Effects of supplemental β-carotene on growth performance, immune function and intestinal mucin in weaned piglets
Abstract Background Weaning stress causes intestinal immune system disorders. β-carotene displays anti-inflammatory,which can prevent the development of inflammatory diseases. The aim of this study was to determine the effect of supplemental β-carotene on growth performance, immune function and intestinal mucin in weaned piglets.Results A total of 45 piglets with the average body weight of 4.62 ± 0.06 kg (14 d of age) were randomly assigned to 3 treatments with 5 replicate pens per treatment and 3 pigs per pen and weaned at 21 d. The control group (CG) fed the basal diets from 14 d to 24 d of age. The low-dose group (LG) and the high-dose group (HG) fed the basal diets supplemented with 40 or 80 mg/kg β-carotene from 14 d to 24 d of age, respectively. Compared with the CG, t he average daily gain (ADG) and average daily feed intake (ADFI) of piglets in the HG were increased (p<0.05). And the IgA and IL-10 levels in serum in the HG were also higher than those in the CG (p<0.05). The IgM, TNF-α and IL-6 levels in serum in the β-carotene groups were lower than those in the CG (p<0.05). Periodic Acid-Schiff stain results showed that the content of mucopolysaccharide and the number of goblet cells in the intestine in the β-carotene groups were more than those in the CG (p<0.05). The results of immunofluorescence showed that the expression of MUC1 in the intestine in the β-carotene groups was lower than that in the CG (p<0.05). And the expression of mucin1 mRNA in the intestine in the β-carotene groups was also lower than that in the CG (p<0.05). However, compared with the CG, the expression of mucin2 mRNA in the intestine in the HG was increased (p<0.05).Conclusion Supplemental β-carotene could improve growth performance, immune function and intestinal mucin in weaned piglets. It is suspected that our pre-protection of β-carotene in weaned piglets may help weaned piglets safely through the weaning period.