Higher niacin intakes improve the lean meat rate of Ningxiang pigs by regulating lipid metabolism and gut microbiota

Abstract

As one of the local pig breeds in China with a high fat rate, improving the lean meat rate of Ningxiang pigs through nutritional intervention is an urgent issue to be solved. As an important feed additive, niacin plays an important role in lipid metabolism. The purpose of this study was to investigate the regulation and mechanism of niacin on fat deposition in Ningxiang pigs. Thirty-four Ningxiang pigs (53.34 ± 2.78 kg) were randomly divided into two groups with five replicates each, with three to four Ningxiang pigs per replicate. The control group was fed a basal diet (contained 22 mg/kg niacin), and the experimental group was fed the same diet supplemented with an additional 100 mg/kg of niacin. The experimental period lasted 60 days. One Ningxiang pig was selected for slaughter sampling for each replicate. This study found that lean meat percentage of Ningxiang pigs in the experimental group was significantly increased (P < 0.05), accompanied by a significant decrease in fat percentage (P < 0.05). 16S rRNA sequencing analysis found an abundance of Streptococcus in the experimental group (P < 0.05), along with significantly decreased levels of Lactobacillus (P < 0.05). The changes in some OTUs belonging to Firmicutes, Bacteroidota, and Actinobacteriota were closely related to the changes in the fat rate and lean meat rate of Ningxiang pigs (P < 0.05). LC–MS metabolomics analysis found that about 43.75% of the differential metabolites were related to lipids and lipid-like molecules in the liver (P < 0.05). Spearman's correlation analysis showed correlations between the carcass traits, microbiota, and liver metabolites. In conclusion, niacin improves lean meat percentage and reduces fat deposition by regulating lipid metabolism and gut microbiota composition in Ningxiang pigs.

Metagenomic comparison of intestinal microbiota between normal and liver fibrotic rhesus macaques (Macaca mulatta)

“…MG had significantly more Campilobacterota than MN, while the Firmicutes level was significantly lower, consistent with the findings of Mainz et al 31 , who observed similar changes in a mouse model of alcoholic liver disease. Wang et al 32 also found that Firmicutes and Actinobacteriota were associated with changes in adiposity and leanness in pigs, suggesting a possible link between liver fibrosis development and fat and alcohol-metabolizing microbiota in vivo. At the genus level, the dominant genera in the intestinal microbiota of MG and MN were Prevotella , Lactobacillus , Treponema , Rikenellaceae_RC9_gut_group , and Eubacterium_coprostanoligenes_group .…”

Dietary succinate reduces fat deposition through gut microbiota and lipid metabolism in broilers

“…A 100 mg sample was accurately measured, ground, and added to the extraction solution at 4℃ for metabolite extraction, followed by centrifugation of the supernatant metabolite solvent for liquid mass spectrometry ( LC-MS ) detection. The procedures were the same as that described in the previous study ( Wang, et al, 2022b ).…”