The use ofPseudoalteromonassp. F15 in larviculture of the Yesso scallop,Patinopecten yessoensis

A 49-day rearing trial was conducted to investigate the effects of Pseudoalteromonas sp. F15 on growth, survival, digestive and immune-related enzyme activities in larval and juvenile Yesso scallop, Patinopecten yessoensis. Larvae (Day 2 post-fertilization) (d2 PF)) were provided with a diet only of microalgae (control) and supplemented with F15 at final concentrations of 1×104 and 1×106 cells/mL, respectively. Results indicated that the specific growth rates and survival rates of umbo larvae (d13 PF), crawling pediveliger larvae (d28 PF) and juveniles (d51 PF) fed the F15 supplementation diets at 104 and/or 106 cells/mL were significantly higher than those fed the diet of microalgae. Larvae and juveniles fed 104 and/or 106 cells/mL F15 supplementation diets showed a significant increase in pepsin, amylase and cellulase activities compared with the control group. The lysozyme, superoxide dismutase and catalase activities of larvae and juveniles fed the F15 supplementation diets at 104 and/or 106 cells/mL significantly increased compared to those fed the diet of microalgae. In addition, F15 protected juveniles against challenge with Vibrio splendidus. These data suggest that F15 can be useful in scallop larviculture.