Efficacy and tolerance of yeast cell wall as an immunostimulant in the diet of Japanese seabass (Lateolabrax japonicus)

• Published in: Aquaculture 2014-08, Vol.432, p.217-224
• Main Authors: Yu, H.H., Han, F., Xue, M., Wang, J., Tacon, P., Zheng, Y.H., Wu, X.F., Zhang, Y.J.
• Format: Article
• Language: English
• Subjects: Aeromonas veronii; Agnatha. Pisces; Animal and plant ecology; Animal aquaculture; Animal behavior; Animal productions; Animal, plant and microbial ecology; Aquaculture; Autoecology; Bacterial challenge; Biological and medical sciences; Dicentrarchus labrax; Diet; Efficacy; Fish; Fundamental and applied biological sciences. Psychology; General aspects; Immune response; Lateolabrax japonicas; Lateolabrax japonicus; Sea water ecosystems; Synecology; Tolerance; Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution; Yeast; Yeast cell wall
• ISSN: 0044-8486; 1873-5622
• DOI: 10.1016/j.aquaculture.2014.04.043

The effects of dietary yeast cell wall (YCW) on the growth, immune response and cumulative survival rate after Aeromonas veronii challenge were investigated in Japanese seabass, Lateolabrax japonicus. Six high soybean meal (SBM) inclusion diets were prepared with YCW levels at 0 (Y0), 250 (Y1), 500 (Y2), 1000 (Y3), 2000 (Y4), and 20,000 (Y5) mg/kg, respectively. The highest YCW level (20,000mg/kg) was designed as the 10 fold of the highest recommended level (2000mg/kg) for tolerance evaluation. In addition, a positive control (FM) with higher fishmeal level and a negative control (Fla) with 4mg/kg flavomycin based on Y0 diet were designed. Each diet was fed to six replicates of 30 Japanese seabass (18.3±0.01g) for 72days. The growth performance of Y0 group was lower than that of FM group. Optimal levels (1000–2000mg/kg) of baker's YCW improved the growth performance and intestinal mucus development of Japanese seabass, while 500mg/kg YCW enhanced immune response and cumulative survival after challenged with A. veronii. Flavomycin inclusion negatively affected the growth and immune response of fish. The present study proved that the highest recommended dose of YCW was 2000mg/kg, and 10 fold of safety margin was obtained. •Efficacy and tolerance of YCW in diet of Japanese seabass were tested.•Growth, survival after bacterial challenge in basal and Flavomycin diet were lowest.•1000–2000mg/kg of YCW improved the growth and intestinal mucus development.•YCW inclusion improved the immunity response of fish after bacterial challenge.•The highest efficacy dose of YCW was 2000mg/kg, and safety margin was 10 fold.