The effect of different iron levels on some of growth indices and carcass composition in Ship Sturgeon Acipenser nudiventris Lovetsky, 1828 juveniles

The present study was performed in order to evaluate the effect of complementary iron on some of the growth indices in Ship sturgeon (A. nudiventris) juveniles. One control group (iron free) and four iron (FeSo4 .7 H 2o) treatment groups with different concentrations (100, 200, 250, 300 mg/kg) were considered in this study. The diets were added to the semi-pure diet for 60 days. Hand-feeding was conducted three times per day. The biometric assessment of the fish was performed at the end of the fourth week and at the end of experimental period. Results showed that the fish fed with 100 mg/Kg iron possessed the highest weight while the weight of the fish fed with 300 mg/Kg had the was not so much increased. Furthermore, the maximum total length, SGR, PER, FE, % BWI, ADG and survivability rate were observed for the fish fed with the first treatment (100mg/Kg) at the end of the experimental period. Results also showed that the fish weight (48.85±4.64g), SGR (1.51±0.043), PER (0.214±0.008), FE (53.54±2.023), BMW% (147.25±6.39), the average daily growth (0.485±0.015), hepatic iron (18.06±0.103), available iron in muscles (10.01±0.09), HSI (4.22±0.35) and the rate of survivability (91.11±7.69) were significantly different between the juveniles fed with different concentration of iron. The minimum amount of FCR (1.87±0.071) was observed for the fish fed with the first treatment, however there was no significant difference for CF between the fish fed with different treatments).The maximum amount of protein percentage and the minimum amount of fat percentage in carcass composition were observed for the fish from the first treatment (63.44±0.62) and the fourth treatment (10±0) respectively. Results of this study determined that some of growth indices in the sturgeon juveniles are significantly affected by the dietary iron (ferrous sulfate). Therefore, it seems that the diet containing 100 mg/kg iron can be considered as optimum diet in rearing condition and for this weight range of fish.