Effects of copper on the physiological responses of the commercial crab <i>Lithodes santolla</i> (Decapoda: Anomura) larvae

Abstract

SUMMARY: Effects of copper toxicity on zoea I of Lithodes santolla (Decapoda: Anomura) were analysed. The 96-h LC 50 was estimated, resulting in 298.5 µg L -1 . Groups of larvae were exposed to sublethal concentrations (40, 80 and 160 µg L -1 ) for 96 h. Oxygen consumption, ammonia excretion, O:N atomic ratio, lipid peroxidation (LPO) and body water content were measured. Oxygen consumption of treated groups (mean 46.92 ± 8.03 µg-atom O 2 h -1 mg -1 ) did not differ significantly with control. Ammonia excretion decreased by 60% at higher Cu concentration (1.61 ± 0.65 µg-atom N-NH 3 h -1 mg -1 ), leading to a 117% increase in the O:N ratio. LPO values during the exposure time were higher in all treatments than in the controls. The water content was significantly higher in treatments than in controls. The highest concentration assayed, which represents about 50% of 96-h LC 50 , had evident effects on the parameters analysed. The values of copper in water reported for the coastal zone of Ushuaia bay exceed the value established by the United States Environmental Protection Agency (USEPA) for ambient water quality criteria. Therefore, the results obtained in the present study are a contribution to the study of potential effects of copper as a common stressor in the first larval stage of this commercial species of the Beagle Channel.Keywords: crustacean larvae, oxygen consumption, ammonia excretion, O:N atomic ratio, lipid peroxidation, copper. RESUMEN: Impacto del cobre sobre las respuestas fisiológicas de la larva del cangrejo comercial Lithodes santoLLa (Decápoda: Anomura). -Los efectos de la toxicidad del cobre sobre la zoea I de Lithodes santolla (Decapoda: Anomura) fueron analizados. La CL50 96-h fue estimada en 298,5 µg L -1 . Grupos de larvas fueron expuestos a concentraciones subletales (40; 80 y 160 µg L -1 ) durante 96 horas. El consumo de oxígeno, excreción de amonio, relación atómica O:N, lipoperoxidación (LPO) y contenido de agua corporal fueron medidos. El consumo de oxígeno de los grupos tratados (media 46.92 ± 8.03 µg-átomo O 2 h -1 mg -1 ) no difirió significativamente del control. La excreción de amonio disminuyó un 60% en la mayor concentración de Cu (1.61 ± 0.65 µg-átomo N-NH 3 h -1 mg -1 ) produciendo un incremento del 117% en la tasa O:N. Los valores de LPO a lo largo de la exposición fueron mayores en todos los tratamientos respecto al control. El contenido de agua corporal fue mayor en los tratamientos que en el control. La mayor concentración ensayada, que representa alrededor del 50% de la CL50 96-h estimada produjo efectos evidentes sobre los parámetros analizados. Los valores de cobre en agua reportados para la zona costera de bahía Ushuaia exceden los establecidos por la Agencia de Protección Ambiental de Estados Unidos (USEPA) como criterio de calidad ambiental. Por esta razón, los resultados obtenidos en el presente estudio se convierten en una contribución sobre el impacto potencial del cobre como un estresor común durante el primer estadio larval de esta importante especie comercial ...

Effects of water-borne copper on the survival, antioxidant status, metallothionein-I mRNA expression and physiological responses of the Chinese mitten crab, <em>Eriocheir sinensis</em> (Decapoda: Brachyura) larvae

“…The 96-h LC 50 values of copper for E. sinensis larvae were 0.16 and 0.21 mg L -1 at different growth stages, respectively. Copper toxicity for E. sinensis was of the same order of magnitude as for other crustacean larvae (Munshi et al 1996, Ferrer et al 2003, Amin and Comoglio 2010. The results obtained in this study showed that the lethal effects of copper were greater for zoea 1 larvae, suggesting that these larvae are more sensitive than megalopa larvae to water-borne copper.…”

“…Oxygen consumption and other indices related to respiration and metabolism have been used to assess physiological responses under various stressful environments in decapod crustaceans , Dissanayake et al 2008, Amin and Comoglio 2010. High oxygen consumption and RQs after copper exposure have been attributed to ultrastructural damage to the gill epithelium (Yang et al 2007), and their increases reflect an extra metabolic demand in copper-exposed animals.…”

“…This results in protective mechanisms (metallothioneins [MTs] and antioxidant enzymes) failing to protect against lipid peroxidation (LPO) of cell membranes. Numerous investigations have shown the inhibitory effects of copper overdoses on the metabolic processes of crustaceans (Zapata et al 2001, Yang et al 2006a, 2006b, Li et al 2008, Amin and Comoglio 2010, including effects related to aerobic metabolism and oxidative stress. As the reactive oxygen species (ROS), such as the superoxide radicals (O 2 -), hydrogen peroxide (H 2 O 2 ) and hydroxyl radicals (OH -), are also continuously being formed during normal aerobic metabolism and many oxidative stress processes, all organisms have generated antioxidant defences with both enzymatic and non-enzymatic components.…”

“…The lethal effect of copper on different growth stages of crustaceans has been studied extensively, for example in adult blue crabs (Callinectes sapidus) (Martins Cde et al 2011), larval southern king crabs (Lithodes santolla) (Amin and Comoglio 2010) and juvenile freshwater crabs (Barytelphusa cunicularis) (Chourpagar and Kulkarni 2011). However, no study has yet evaluated the acute toxicity of copper on Chinese mitten crabs (E. sinensis) zoea 1 and megalopa larvae.…”

Responses of the resident rocky crab (Halicarcinus planatus, Decapoda) to natural stressors and effluent discharges in Ushuaia Bay, Tierra del Fuego, Argentina

“…Several indexes related to metabolism, such as oxygen consumption, have been used to assess physiological responses in decapods under various stressful pollutants and situations (Amin and Comoglio, 2010;Comoglio et al, 2008;Spice and Weber, 1991). However, oxygen consumption and ammonia excretion in crustaceans are affected by several extrinsic factors such as temperature, dissolved oxygen, ambient ammonia concentration, salinity and pH (Chen and Lee, 1997;Chen and Lin, 1995;Jiang et al, 2000;Kemp et al, 2009;Regnault, 1987).…”