Use of zinc oxide nanoparticles in the growing rabbit diets to mitigate hot environmental conditions for sustainable production and improved meat quality

BACKGROUND: This study evaluated the modulatory effects of zinc oxide nanoparticles (ZnO-NPs) supplementations on the productive performance, blood biochemistry, carcass criteria, and meat quality of White New Zealand rabbits reared under hot conditions. A total of 125 White New Zealand male rabbits (body weight, “650 ± 11”, 30 days old) were assigned to five treatment diets: basal diets supplemented with ZnO-NPs at 0, 20, 40, 60, or 80 mg/kg for 60 days. Each treatment was replicated 25 times with one rabbit each. RESULTS: The body weight (BW), BW gain, and feed intake linearly increased with zinc oxide nanoparticle supplements. Supplementation of ZnO-NPs at 20, 40, 60, and 80 mg/kg significantly improved (linear, P < 0.05) the feed conversion ratio compared to the control group. Moreover, supplementation of ZnO-NPs at these inclusions 20, 40, 60, and 80 mg/kg significantly (P < 0.05) decreased the serum cholesterol, alanine aminotransferase, and aspartate aminotransferase, creatinine, and urea compared to control group. The lipid oxidation was lower, and the water holding capacity of rabbit meat was improved (P < 0.001) in rabbits fed on 20, 40, 60, and 80 mg/kg ZnO-NPs supplemented diets compared to control. CONCLUSION: The results suggested that dietary supplementation of ZnO-NPs (20–80 mg/kg) can mitigate the negative impacts of heat stress on rabbit performance and health. Its supplementation improved growth performance and meat physicochemical properties, and blood biochemistry parameters of White New Zealand rabbits.