Effect of low salinity on the yellow clam Mesodesma mactroides

The aim of this study was to determine the lethal salinity (LC50) for the yellow clam Mesodesma mactroides (Bivalvia: Mesodesmatidae) and identify histopathological alterations that could be used to diagnose structural changes in clam tissue. Clams in two size classes (adults and juveniles) were pla...

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Detalles Bibliográficos
Autores: Carvalho, Yuri Bovi Morais, Romano, Luis Alberto, Poersch, Luís Henrique da Silva
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2015
País:Brasil
Institución:Universidade Federal do Rio Grande (FURG)
Repositorio:Repositório Institucional da FURG (RI FURG)
Idioma:inglés
OAI Identifier:oai:repositorio.furg.br:1/5678
Acceso en línea:http://repositorio.furg.br/handle/1/5678
http://dx.doi.org/10.1590/1519-6984.03213
Access Level:acceso abierto
Palabra clave:Yellow clam
Lethal salinity
LC50
Histology
Extreme southern Brazil
Marisco branco
Salinidade letal
CL50
Histologia
Extremo sul do Brasil
Descripción
Sumario:The aim of this study was to determine the lethal salinity (LC50) for the yellow clam Mesodesma mactroides (Bivalvia: Mesodesmatidae) and identify histopathological alterations that could be used to diagnose structural changes in clam tissue. Clams in two size classes (adults and juveniles) were placed in 10 L chambers and exposed to salinities of 35, 30, 25, 20, 15, 10, and 5 g/L. There were triplicate chambers with seven clams each for each salinity. The LC50 values for a 48 h exposure were 6.5 g/L and 5.7 g/L for adults and juveniles, respectively. For a 96 h exposure, the LC50 values were 10.5 g/L for adults and 8.8 g/L for juveniles. The histological examination of yellow clams exposed to 10 g/L for 96 h showed intercellular oedema and necrotic foci in the epithelium of the digestive gland and occlusion of the lumen of the digestive gland. In conclusion, M. mactroides can be characterised as a moderately euryhaline species, tolerating salinities from 35 to 15 g/L.