Effects of three kinds of lactic acid bacteria on growth, antioxidant and immune functions of Channa argus

In order to study the effects of lactic acid bacteria (LAB) on the growth, antioxidative status and immunity of Channa argus, 360 C. argus with an initial weight of (3.43 ± 0.05) g were selected and randomly divided into 4 groups. Each group was set up with 3 replicates, each with 30 C. argus. They were fed with basic feed and test feed supplemented with 10⁸ CFU Lactococcus lactis L21 (L21 group), Lactobacillus plantarum W21 (W21 group), and Enterococcus faecalis L2 (L2 group). After 8 weeks, we collected the serum, liver, spleen, kidney and intestinal tissues to determine related indicators and genes expression. The results showed that compared with the control group, the three LAB added to the feed could significantly increase the average weight gain rate (AWGR), specific growth rate (SGR) and feed efficiency rate (FER) of C. argus, and the L21 group was significantly higher than other groups. Compared with the control group, the activities of superoxide dismutase (SOD), catalase (CAT), glutathione (GSH) and alkaline phosphatase (AKP) in the L2 group were significantly higher than control group, the lysozyme (LZM) activity of the W21 and L2 groups was significantly higher than that of the control and L21 groups, and the immunoglobulin M (IgM) activity of each group was not significant. The genes expression levels of IL-1β, IL-8, IL-10 and TNF-α in various tissues all increased to varying degrees, and LAB could significantly promote the expression of immune-related genes in the intestine. Research shows that under the experimental conditions, L. lactis L21 had the best application effect in C. argus, and it could improve the growth, and immune function of C. argus.