Potential effects of dietary probiotics with Chinese herb polysaccharides on the growth performance, immunity, disease resistance, and intestinal microbiota of rainbow trout ( <scp> <i>Oncorhynchus mykiss</i> </scp> )

This study evaluated the effect of probiotics (Clostridium butyricum, Bacillus coagulans) and Chinese herb polysaccharides (Astragalus polysaccharides, APS) on growth performance, immunity, disease resistance, intestinal microbiota rainbow trout (Oncorhynchus mykiss). Specimens O. mykiss (n = 360; 79.9 ± 2.2 g) were fed for 42 days with different diets containing a basal diet (control, C0), supplemented 109 CFU/kg C. butyricum + B. coagulans (E1) 100 g/kg APS (E2) as experimental diets. The results indicated that both E1 E2 increased specific rate, reduced feed conversion ratio, optimized muscle composition. Compared control treatment, after days, activities SOD, T-AOC, CAT significantly, while malondialdehyde content decreased significantly in treatment. After Aeromonas salmonicida challenge, cumulative mortality was 80%, 41%, 29% C0, treatments, respectively. abundance Bacillales, Actinomycetales, Pseudomonadales fish intestine Rhodobacterales Rhizobiales decreased. These data showed improved enhanced immunity modulated mykiss.