Effects of dietary inclusion of Radix Bupleuri and Radix Astragali extracts on the performance, intestinal inflammatory cytokines expression, and hepatic antioxidant capacity in broilers exposed to high temperature

Abstract The Radix Bupleuri (RB) and Radix Astragali (RA) extracts have anti-inflammatory and antioxidant functions in humans. To determine whether RB and RA extracts had these functions in chronic heat-stressed broilers, 560 15-day-old male broilers were assigned to 7 groups of 8 replicates each (10 birds per replicate), and were under following conditions: 36 °C for 8 h (09:00-17:00) and 30 °C for the remaining time. The broilers were fed the basal diet (control) or the basal diet supplemented with 200 or 400 mg/kg RB extracts (RB200 or RB400), 600 or 800 mg/kg RA extracts (RA600 or RA800), RB200 plus RA800 (RB200-RA800), or RB400 plus RA600 (RB400-RA600) for 28 days. The RB extracts contained 40.1 mg saikosaponins/g, and RA extracts contained 80.0 mg Astragalus polysaccharide/g. Dietary inclusion of RB or/and RA extracts increased (P