Productivity and meat quality of broiler chickens fed a diet supplemented with ethanolic propolis extract

The aim of this study was to evaluate the effects of adding different doses of ethanolic propolis extract (EPE) to the diet of broiler chickens on production parameters, physicochemical properties, nutritional value, fatty acid profile and antioxidant capacity of the meat. A total of 200 one-day-old chickens of the Ross 308 line were randomly divided into 4 treatment groups with 5 replicates each: P0 (control), P150 (150 mg propolis per kg feed), P300 (300 mg propolis per kg feed) and P450 (450 mg propolis per kg feed). The results show that the addition of 150 mg/kg EPE significantly decreases feed conversion ratio (FCR) in the finisher phase and throughout the entire growth period, while the weight of carcass pieces increases by 17%. No differences were found between the treatments with regard to the physicochemical properties and nutritional value of the meat (P > 0.05), but there were differences in the fatty acid profile (P < 0.05). The meat from birds treated with P150 had the highest concentration of unsaturated fatty acids (UFA). The antioxidant capacity in the meat of chickens fed with propolis supplemented feed showed greater stability than the meat of the control group, with the highest values observed in the P450 treatment, which maintained a high level of antioxidant capacity during storage. The L* values for brightness exhibited differences between treatments, but not over time. The variable a* showed significant differences between the treatments and the cooling time. The variable b* was only different (P < 0.05) between the treatments on days 1, 3 and 5 and only the P450 treatment showed differences over time. Considering the effects of different doses of EPE on the aforementioned variables, an EPE dose of 150 mg/kg diet is determined to be the recommended one.