Ultrasound Fat and Muscle Measurements of Live Lambs as a Predictor of Carcass Fat and Muscle Measurements and Changes in Ultrasound Rib Eye Area and Fat Thickness as Lambs Grow

Muscular and lean market lambs grow more efficiently and produce a meat product more preferred by the consumer compared to poorly muscled and fat lambs. Therefore, a case can be made for selection of breeding stock, especially within the terminal sire breeds like Suffolk and Hampshire, for desired carcass composition. Since breeding stock cannot be slaughtered in order to obtain carcass measurements, carcass traits must be estimated indirectly. Some well-trained livestock evaluators can do a reasonably accurate job of estimating carcass traits from a visual inspection of an animal. However, an objective measurement of carcass traits in live animals would be of great benefit to the entire sheep industry. Ultrasound technology has been used quite effectively in the swine industry and to a lesser extent in the beef cattle industry for measurement of carcass traits in live animals. Relatively little use has been made of ultrasound technology in the sheep industry.