Effects of Adding Ethanol Extract of Propolis and Cumin Essential Oil to Diet on the Performance, Blood Parameters, Immune Response and Carcass Traits of Broiler Chicks

This study was conducted to determine the effects of adding ethanol extract of propolis (EEP) and cumin essential oil (CEO) to diets of broiler chicks on the performance, blood parameters, immune response and carcass traits. A total of 240 day-old Ross-308 broiler chicks were randomly allocated to four treatments with six replicates and 10 birds in each replicate in a completely randomized design. Each of four isocaloric and iso-nitrogenous corn-soybean-based experimental diets including control, diet with 0.2 g/kg EEP, diet with 0.8 g/kg CEO and diet with 0.2 EEP g/kg as well as 0.8 g/kg CEO were offered to the birds during a 6-week trial period. Body weight (BW), body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR) were determined throughout starter and grower periods (1-21 and 22-42 days of age, respectively). Plasma levels of albumin, cholesterol, high density lipoprotein (HDL), low density lipoprotein (LDL), triacylglyceride (TG), uric acid, glucose and leukocyte profile were determined on day 42 of age. At the end of the experimental period, carcass traits were also determined. Diet inclusion of EEP and / or CEO significantly improved BW, BWG and FCR. The birds fed diet containing EEP at 0.2 g/kg had significantly lower plasma concentration of glucose compared to the control group. The use of EEP or CEO significantly decreased plasma concentration of cholesterol compared to the control group. The use of EEP or CEO also increased plasma concentration of albumin compared to the control group. Diet inclusion of EEP and/or CEO did not significantly influence the antibody titters against Newcastles vaccine at 31 and 41 days of age, H/L ratio and also carcass characteristics. Results of this study showed that EEP and CEO can be used in diets of broiler chickens at 0.2 g/kg and 0.8 g/kg, respectively with positive effects on performance and blood parameters.