Coping heat stress by crushed fennel (Foeniculum vulgare) seeds in broilers: Growth, redox balance and humoral immune response

Abstract

The goal of this study was to determine how fennel seed supplementation affected broiler growth, carcass quality, antioxidant status, and antibody titre in heat stressed broilers. A total of 720 one day-old broiler chickens were weighed and assigned to 28 floor pens (25 broiler chickens per pen). The broiler chickens were housed in a thermoneutral (TN) environment and were exposed to heat stress (HS). For 23 h, the broiler chickens were kept under fluorescent lighting. For 35d, HS broiler chickens were fed a control diet and three levels of fennel seeds powder at rates of 15g/kg (Fen-15), 20 g/kg (Fen-20), and 25 g/kg (Fen-25). Overall feed intake, weight gain, and dressing % were considerably greater (P < 0.05) in Fen-25 and TN, but FCR was significantly reduced (P<0.01) in the same groups. When TN, Fen-20, and Fen-25 were compared to the control, malanodialdehyde (MDA), paraoxonase (PON1), and antibody titre against New Castle disease (ND) were considerably (P < 0.05) greater. Further, linear and quadratic response was for feed intake, weight gain, FCR, MDA, PON1 and ND titre. It was concluded that Fen-20 and Fen-25 increased broiler growth, carcass quality, antioxidant status, and immunological response under HS conditions.