Effects of Ruminally Protected Amino Acid-enriched Fatty Acids on Growth Performance and Carcass Characteristics of Fattening Hanwoo Cows

This study was conducted to determine the effects of ruminally protected amino acid-enriched fatty acids (RPAAFA) on bodyweight gain, feed intake and carcass characteristics of fattening Hanwoo cows. Twenty eight Hanwoo cows, 6.0±1.7 years old andweighing an average of 463.2±77.6 kg, were used for 4 months. Animals were fed a basal diet supplemented with RPAAFA at 0g (control) and 100 g (treatment), respectively. Average daily gain, dry matter intake and feed conversion ratio were not differentamong the control and treatment. The supplementation of RPAAFA did not affect carcass weight and rib eye areas. Quality gradescore (1 ++ ,1 + and 1) for treatment was higher in RPAAFA supplemented group compared with the control, whereas no differencesappeared in meat color, fat color, texture and maturity. Thus present results indicate that supplementation of RPAAFA may berecommended for producing high quality beef from fattening Hanwoo cows.( Key words : Hanwoo cows, Ruminally protected amino acid-enriched fatty acids, Carcass characteristics, Beef fattening)