Effect of dietary addition of phenolic compounds from propolis on growth performance, carcass traits, and meat fatty acid profile of feedlot beef cattle

Twenty-four male Nellore steers (445 +/- 31 kg initial body weight) were used to evaluate the effects of different doses of phenolic compounds from a propolis-based product (PBP) on growth performance, carcass traits, and meat fatty acid (FA) profile. The total mixed ration consisted of 470 g kg(-1) corn silage and 530 g kg(-1) concentrate (dry matter [DM] basis), which were randomly assigned to one of three treatments: control (CON, without phenolic compounds from the propolis extract), PBP1 (225 mg of phenolic compounds g(-1) of propolis dry extract), and PBP2 (300 mg of phenolic compounds g(-1) of propolis dry extract). The animals were fed in a feedlot for 84 days and presented an average final body weight (FBW) of 542 kg. Dietary addition of phenolic compounds had no overall effect on growth performance. Mean values for dry matter intake, average daily gain and feed conversion ratio were 9.99 kg d(-1), 1.14 kg d(-1) and 8.82 kg DM kg gain(-1), respectively. Hot carcass weight and hot carcass yield had average values of 308 kg and 56.8%, respectively. In addition, carcass traits did not change after PBPs were added to the diet, except for the ribeye area, which was higher for PBP2 (21.5 cm(2) 100 kg(-1)) than for PBP1 (18.6 cm2 100 kg(-1)). Dietary addition of PBPs maintained redness better than the controls after 9 days in the refrigerator; no major changes were observed in the meat FA profile after the addition of PBPs to the diet. These results suggest that phenolic compounds present in propolis (300 mg g(-1)) have positive effects on meat color and improve the sensory quality of meat.