Effect of Niacin on Growth Performance, Intestinal Morphology, Mucosal Immunity and Microbiota Composition in Weaned Piglets

Abstract

This study aimed to investigate the effects of niacin on growth performance, intestinal morphology, intestinal mucosal immunity, and colonic microbiota in weaned piglets. A total of 96 weaned piglets (Duroc × (Landrace × Yorkshire), 21-d old, 6.65 ± 0.02 kg body weight (BW)) were randomly allocated into 3 treatment groups (8 replicate pens per treatment, each pen containing 4 males; n = 32/treatment) for 14 d. Piglets were fed a control diet (CON) or the CON diet supplemented with 20.4 mg/kg niacin (NA) or an antagonist for the niacin receptor GPR109A (MPN). The results showed that NA or MPN had no effect on ADG, ADFI, G/F or diarrhea incidence compared with the CON diet. However, compared with piglets in the NA group, piglets in the MPN group had lower ADG (p = 0.042) and G/F (p = 0.055). In comparison with the control and MPN group, niacin supplementation increased the villus height and the ratio of villus height to crypt depth (p < 0.05), while decreasing the crypt depth in the duodenum (p < 0.05). Proteomics analysis of cytokines showed that niacin supplementation increased the expression of duodenal transforming growth factor-β (TGF-β), jejunal interleukin-10 (IL-10) and ileal interleukin-6 (IL-6) (p < 0.05), and reduced the expression of ileal interleukin-8 (IL-8) (p < 0.05) compared with the control diet. Piglets in the MPN group had significantly increased expression of ileal IL-6, and jejunal IL-8 and interleukin-1β (IL-1β) (p < 0.05) compared with those in the control group. Piglets in the MPN group had lower jejunal IL-10 level and higher jejunal IL-8 level than those in the NA group (p < 0.05). The mRNA abundance of duodenal IL-8 and ileal granulocyte-macrophage colony-stimulating factor (GM-CSF) genes were increased (p < 0.05), and that of ileal IL-10 transcript was decreased (p < 0.05) in the MPN group compared with both the control and NA groups. Additionally, niacin increased the relative abundance of Dorea in the colon as compared with the control and MPN group (p < 0.05), while decreasing that of Peptococcus compared with the control group (p < 0.05) and increasing that of Lactobacillus compared with MPN supplementation (p < 0.05). Collectively, the results indicated that niacin supplementation efficiently ensured intestinal morphology and attenuated intestinal inflammation of weaned piglets. The protective effects of niacin on gut health may be associated with increased Lactobacillus and Dorea abundance and butyrate content and decreased abundances of Peptococcus.

Effect of different dosages of sodium butyrate and niacin on growth, faecal microbiota and Vitamin B metabolism in weaned piglets

“…The sodium butyrate and niacin diet can alleviate diarrhoea symptoms and increase growth performance in pigs (Liu et al, 2021; Sun et al, 2020). In our study, sodium butyrate and niacin were reported to be harmless to the body, even at high doses.…”

“…During the weaning period, weaning causes reductions in intestinal immunity and Vitamin B metabolism, resulting in susceptibility to diarrhoea and growth obstruction (Hu et al, 2013; Smith et al, 2010). Various studies have documented that butyric acid and niacin are often used in swine production to improve the intestinal health and growth performance of piglets (Feng et al, 2018; Liu et al, 2021). Butyric acid is involved in multiple physiological processes of primary importance for growth, such as immune modulation, Vitamin B metabolism and intestinal microbiota composition (Chen et al, 2019; Leonel & Alvarez‐Leite, 2012).…”

Quercetin Reduces Inflammation and Protects Gut Microbiota in Broilers

“…The quantitative changes in some specific bacteria in the present study were supported by previous studies. Studies have pointed out that the abundance levels of Halomonas , Peptococcus , and Rubrobacter can be associated with intestinal inflammation, and are increased when intestinal inflammation occurs [ 36 , 37 , 38 ]. Streptomyces and Micromonospora , as members of Actinobacteria , have been shown to have anti-inflammatory and antioxidant effects [ 39 , 40 , 41 ].…”

Niacin Improves Intestinal Health through Up-Regulation of AQPs Expression Induced by GPR109A

“…Collectively, these findings indicated that AQPs may be potential targets for attenuation of diarrhea. As a common feed additive in pig farming, niacin has been shown to improve the intestinal health of weaned piglets [ 22 , 23 ]. However, the relationship between niacin-mediated alleviation of the weaning stress-induced diarrhea and the changes in AQPs expression, and the underlying mechanism needs further exploration.…”

“…Recent studies have shown that GPR109 is expressed in intestinal epithelial cells and has a role in regulating microbial metabolism, inhibiting colonic inflammation, and maintaining the integrity of the intestinal barrier [ 25 , 26 ]. Furthermore, supplements with niacin can increase the relative abundance of probiotics in the colon, and alleviate the inflammatory response in the small intestine via GPR109A [ 23 ]. However, limited information regarding whether niacin directly regulates the expression of AQPs in weaned piglets via GPR109A.…”