crustaceans (Lauckner, 1983); digeneans, which also use molluscs as intermediate hosts; and the polychaete ECOLOGY Polydora websteri Hartman, 1943 (Spionidae), which occurs mainly in oysters of the genus Crassostrea.…”