Effect of dietary bovine lactoferrin on tolerance to air exposure stress and response in branchial heat-shock protein under low-salinity conditions in grouper Epinephelus coioides

摘要

Augmentation of mass mortality caused by disease and stress has been considered as a serious problem in aquacul-ture worldwide. Therefore, addition of tolerance against stress for fish is an important task in enabling sustainable aquaculture. Recently, we clarified that dietary bovine lactoferrin (bLF) enhances tolerance to high-temperature stress in Japanese flounder, Pamlichthys olivaceus; however, there are no reports on the effect in other important species. In present study, dietary bLF was administrated to juvenile grouper (initial mass = 3.0 g) to investigate its effects on growth response, mucus presence, tolerance to air exposure, and response in branchial heat-shock protein under low-salinity conditions. Test diets containing 4 different concentrations of bLF (0, 400, 800, and 1200 mg bLF/kg diet) were fed to specimens for 30 d.