Effects of dietary leucine levels on growth, feed utilization, neuro-endocrine growth axis and TOR-related signaling genes expression of juvenile hybrid grouper (Epinephelus fuscoguttatus female x Epinephelus lanceolatus male)

摘要

A 9-week growth trial was conducted to evaluate the effects of dietary leucine (Leu) levels on growth, feed utilization, neuro-endocrine growth axis and TOR-related signaling genes expression of juvenile hybrid grouper (Epinephelus fuscoguttatus female x Epinephelus lanceolatus male). Seven isoenergetic (340 kcal per 100 g of dry matter), isoproteic (53.5% of dry matter) and isolipidic (7% of dry matter) diets were formulated to contain graded Leu levels (1.83%, 2.23%, 2.78%, 3.28%, 3.70%, 4.40% and 4.71%, dry matter basis). Each experimental diet was fed to triplicate groups of 12 hybrid grouper juveniles (average initial body weight 6.92 +/- 0.03 g/fish) which were stocked into small floating cages (L 120 cm x W 70 cm x H 50 cm). Fish were fed twice daily (08:00 and 16:00) to apparent satiation.