Cultivation of sturgeon for the purpose of producing caviar requires the keeping and breeding of female fish. But because there are no sexual differences and no external signs to determine sex in sturgeon even at the time of final sexual maturity, Accordingly, early identification of the sex of sturgeon in aquaculture farms is essential in order to reduce breeding costs and optimize farm management. Normally, one of the possible methods of biopsy or laparoscopy or ultrasound is used to determine the gender of sturgeon. These methods are quite stressful and costly for the fish. Since it is impossible to recognize their gender through external signs, Therefore, the gender of 80% of farmed beluga sturgeon under one year can be recognized by hand, the roughness of the ventral surface and the lateral surface of the female fish. In this regard, the breeder can separate the female fish from the male based on the appearance obtained from the research results without paying the cost and with minimal stress on the fish (due to manipulation).
 

Beluga sturgeon, Sex identification, Roughness, ventral surface, lateral surface, female sex