After studying sources of variation

After studying sources of variation in tenderness of youthful, grain-fed beef , we, and others, have found that marbling will account for at most 15% of the variation in aged beef tenderness. Other carcass traits, proposed to be related to beef tenderness, such as skeletal and lean maturity, fat thickness, carcass weight, and lean color, texture, and firmness, are even more weakly related to aged beef tenderness. Concomitantly, our data indicate live animal performance traits such as slaughter weight, weight per day of age, average daily gain, and time-on-feed will not account for a significant portion of the variation in aged beef tenderness. The one historical trait that will consistently explain a large percentage of the variation in aged beef tenderness is the percentage of Bos indicus inheritance in the cattle. Numerous experiments have demonstrated that the frequency of unacceptably tough meat is greater for cattle possessing high levels of Bos indicus inheritance . However, most research indicates that cattle containing 25% or less Bos indicus inheritance are similar to their Bos taurus counterparts in palatability . Thus, if one adheres to sound crossbreeding principles, the production advantages of Bos indicus crossbred cattle may be reaped without compromising product quality.