Effect of supplementation with extract and on growth performance and intestinal health in broiler chickens.

Intestinal microbiota community is an important factor affecting the nutritional and health status of poultry, and its balance is crucial for improving the overall health of poultry. The study aimed to investigate the effect of dietary supplementation with extract (GUE), (Lac) and their combination (GL) on growth performance and intestinal health in broilers in an 84-day feeding experiment. Supplementary 0.1% GUE and 4.5×10 CFU/g Lac significantly increased average daily gain (ADG), and GL (0.1% GUE and 4.5×10 CFU/g Lac) increased ADG and average daily feed intake (ADFI), and decreased feed conversion rate (FCR) in broilers aged 29 to 84 d and 1 to 84 d. Dietary GUE, Lac and GL increased the superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activity and decreased Malondialdehyde (MDA) content in the jejunum mucosa of broilers, and increased secretory IgA (sIgA) content in broilers at 84 d. Moreover, GUE, Lac and GL increased cecal microbial richness and diversity, and modulated microbial community composition. Both GUE and Lac reduced the harmful bacteria , , and at 28 d and , , and at 84 d, while Lac and GL increased beneficial bacteria and at 28 d. Compared with individual supplementation, GL markedly increased the SOD activity and the sIgA content, and reduced and . In conclusion, GUE and as feed additives benefit growth performance and intestinal health, and their combined use shows an even more positive effect in broilers.