Effects of honey saccharide supplementation on growth performance, amylase enzyme activity, gut microvilli, and microbiome in Cyprinus carpio.

Abstract

Background and aim: Prebiotics, such as saccharides in honey, play a crucial role in improving gut microbiota, digestion, and immune function. This study evaluates the effects of Kapok flower honey saccharides on growth performance, digestive enzyme activity, intestinal morphology, and gut microbiota in common carp (Cyprinus carpio).

Materials and methods: A completely randomized design was implemented with four honey supplementation levels (0% control, 0.5%, 0.75%, and 1%) applied to juvenile C. carpio diets over 30 days. Growth performance, feed utilization, intestinal microvilli structure, gut microbiota, and amylase activity were analyzed using advanced techniques, including high performance liquid chromatography, scanning electron microscopy, and biochemical assays.

Results: Kapok flower honey contains fructooligosaccharides (FOS, 14.76%) and inulin (6.6%). Supplementation at 1% significantly improved weight gain, feed conversion ratio, and specific growth rate. Amylase activity increased with honey supplementation, peaking at 24.13 ± 3.11 U g^-1 protein for the 1% group. Gut morphology analysis revealed longer, denser intestinal microvilli and higher perimeter ratios in honey-treated groups than controls. Microbiota analysis showed increased beneficial Bacillus spp. exclusively in the honey-supplemented groups.

Conclusion: Honey saccharides, particularly FOS and inulin, significantly enhance the growth performance, digestive enzyme activity, and gut health of common carp. Supplementation with 1% honey is optimal, improving feed efficiency and fostering beneficial gut microbiota. These findings highlight honey as a cost-effective, natural prebiotic for aquaculture.