Title : Advancing disease resistance in largemouth bass: Effects of ß glucan on immunity and survival rates
Abstract:
β-glucan is widely used in aquaculture due to its immunostimulatory effects, but the specific effect and potential regulatory mechanism on largemouth bass (Micropterus salmoides) are still unclear. Here, we evaluated the effects of b-glucan on growth, immunity, resistance to Aeromonas schubertii and survival rate. Four experimental diets were designed with b-glucan supplementation levels of 0 (control), 100 (LA-100), 200 (MA-200), and 300 (HA-300) mg kg-1, and each diet was fed to largemouth bass (79.30 ± 0.50 g) in triplicate for 70 days, followed by a 3-day challenge experiment. Results showed that different b-glucan supplementations had no significant effects on growth performance and whole-body composition. Fish fed a diet with 300 mg kg-1 b-glucan significantly increased the activity of lysozyme than those fed diets with 0 and 100 mg kg-1 b-glucan. In addition, the survival rate of largemouth bass in b-glucan supplementation groups was significantly higher than the control group at 12- and 24-h challenge by Aeromonas schubertii. The findings of this study provided new insights that will be valuable in future studies to elucidate the mechanism of immunity enhancement by b-glucan.
Keywords: Largemouth bass, β-Glucan, growth, immunity, Aeromonas schubertii
