Growth performance of European whitefish [Coregonus lavaretus (L.)] under a constant light and temperature regime

摘要

Growth, feed intake and maturation were monitored in a fast-growing benthivore morph of European whitefish [Coregonus lavaretus (L.)] held under constant light (LD 24:0) and temperature conditions (10°C) for 415 days. Their growth was best described by polynomial regression model and no indication of seasonal patterns (e.g. winter depression) in growth rates was found. There was no significant difference in food conversion ratio (FCR) between periods during the experiment and the FCR was favourable (0.84). Furthermore, there were no differences in growth between males and females. None of the fish became sexually mature by the time the experiment was terminated, although they had reached a mean size of about 444 g. The European whitefish seems to be a promising aquaculture species as the growth rate was relatively high with a remarkable homogenous growth performance between individual fish within each experimental unit, a relatively favourable FCR, a low degree of agonistic behaviour and negligible growth depression due to internal biological rhythms or gonad maturation. These results were obtained at relatively low temperatures that should be beneficial for sustainable cost-effective farming conditions in cold climate condition in northern Scandinavia.