Microbiome-metabolomics analysis insight into the effects of dietary chromium picolinate on abdominal fat deposition and lipid metabolism of ducks

This research endeavored to explore the impact of Cr-Pic on the abdominal fat deposition and lipid metabolism of ducks, as well as to uncover the mechanisms at play and identify the optimal dietary supplementation level of Cr-Pic. The results showed that adding 0.6 mg/kg Cr-Pic observably increased the body weight and serum levels of adiponectin and leptin, and decreased serum levels of total cholesterol, triglyceride, and low-density lipoprotein cholesterol in ducks at 14 days (P < 0.05). The addition of 0.6 % Cr-Pic was discovered to regulate lipid metabolism and meat quality through its effects on reducing abdominal fat and drip loss, downregulating the mRNA expression of genes involved in lipid synthesis in the abdominal fat and liver, and upregulating the mRNA expression of genes associated with degradation and transport in these tissues (P < 0.05). Untargeted metabolic profiling indicated that the distinct metabolites between the Cr-Pic and Control groups were predominantly associated with pathways involving amino acids. Microbiome analysis showed that Cr-Pic administration altered the microbial genera related to the adjustment of lipid metabolism in the cecum of ducks, such as increasing the proportion of Bacteroides and Lactobacillus, and decreasing the proportions of Alistipes, Methanobrevibacter, Romboutsia, and Peptostreptococcus (P < 0.05). In summary, Cr-Pic shows promise in reducing the abdominal fat accumulation in ducks by regulating the intestinal microbial composition and the metabolic pathways of amino acids that are linked to lipid metabolism.