Comparative study of the growth performance and gonadosomatic index of Beluga (Huso huso) and Persian sturgeon (Acipenser persicus)

In this study, growth performance, gonadosomatic index (GSI), and gonadal histology of beluga (Huso huso) and Persian sturgeon (Acipenser persicus) were investigated for 12 months. Sixty individuals of fifteen-month old beluga and Persian sturgeon with body mean weight of 781±55 g and 469.5±38 g, respectively, were distributed in the concrete tanks (5×1×1 m) with water capacity of 2.5 m3 in triplicate. At the end of the experimental period, total weight of beluga and Persian sturgeon were 3518.11 and 1561.23 g, respectively, and weight gains were 2737.11 and 1091.73 g, respectively. The differences of SGR values between two species were significant only in the first six-month period; the SGR values of beluga in the first and second three-month period, , 0.64% and 0.49%, respectively, were significantly higher than of Persian sturgeon, 0.50% and 0.33%, respectively at the same period. The FCR value of beluga (1.43) was significantly lower than of Persian sturgeon (1.69). The gonadosomatic index (GSI) values of Persian sturgeon were significantly higher than of beluga, as at the end of the study period, the values in the beluga and Persian sturgeon were 1.39% and 0.38%, respectively. Number of primordial oocytes was increased significantly in the females of both species and tubules in the beluga testis were observable, whereas developed in the Persian sturgeon testis at the end of experimental period. In conclusion, growth performance of beluga was higher than of Persian sturgeon, while gonadal development in Persian sturgeon was more than in beluga.