Comparison of growth and hematological parameters in juvenile Siberian sturgeon (Acipenser baerii), sterlet sturgeon (Acipenser ruthenus) and its hybrid (Acipenser ruthenus ♀ × Acipenser baerii ♂)

The present study was conducted to compare the growth indices and blood factors of sterlet (Acipenser ruthenus), Siberian sturgeon (Acipenser baerii) and their hybrid (Acipenser ruthenus ♀ × Acipenser baerii ♂) to produce a fish with larger size, larger eggs and more tolerant to environmental conditions than the parents. The hybrid was produced by mixing of the oocytes of one sterlet female with the sperm of a Siberian sturgeon. For this study, 75 juvenile Siberian sturgeon with a mean weight of 32.38 ± 0.36 g, 75 sterlet with an average weight of 32.38 ± 0.41 g and 75 hybrid with an average weight of 32.37 ± 0.41 g each with 3 replicates were distributed in 9 concrete ponds with a volume of 800 liters and reared for 10 weeks. Thirty days after the start of rearing, the growth of juveniles hybrid was significantly higher than that of sterlet (P < 0.05). By continuing to feed the fish until the end of the 72-day study period, hybrid growth was still significantly higher than that of sterlet, but not significantly different from Siberian sturgeon (P > 0.05). The amount of feed intake, weight gain, specific growth rate, and percentage of body weight gain in hybrid were significantly higher than the sterlet (P < 0.05). These indices were lower in hybrid than the Siberian sturgeon but were not significantly different (P > 0.05). The feed conversion ratio of hybrid was significantly lower than that of sterlet (P < 0.05), while no significant difference was found with Siberian sturgeon (P > 0.05). Except for total protein and mean corpuscular hemoglobin, the other hematological indices showed no significant differences among the fish (P < 0.05). The mean corpuscular hemoglobin in hybrid was higher than compared with Siberian sturgeon and sterlet and (P < 0.05). The sterlet × Siberian hybrid showed similarity to the Siberian sturgeon in terms of growth indices, which indicates that it has the characteristics of Siberian sturgeon that has a better growth rate than the sterlet. In terms of blood parameters, the hybrid showed the characteristics of both parents.