IGF-I gene expression in liver and white muscles confirming promotion effect of dietary NaCl on Growth indices of Giant sturgeon (Huso huso) juveniles

This study was conducted to evaluate the effects of different levels of NaCl used in the diet of farmed Huso huso juveniles based on gene expression of Insulin like growth factor (IGF), and IGF mRNA in the liver and muscle. The NaCl was added in 4 levels of 0 (control), 3, 6 and 9 percent to the basic diet. According to the results, significant changes in IGF 1-mRNA expression were observed in the treatments and control group (p 0.05). The data of IGF gene expressions showed that the highest levels were observed in the control group and in the 3% treatment. Moreover, in the tissue of white muscle, IGf mRNA gene expression showed highest IGF gene expression in the control group (6.4) and lowest expressions were in the 3% (0.7) and 6% (0.8) treatments. Results of growth indices including body weight, SGR, BWI, HSI and ADG showed they significantly increased in all treatments. Moreover, significant differences were observed among treatments and the control group (p 0.05). SGR rose from 1.41 in the control group to 1.58 in treatments 3% and 6% and the BWI increased from 68.88 in the control group to 98.28 in treatment 2. HSI increased from 3.64 g in the control group to 4.37 g in treatment 2. FCR showed significant difference in the control group (1.27) and in the treatment groups (1.14). Statistical analysis of FCR, SGR and IGF mRNA gene expression showed better growth indices in fish fed diets containing NaCl.