The multi-enzymes and probiotics mixture improves the growth performance, digestibility, intestinal health, and immune response of Siberian sturgeon (<i>Acipenser baerii</i>)

Abstract

Abstract The inclusion of exogenous digestive enzymes and probiotics is well established in the aquafeed industry. The mixture of multi-enzymes and probiotics improves the feed utilization and wellbeing of aquatic animals compared to the individual supplementation. Herein, we evaluated the exogenous multi-enzyme mixture (beta-glucanase, cellulase, alpha-amylase, protease, xylanase, and phytase) at 250 mg/kg and multi-species probiotic ( Bacillus subtilis , Lactobacillus acidophilus , L. delbrueckii , L. rhamnosus , L. plantarum , and Pediococcus acidilactici ; 1 × 10 10 CFU/g for each bacterial strain) at 2 g/kg on the performances of Siberian sturgeon. The final weight, weight gain, SGR, and PER were markedly enhanced while the FCR was reduced in fish fed multi-enzyme and probiotics premix (P&lt;0.05). Multi enzymes and probiotic mixture significantly increased the total body protein content (P˃0.05). Multi enzymes and probiotic mixture also improved the digestibility of crude protein, dry matter, and crude lipids nutrients (P&lt;0.05). The count of goblet cells, microvilli diameter, microvilli length, outer muscle wall diameter, and enterocyte total absorptive surface were markedly increased (P&lt;0.05) by dietary multienzymes and probiotics mixture. The WBCs and neutrophils showed marked improvements (P&lt;0.05). The levels of glucose, triglycerides, blood urea nitrogen, and total bilirubin were markedly higher in fish fed the control than fish fed the multi-enzymes and probiotics mixture (P&lt;0.05). Significantly, Siberian sturgeon-fed dietary multi-enzymes and probiotics had improved lysozyme activity, total immunoglobulin, and total protein in the skin mucus and serum samples (P&lt;0.05). Further, the serum complement C3 and C4 was higher in fish-delivered multi-enzymes and probiotic mixture than in control (P&lt;0.05). In conclusion, dietary probiotics synergistically enhanced the activity of multi-enzymes and resulted in increased feed utilization, nutrient digestibility, and health status of Siberian sturgeon.