Preliminary study on semi-closed incubator efficiency for hatching Persian sturgeon (Acipenser persicus) eggs

The present study investigated the efficiency of semi-closed incubator for hatching the Persian Sturgeon (Acipenser persicus) eggs. The incubator was basically designed according to Vase equipped with collector vessel, recirculation pump and aerator. 50% of water was changed every day. Persian Sturgeon (50 g) fertilized eggs samples were stocked in the incubators with three replica. Water flow rate was set not to harm the eggs and only circulating the eggs. The mortality of embryos and larvae at gasterula stage, formation of S-type heart stage, before hatching and hatching percent were recorded. Our result showed that the incubated circulated eggs completely and the probability of fungal infections was lower than that of flow through incubators. Since water used in semi-closed incubator is far less than that of flow through systems, that semi-closed incubator may be a proper alternative for flow-through incubated systems in future.