Carcass Ultrasound 101: Measures of muscle
By Patrick Wall, Director of Communications, The National CUP Lab
Farm & Ranch Guide
Undoubtedly, one of the more enjoyable eating experiences from the beef carcass is the ribeye steak.
Often referred to as the longissimus dorsi in research journals, this muscle gets the vast majority of the attention in genetic selection as well as at the restaurant. Ribeye Area (REA) is the sole measure of muscle in a purebred animal’s Expected Progeny Difference (EPD) profile, unless you include collaborative measures like % Retail Product, Yield Grade, or some Indexes (which use REA in the formula).
The absence of other muscle selectors is not for lack of trying. Researchers have simply been unsuccessful in finding an indicator of muscle that is either more accurate or more practical than REA. This creates a challenge for beef cattle breeders to use somewhat limited resources to make progress in red meat yield, not just REA.