EFFECT OF DIFFERENT LEVELS OF DIETARY α-TOCOPHEROL ON OVARIAN MATURATION AND REPRODUCTIVE PERFORMANCE OF BROODSTOCK LITOPENAEUS VANNAMEI (BOONE)

Effects of 4 grade levels of dietary alpha-tocopherol (37.82, 115.64, 349.42 and 522.56 mg kg(-1) diet) on ovarian maturation and reproductive performance of broodstock shrimp, Litopenaeus vannamei were investigated. The alpha-tocopherol concentrations in hepatopancreas, ovaries, eggs and muscle of female shrimp increased significantly as dietary alpha-tocopherol levels increased. Survival, spermatophore weight, sperm count, gonadosomatic index (GSI), hepatosomatic index (HSI), fecundity and egg diameter were not significantly affected by dietary alpha-tocopherol levels. Average daily spawns, hatching rate and fertilization rate significantly increased as dietary alpha-tocopherol levels increased. Results of this study confirmed the importance of supplementation of alpha-tocopherol to broodstock diets fed to L. vannamei, and suggested that at least 350 mg alpha-tocopherol kg(-1) of diet was needed to achieve significantly better ovarian maturation and reproductive performance.