Suquet M.,Station Experimentale dArgenton |
Araya R.G.,Station Experimentale dArgenton |
Lebrun L.,Station Experimentale dArgenton |
Queau I.,Station Experimentale dArgenton |
And 2 more authors.
Aquaculture | Year: 2010
Controlled reproduction of the European flat oyster requires the development of tools adapted to this species, including a practical anaesthesia and gonad sampling protocol to facilitate sex determination and the verification of gametogenesis. Three replicate groups of 10 oysters (mean weight±SD: 29.9±8.5g) were anaesthetised in 5L containers using magnesium chloride designed either for laboratory (Flucka®) or agricultural (Dead Sea Work®: DSW) use, at two concentrations (50 or 72gL-1). No significant differences were observed in the percentages of oysters anaesthetised or subsequent oyster mortality with the different anaesthetics or concentrations, but increasing water temperature from 14.9 to 18.8°C significantly increased the number of oysters anaesthetised after 3h. Increasing anaesthesia duration from 1 to 22h significantly increased the percentage of oysters anaesthetised but did not affect subsequent oyster mortality. Gonad sampling of anaesthetised oysters did not increase oyster mortality either. A reliable anaesthesia protocol was, therefore, defined using 50gL-1 DSW® magnesium chloride for a 2 to 3h duration. This protocol was validated by monthly anaesthesia and gonad sampling on the same oysters over a three month period, during which a percentage of 95±2% anaesthetised oysters was observed. Compared with controls (oysters that were neither anaesthetised nor sampled), oyster mortality of monthly anaesthetised batches showed no significant increase. © 2010 Elsevier B.V.