Effects of dietary adding vitamin C, astaxanthin, and soybean lecithin on fertilization ability and antioxidant indices in the ovarian fluids of Caspian trout (Salmo caspius) female broodstock

In this study, the effects of dietary addition of vitamin C, astaxanthin, and lecithin on the fertility ability (percentage of fertilization and eyed-eggs) and activity of SOD, CAT and GPx in the ovarian fluids of Caspian trout (Salmo caspius) were investigated. For this purpose, nine different experimental diets: C0A0L0 (0 mg kg-1 vitamin C, 0 mg kg-1 astaxanthin and 0% soybean lecithin), C300A50L0, C700A100L0, C0A50L6, C300A100L6, C700A0L6, C0A100L9, C300A0L9, and C700A50L9 were formulated and the broodstocks (2.51±0.05 kg) were fed for four months. After sexual maturation and spawning, the ovarian fluids were isolated to measure the activity of antioxidant enzymes (AAE) and to evaluate its fertilization ability. The sperm mixture of 9 male broodstocks was used to measure fertilization ability. The results showed an increase in the relative fecundity and AAE in ovarian fluid. The lowest relative fecundity (680±38 eggs per Kg of broodstock weight) and SOD, CAT, and GPx (816.33±67.60 u/ml, 1.29±0.40 nmol/min/ml and 1.06±0.08 nmol/min/ml, respectively) were observed in C0A0L0 which significantly different from other treatments (p<0.05). The highest percentage of fertilization and eyed-eggs were obtained in C300A100L6 (91.66±5.13% and 87.63±1.3%, respectively) which significantly different from the freshwater treatment (77.66±4.16% and 47.86±5.1%, respectively; p<0.05). According to the results of this research, adding of 300 mg kg-1 vitamin C with 100 mg kg-1 astaxanthin and 6% lecithin can increase the relative fecundity, fertilization ability and AAE in ovarian fluids of Caspian brown trout.