Influence of Temperature on Successful European Eel Female Maturation under Controlled Conditions

This study determined the optimum thermal conditions to induce gonad maturity in female The aim of the study was to verify which of the three studied water temperatures: 15 degrees C, 18 degrees C or 21 degrees C is the most suitable for inducing gonad maturation and reaching maturity by the female European eel. The thermal regime during the period of female eel maturation should be established nearly individually, depending on the degree of maturation of spawners and it should be lower than that proposed until recently. The study found that 15 degrees C is the best temperature to bring females of European eel to maturity. Excessively high temperatures were found to cause accelerated gonad maturation and to result in a lower oocyte quality. Moreover, the fish kept at higher temperatures (18 degrees C, 21 degrees C) consume their energy resources (for example, for formation of gonads) faster than those kept in water at 15 degrees C. The highest quality was noted for eggs obtained from females kept at lowest tested temperature.