Parasites in the mangrove oyster Crassostrea rhizophorae cultivated in the estuary of the Graciosa River in Taperoá, Bahia

Abstract

Parasites in the mangrove oyster Crassostrea rhizophorae cultivated in the estuary of the Graciosa River in Taperoá, BahiaParasitos na ostra-do-mangue Crassostrea rhizophorae cultivada no estuário do rio Graciosa em Taperoá, Bahia AbstractIn this work, parasites associated with the mangrove oyster Crassostrea rhizophorae were studied at a cultivation unit in the estuary of the Graciosa River in Taperoá, Bahia. On a monthly basis, between April 2011 and March 2012, 20 oysters were collected, measured and fixed in 10% formaldehyde. In order to identify the parasites, routine histological techniques were used. The specimens were embedded in paraffin and sections, 7 µm thick, were cut. These were then stained with Harris hematoxylin and eosin and were examined using an optical microscope. The parameters analyzed to investigate water quality showed that the temperature ranged from 23.9 °C to 29.3 °C, water salinity from 0.4 to 24.2 Practical Salinity Units PSU and recorded rainfall from 80 mm to 406.4 mm/month. During the parasitological analyses, infestation of the polychaete Neanthes succinea was observed in 41% of the oysters. Through histological techniques, the following parasites were identified: colonies of Rickettsia-like organisms (RLOs); the protozoa Nematopsis sp. and Ancistrocoma sp.; the turbellarian Urastoma sp.; the metacestode Tylocephalum sp. and an unidentified tapeworm. The data collected showed that there was low-intensity infection with and prevalence of parasites, except for Nematopsis sp., thus attesting that these cultivated oysters were in a healthy condition.Keywords: Histology, protozoa, Nematopsis sp., Neanthes succinea, bivalves. ResumoNo presente trabalho, parasitos associados à ostra-do-mangue Crassostrea rhizophorae foram estudados em uma unidade de cultivo no estuário do rio Graciosa em Taperoá, Bahia. Mensalmente, entre abril de 2011 e março de 2012, 20 ostras foram coletadas, mensuradas e fixadas em formol a 10%. Para a identificação dos parasitos, foram utilizadas técnicas histológicas de rotina, com inclusão em parafina e obtenção de cortes com 7µm, corados com hematoxilina de Harris e eosina e examinados em microscopia de luz. Os parâmetros analisados para a qualidade da água mostraram que a temperatura variou de 23,9 °C a 29,3 °C, a salinidade de 0,4 a 24,2 PSU e a pluviometria de 80 mm a 406,4 mm/mês. Nas análises parasitológicas foram observadas infestações do poliqueta Neanthes succinea em 41% das ostras. A partir das técnicas histológicas foram identificados os seguintes parasitos: colônias de organismos assemelhados a Rickettsiae (RLOs); os protozoários Nematopsis sp. e Ancistrocoma sp.; o turbelário Urastoma sp.; o metacestóide Tylocephalum sp. e um platelminto não identificado. Os dados obtidos mostraram baixa intensidade de infecção e prevalência de parasitos, exceto para Nematopsis sp., atestando a boa condição de saúde das ostras no cultivo.

Ultrastructure of phagocytes and oocysts of Nematopsis sp. (Apicomplexa, Porosporidae) infecting Crassostrea rhizophorae in Northeastern Brazil

“…The data from these studies do not allow comparative ultrastructural descriptions in relation to species that had previously been described (AZEVEDO & MATOS, 1999;AZEVEDO & PADOVAN, 2004;MAGALHÃES et al, 2006). These descriptions of undetermined Nematopsis species (BRITO et al, 2010;COVA et al, 2015;LUZ & BOEHS, 2015;PINTO & BOEHS, 2008;SABRY & MAGALHÃES, 2005) seem to correspond to the morphological characteristics of oocysts of the genus Nematopsis infecting Brazilian fauna that had previously been described.…”

“…Considering that some undetermined species of Nematopsis occurring in several hosts belonging to different species (ABDEL-BAKI et al 2012;AZEVEDO & CACHOLA, 1992;BOEHS et al, 2010;BRANDÃO et al, 2013;BRITO et al, 2010;CANESTRI-TROTTI et al, 2000;COVA et al, 2015;KUA et al, 2013;PINTO & BOEHS, 2008;QUEIROGA et al, 2015;SABRY & MAGALHÃES, 2005;SUJA et al, 2016;TUNTIWARANURUK et al, 2004TUNTIWARANURUK et al, , 2015, it is acceptable to think that many of the species thus described may correspond to previously described species. On the other hand, several Nematopsis species have been described from the gregarine stage of the schizogonic phase (CHAMBOUVET et al, 2016;CHAKRABORTI & BANDYOPADHYAY, 2010;JIMÉNEZ et al, 2002;PRASADAN & JANARDANAN, 1996, 2001SHANAVAS et al, 1989).…”

Characterisation of the intracellular protozoan MPX in Scottish mussels, Mytilus edulis Linnaeus, 1758

“…Some of them are extracellular, and live as commensals in the lumen of the digestive gland tubules and acini, such as Stegotricha enterikos Meyer, 1993 (Bower andMeyer, 1993) or Ancicostroma sp. (Cova et al, 2015), or in association with or attached to the gills, such as Trichodina spp. (Xu et al, 2000).…”

Parasitism by Nematopsis sp. (Apicomplexa: Eugregarinida) in Mytella guyanensis at the Marine Extractive Reserve Baía do Iguape, Bahia, Brazil

“…Despite of the infection by Nematopsis sp. being associated to a focal hemocytic reaction without significant effects to the bivalve health, as verified in studies in the state of Bahia (COVA et al, 2015), Paraíba (QUEIROGA et al, 2015), and Sergipe (SILVA et al, 2015. Azevedo and Cachola (1992) showed that high levels of infection by Nematopsis sp.…”