Effect of dietary supplementation with melatonin on meat quality, fatty acid profiles and metabolome differences in broiler breast

To assess the effects of melatonin supplementation in the diet on carcass characteristics, meat quality, and the fatty acid profile of broiler breast muscles and the differences in the metabolome by LC-MS, one hundred and twenty-eight healthy 15-day-old Ross308 broiler chickens with similar weights were randomly divided into four groups and fed commercial diets with 0, 20, 40 or 80 mg/kg melatonin (M0, M20, M40, and M80) until 36 days of age. Melatonin supplementation did not significantly influence the carcass characteristics and pH values, drip loss and cooking loss of breast meat (P > 0.05); however, the meat colour showed significant variation with melatonin supplementation (P < 0.05). Furthermore, melatonin supplementation (M20 and M80) significantly decreased the content of fatty acids compared with the control group (P < 0.05). LC-MS metabolome profiling identified 22 differentially abundant metabolites in the M20 group, 52 differentially abundant metabolites in the M40 group, and 37 differentially abundant metabolites in the M80 group compared with the control group, and the main differential metabolites were lipids and lipid-like molecules. Compared with the control group, the metabolic pathways of the melatonin-fed groups were all involved in some aspect of lipid metabolism.