Effect of Different Levels of Dietary [Alpha]-Tocopherol on Ovarian Maturation and Reproductive Performance of Broodstock Litopenaeus Vannamei (Boone)‪.‬

ABSTRACT Effects of 4 grade levels of dietary [alpha]-tocopherol (37.82, 115.64, 349.42 and 522.56 mg [kg.sup.-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.sup.-1] of diet was needed to achieve significantly better ovarian maturation and reproductive performance. KEY WORDS: [alpha]-tocopherol, broodstock, Litopenaeus vannamei, maturation, reproductive performance