The Relationship of Live and Carcass Measurements to Carcass Meatiness and the Influence of Sex and Sire on Carcass Traits in Lambs

The changing demands of the consumer have caused quite an influence on our breeding, feeding and management programs. The consumer is better educated and spends more time selecting which cut or cuts of meat to buy. The desire of the consumer to purchase leaner cuts and cuts with more eye appeal has influenced producers to select parent stock with more desirable meat qualities, and animal scientists to strive to find measures which producers could use in their selection programs in order to produce more red meat and less fat. The popularity of other meats has increased and the per capita consumption of lamb has decreased. Thus we need better consumer appeal, less fat and more lean in order to compete with other meats. The improvement of meatiness and carcass desirability of lamb is of great concern. Research in the past has dealt more with carcass traits than with live traits as a means of selecting the superior meat animal. The use of carcass traits requires the slaughtering of the animal for an accurate appraisal of the carcass. Faster progress could be made if certain live animal characteristics would reflect carcass meatiness and could be identified for selection purposes. Many researchers have used a combination of several measurements rather than a single measurement as a live meatiness predictor. Percent yield, percentage of wholesale cuts, edible portion, carcass weight, percentage of separable lean, area of loin eye, fat covering and specific gravity determinations are all used as indices or carcass merit. Information and techniques for accurate evaluation of live animals are readily apparent in every packing plant. For many years subjective live scores for the entire animal or component parts of the animal were used as predictors of both slaughter and breeding value; however, these have recently been shown to be of questionable predictive value. The lack of live measurements which are highly correlated to the carcass presents a problem for the breeder and feeder. If live animal measurements could predict carcass characteristics accurately, then satisfactory selection of breeding animals for lamb carcass improvement could be carried out. Sheep producer organizations and some of the breed associations have been advocating ram production testing programs to improve the quality of lamb carcasses. More research is needed to study live animal appraisal as a means of predicting meatiness in the carcass. This research was conducted to further study the relationship of live measurement or measurements which could be used to predict carcass merit