Parasites of three commercially exploited bivalve mollusc species of the estuarine region of the Cachoeira river (Ilhéus, Bahia, Brazil)

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

“…Despite the damage caused by infection, there was no apparent inflammatory response in the host. Contrary to what was seen in this study, Boehs et al (2010) observed hemocyte infiltration around dead or degenerating sporocysts in M. guyanensis, while Da Silva et al (2002) reported high hemocyte infiltration in heavily infected Perna perna. According to Bower (1992) and Carballal et al (2001), high infection levels by sporocysts can reduce recruitment at the population level.…”

“…These trematodes are so named due to their forked tail with a very short and wide base during the cercaria phase (WARDLE, 1990). Studies in some species of Mytilidae (LASIAK, 1993;BOEHS et al, 2010; have found macroscopic signs such as an orange color and/or fibrous appearance of the mantle, as indications of the presence of sporocysts, which could not be confirmed in this study. The prevalence levels usually below 10% corroborated the results from several studies involving Mytilidae on the Brazilian coast (DA SILVA et al, 2002BOEHS et al, 2010;), the oyster C. rhizophorae from the Brazilian coast (NASCIMENTO et al, 1986), C. virginica from Florida, USA (WINSTEAD et al, 2004) and M. galloprovincialis from Portugal (FRANCISCO et al, 2010).…”

“…With respect to the RLOs found in both species, the site of infection in the host (the digestive gland), the localized effect, and the absence of a hemocyte response converge with results from recent studies conducted by Da Silva et al (2011) and Sabry et al (2011) on C. rhizophorae and C. gigas (Thunberg, 1793) in Santa Catarina state, and by Boehs et al (2010) and Ceuta and Boehs (2012) on M. guyanensis in Bahia state. Except for the study by Sabry et al (2011), who identified prevalences of up to 30% for C. gigas (coinciding with the results of this study for M. guyanensis collected at Canavieiras, in February 2010), other studies have indicated a low prevalence of these bacteria.…”

“…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.…”