4.Determination of gastric evacuation time and rate of black sea trout (Salmo trutta labrax Pallas, 1811) larvae through live feed utilization

In this study, F2 Black Sea trout larvae hatched in the Central Fisheries Research Institute hatch ery, were used. The aim of the study was to determine the rate of live feed per meal and the time and rate of the gastric evacuation in Black Sea trout larvae (Salmo trutta labrax Pallas, 1811). Twenty-eight larvae, with a mean weight and length of 0.117±0.01 g and 2.45±0.096 cm, respectively were placed individually and in groups into small test units with 1 litre of fresh water with aeration. In the larvae, fed individually, the stomach evacuation was achieved in 24 hours. Consumption of artemia by larvae ranged from 12 to 163. The artemia in stomach was reduced exponentially by passing time. The gastric evacuation rate was 0.0505 arte mia/hour (P<0.05). On the contrary, in-group feeding, larvae consumed 2 to 99 artemia and the gastric evacuation was completed at the 27th hour. The gastric evacuation rate of the larvae fed in-group was 0.0661 artemia/hours (P<0.05).