Larval development of Persian sturgeon (Acipenser persicus) with emphasis on determination of start feeding

This study was examined to find determine developing stages and start time of feeding of Persian sturgeon (Acipenser persicus) as an important endemic species of southern part of the Caspian Sea. Daily sampling was done from day of hatching to 26 days post hatch (DPH). Samples were fixed in formalin and total length, yolk sac length, fins length, barbells length, head length and eyes and mouth diameters were measured using a loop equipped with micrometer. During this study, with increasing the age, yolk sac volume was decreased and absorbed in 15 DPH fish with mean total length of 25.7 mm. Melanin plug concentrated in last part of digestive tract in 4 DPH larva with mean TL 15.3 mm at 20 °C, and in 8 DPH (21.3 mm TL) with opening of anal, start to excreted and in 10 DPH (22.8 mm TL) completely excreted. Based on the results, for increasing the growth rate, survival, resistance and also to avoid starvation and cannibalism, it is recommend that to start the feeding of Persian sturgeon larvae from 8-10 DPH when temperature is 18-20 °C.