The impact of dietary supplementation of Quercetagetin on growth, antioxidant capacity, and gut microbiota of diquat-challenged broilers

This experiment aimed to investigate the effects of Quercetagetin (QG) on the growth performance, antioxidant capacity, and cecal microbiota of broilers. Two hundred and forty 21-day-old WOD168 broilers with similar body weights were randomly divided into five groups of six replicates each with eight chickens. The control group was fed a basal diet composed of corn and soybean meal, while the experimental groups received basal diets supplemented with 0, 10, 20, and 40 mg/kg QG, along with intraperitoneal injection of 20 mg/kg body weight Diquat (DQ). The experiment lasted for 21 days. The results showed that: (1) QG significantly alleviated the decrease in average daily feed intake and average daily gain induced by Diquat, reduced the elevation of serum ACTH content, and significantly increased GH content (P < 0.05); (2) QG supplementation significantly mitigated the decrease in serum CAT activity and duodenal GSH-Px activity induced by Diquat (P < 0.05), as well as the increase in MDA content (P < 0.05); additionally, QG significantly increased the gene expression levels of GSH-Px, Nrf2, and Keap1 (P < 0.05); (3) Alpha and Beta diversity analysis revealed that QG supplementation significantly increased the cecal microbial OTUs and Chao1 index of broilers (P < 0.05). At the phylum level, compared with the Diquat group, the LQG group significantly decreased the relative abundance of Firmicutes (P < 0.05) and significantly increased the relative abundance of Bacteroidota (P < 0.05). At the genus level, compared with the CON group, the Diquat group significantly decreased the abundance of Lactobacillus and Alistipes (P < 0.05), while QG supplementation significantly alleviated the decrease in the abundance of Lactobacillus and Alistipes (P < 0.05). In conclusion, the addition of an appropriate amount (20 mg/kg) of QG to the diet can promote the growth of broilers, enhance antioxidant capacity, and improve intestinal health.