Enhancing Growth and Intestinal Health in Triploid Rainbow Trout Fed a Low-Fish-Meal Diet through Supplementation with <i>Clostridium butyricum</i>
Chang’an Wang,
Fangyuan Li,
Di Wang,
Shaoxia Lu,
Shicheng Han,
Wei Gu,
Haibo Jiang,
Zhuang Li,
Hongbai Liu
Affiliations
Chang’an Wang
Key Laboratory of Aquatic Animal Diseases and Immune Technology of Heilongjiang Province, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070, China
Fangyuan Li
Key Laboratory of Aquatic Animal Diseases and Immune Technology of Heilongjiang Province, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070, China
Di Wang
Key Laboratory of Aquatic Animal Diseases and Immune Technology of Heilongjiang Province, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070, China
Shaoxia Lu
Key Laboratory of Aquatic Animal Diseases and Immune Technology of Heilongjiang Province, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070, China
Shicheng Han
Key Laboratory of Aquatic Animal Diseases and Immune Technology of Heilongjiang Province, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070, China
Wei Gu
Key Laboratory of Aquatic Animal Diseases and Immune Technology of Heilongjiang Province, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070, China
Haibo Jiang
College of Animal Science, Guizhou University, Guiyang 550025, China
Zhuang Li
Fishery Technical Extension Station of Jilin Province, Changchun 130012, China
Hongbai Liu
Key Laboratory of Aquatic Animal Diseases and Immune Technology of Heilongjiang Province, Heilongjiang River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Harbin 150070, China
This study evaluates the effects of dietary Clostridium butyricum on growth performance and intestinal health in triploid rainbow trout (Oncorhynchus mykiss). Administered in a 12-week trial, five isonitrogenous and isolipidic feeds contained different C. butyricum levels [G1 (0), G2 (1.6 × 106 CFU/g), G3 (1.2 × 107 CFU/g), G4 (1.1 × 108 CFU/g), and G5 (1.3 × 109 CFU/g)]. Significant enhancements in growth performance, including improved feed conversion ratios and specific growth rates in the G4 group, were indicative of enhanced nutrient utilization, corroborated by optimal digestive enzyme activity levels. Antioxidant capabilities were also enhanced in the G4 group, indicated by increased serum superoxide dismutase and catalase activities, along with a significant decrease in malondialdehyde levels. Gut microbiota analysis indicated a probiotic concentration-dependent modulation of microbial communities, with a marked enrichment in beneficial bacterial phyla like Firmicutes in the G4 group. This microbial shift correlated with significant downregulations in immune-related gene expressions, including interleukins (IL-1β, IL-8), NF-κB, MyD88, and TNF-α, highlighting an activated immune response. Correspondingly, serum lysozyme and immunoglobulin M contents were significantly elevated in the G4 group. Challenge tests with Aeromonas salmonicida exhibited the higher disease resistance of fish fed the G4 diet. In conclusion, the study shows the potential of dietary C. butyricum, especially at 1.1 × 108 CFU/g, in enhancing the growth, health, and disease resistance of triploid rainbow trout through modulating gut microflora and stimulating immune responses.
