Effect of dietary β-glucan on growth, survival and regulation of immune processes in rainbow trout (Oncorhynchus mykiss) infected by Aeromonas salmonicida

Serum glutamic oxalacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) levels in the β-glucan groups were significantly lower than in the control group (P ≤ 0.05). The peak of heat shock protein 70 (HSP70) expression in the 0.2% β-glucan group was higher and occurred earlier than in other groups (P ≤ 0.05). These results confirm that 0.1% and 0.2% dietary β-glucan are beneficial for promoting growth in rainbow trout and enhancing resistance against A. salmonicida. Furthermore, β-glucan could play an important role in regulating stress- and immune-related factors in rainbow trout to more quickly fight against bacterial infection.