Dietary supplementation with dihydroartemisinin improves the slaughter performance, serum biochemistry, and intestinal health of broiler chickens

The medicinal herb Artemisia annua L. has traditionally been used to promote human and animal health. One of the most important bioactive metabolites is dihydroartemisinin; however, its impact on intestinal health in broilers has not been sufficiently researched. The aim of this study was to investigate the effects of dihydroartemisinin on growth performance, slaughter performance, serum biochemistry, and intestinal health of AA broiler chickens. Four hundred broilers were randomly divided into five treatment groups, with eight replicates and ten chickens per replicate. The birds were fed a basal diet supplemented with 0, 5, 10, 20, or 40 mg/kg dihydroartemisinin for 42 consecutive days. The data were analyzed by one-way ANOVA and orthogonal polynomial contrast. Results showed that dihydroartemisinin supplementation at 10 mg/kg quadratically increased the average body weight, and supplementation at 10-20 mg/k quadratically increased the average daily gain from d 1-21. Dihydroartemisinin supplementation at 20 mg/kg quadratically increased the breast muscle rate and relative length of the jejunum (P < 0.05). Dihydroartemisinin supplementation at 5-40 mg/kg also quadratically increased the serum total protein, albumin, and IgG concentrations at d 42 (P < 0.05). Dihydroartemisinin supplementation at 5-10 mg/kg also quadratically increased the serum globulin concentrations (P < 0.05). Furthermore, dihydroartemisinin supplementation at 10-20 mg/kg quadratically improved villus length and the villus length to crypt depth ratio in both the jejunum and ileum, while reducing crypt depth and increasing the thickness of jejunal tunica muscularis (P < 0.05). Dihydroartemisinin supplementation at 10-20 mg/kg caused a linear and quadratic increase in the mRNA expression of claudin-1 in the jejunum (P < 0.05), an indicator of positive effects on intestinal tight junctions. Dihydroartemisinin supplementation at 10-20 mg/kg also linearly and quadratically increased the mRNA expression of mucin2 (MUC2) and toll-like receptor 4 in the jejunum (P < 0.05). Compared to the control group, dihydroartemisinin supplementation at 5, 20, and 40 mg/kg quadratically increased the mRNA expression of kruppel-like factor 4 (KLF4) in the jejunum (P < 0.05). In conclusion, dihydroartemisinin promoted slaughter performance, serum biochemistry, and intestinal health, including improvements to intestinal morphology and the mucus barrier through the induction of MUC2 and KLF4 genes expression.