Effects of Melengesterol Acetate, Selenium and Vitamin E Supplemental Feeding on Growth, Carcass and Longissimus Dorsi Muscle Traits in Hanwoo Cull Cows

Twenty four Hanwoo cull cows were assigned to 2 groups, control and melengerol acetate(MGA) + selenium supplement containing vitamin E(SeE), based on the parity(6.5 ± 1.7 birth) and body weight (493.17 ± 55.61 kg), and the experiment was conducted to establish the reasonable fattening method of cull cows for 240 days. Average daily body gains during 240 days were 0.51 kg and 0.63 kg in control and MGA + SeE, respectively(P<0.10). DDMI/ADG of MGA + SeE group improved compared to control group(P<0.05). Therefore, supplementation of MGA + SeE in concentrates may accelerate both of the growth rate and feed efficiency in Hanwoo cull cows. MQI from MGA + SeE was more developed based on the larger rib-eye area and thinner backfat thickness in carcass than that from control. Marbling score for MGA + SeE tended to increase compared to control. Dietary Se supplementation significantly affected muscle Se concentration in longissimus dorsi meat of MGA + SeE group(P<0.05). Similar results to Se were obtained from α-Tocoperol concentration. During 7 days of simulated retail display, accumulations of thiobarbituric acid reactive substances(TBARS) concentration in beef was greater(P<0.05) in control than in supplemented cows. These results supported the hypothesis that supplementation of MGA + SeE improve the growth performance and carcass grade both by the growth stimulating effect of MGA + SeE and by preventing the oxidation of the longissimus dorsi muscle in Hanwoo cull cows.