Progress in diet development for blue swimmer crab, Portunus pelagicus, juveniles: Effect of dietary phospholipid on survival, development, growth and resistance to osmotic shock

摘要

This study examined the effects of dietary phospholipid (PL) level on survival, growth, development and resistance to osmotic shock of early blue swimmer crab, Portunus pelagicus, juveniles. Six iso-lipidic diets formulated to contain PL at 0 (basal), 30, 60, 90, 120 and 150 g/kg (dry matter) were offered to first-stage crabs (C1) until they achieved C4 stage. Highest survival (93.3%) was achieved by crabs fed diets with PL supplementation levels of 120 and 150 g/kg. Crabs fed diets with PL supplementation levels of 120 and 150 g/kg developed to C4, on average, in 14 days, which was significantly faster (p & 0.05) than crabs in all other treatments. Crabs fed with the same diets also had significant greater dry weight than crabs in other treatments (p & 0.01), except those fed the diet supplemented with 90 g/kg PL (p & 0.05). Dietary PL level markedly influenced survival of juveniles exposed to a stress test of low salinity (7 g/L); most crabs (&87%) fed diets supplemented with PL at 120 and 150 g/kg survived to the end of stress test. Dietary PL levels of 120 g/kg and 150 g/kg are suggested to maximize productivity in early P. pelagicus culture.