Impact of Dietary Supplementation of Spice Extracts on Growth Performance, Nutrient Digestibility and Antioxidant Response in Broiler Chickens

SIMPLE SUMMARY: Capsaicin is a bioactive component that is obtained mainly from chili peppers and is a well-recognized antimicrobial agent, modulator of the immune response, and enhancer of nutrient digestibility, with a good potential to improve productivity in farm animals. This study explored the mechanism of action of a mixture of extracts containing capsaicin as the main component, together with black pepper and ginger, which was previously shown to exert positive effects on broiler chicken growth performance. Effects on nutrient digestibility, digestive enzyme activity, and plasma, jejunum and liver antioxidant response were examined. Results showed an enhancement of growth parameters, mainly in early stages; improvement of dry matter, crude protein and energy apparent ileal digestibility; and also effects on antioxidant enzyme activity in plasma and liver. ABSTRACT: This study aimed to investigate the effects of supplementing broiler chicken diets with an encapsulated product based on capsicum and other spice (black pepper and ginger) extracts on growth performance, nutrient digestibility, digestive enzyme activity and antioxidant response. To this end, 480 1-day-old male chicks were randomly assigned to two experimental treatments (12 pens/treatment; 20 birds/pen). Dietary treatments included a basal diet with no additives (CONTROL) and a basal diet supplemented with 250 ppm of the spice additive (SPICY; Lucta S.A., Spain). Supplementation of SPICY increased body weight (p < 0.05) compared with CONTROL at 7 d of age and improved (p < 0.01) ADG from 0 to 7 d of age. The apparent ileal digestibility of dry matter, gross energy and crude protein was higher (p < 0.05) in birds fed the SPICY diet compared with the CONTROL diet. Birds fed SPICY showed lower (p < 0.05) plasma catalase (CAT) activity, and the hepatic gene expression of CAT and Nrf2 was down-regulated (p < 0.05) compared with the CONTROL. In conclusion, the inclusion of 250 ppm of SPICY in broiler diets improved growth performance at 7 d of age and positively affected nutrient digestibility and antioxidant response.