The beneficial impacts of dietary Berberine-loaded chitosan nanoparticles on growth performance and health status of newly weaned rabbits facing heat stress

The study sought to investigate the effect of dietary supplementation of Berberine-loaded chitosan nanoparticles (BER-CNPs) on growth performance and health status of heat stressed rabbits. Ninety -six weaned rabbits, aged 6 weeks were randomly separated into four groups and fed diets containing BER-CNPs at 0 (BER-CNPs0), 20 (BER-CNPs20), 40 (BER-CNPs40), and 80 (BER-CNPs80) g/kg for 8 weeks. Through polynomial regression, the optimal doses of BER-CNPs were 50, 45, 46, and 50 mg/kg for average daily gain, feed conversion ratio, rectal temperature, and respiration rate, respectively. The dressing percentage and the relative weight of liver were significantly higher in the BER-CNPs40 group than the control. Blood protein, lipid profile, glucose metabolism and NF-Kb decreased significantly in the BER-CNPs40 group compared to control and all other treated groups (p < 0.05). Pathological perturbations in liver tissues triggered by heat stress were successfully returned to a state closely resembling normal hepatic morphology through co-treatment with BER-CNPs. Liver functions significantly improved in the BER-CNPs40 and BER-CNPs80 groups compared to the control. The activities of antioxidants indices significantly improved in the BER-CNPs40 group compared to the control. Pro inflammatory response significantly improved in both of BER-CNPs40 and BER-CNPs80 groups compared to the control. However, the BER-CNPs40 group exhibited significant increases in the levels of lysozyme, nitric oxide, and cellular immunity. Overall, the dietary addition of BER-CNPs at levels of 40–50 mg/kg diet could be an effective strategy to enhance the growth performance, feed efficiency, and health status of growing rabbits during the summer season.