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The relationships between body fat depots and body condition score (BCS) were determined in 52 adult Rasa Aragonesa ewes aged 10 (s.d. 2) years and ranging in BCS from 1·5 to 4·5. BCS of each ewe was assessed by three people, the repeatability within individuals being 90% and between individuals 80%. The ewes were weighed before slaughter. After slaughter the omental, mesenteric, kidney and pelvic fat were separated and weighed. The fat of the left side of the carcass was separated into subcutaneous and intermuscular depots. The relationship between live weight and BCS was semilogarithmic and those between fat depots and BCS were logarithmic. Regression analysis was also used to describe the relationships between the various fat depots and BCS or live weight. Of the variation in total fat weight, proportionately 0·90 was accounted for by variations in BCS, while 0·84 was accounted for by variations in live weight. For individual fat depots proportionately 0·86 to 0·90 of the variation was accounted for by variation in BCS and 0·69 to 0·79 by variation in live weight. BCS was a better predictor than live weight of the weight of both total body fat and the individual fat depots.A curvilinear regression between BCS and live weight showed that the increases in live weight for a unit change in BCS was 7, 10, 12 and 16 kg for each one point increase in BCS from 1 to 5 respectively.The tail fat depot (tail fatness score) was assessed in the same ewes by score on a three-point scale. Of the variation in the weight of individual fat depots, proportionately 0·79 to 0·86 was accounted for by variation in tail fatness score. Thus the tail fatness score could be used as an additional method of assessing body condition in the Aragonesa breed.

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Carcasses of 129 steers from ten different sire breeds including dairy breeds, traditional British beef breeds and continental breeds were classified according to the shape of the tuber ischii-tuber calcis profiles of their hindquarter using a 7-point conformation scale. Conformation class was found to be related to both commercial and dissected carcass composition as well as the dimensions of seven hindquarter muscles. At the same carcass weight and fatness the muscle content of the hindquarter increased by 0-56 kg and the bone decreased by 0-13 kg linearly per unit increase in conformation class; the corresponding increase in the muscle-to-bone ratio was 0-07. The general trend for muscle dimensions was that the convex carcasses had shorter and thicker muscles than concave carcasses. A simple method of assessing carcass conformation based on three fundamental profiles of the hindquarter, from which the seven conformation classes were derived, permitted the grouping of carcasses according to their composition. Nevertheless the accuracy of the method may be improved with further investigation.

The lumbar joint, which is handled to assess body condition scores, was taken from 52 adult Rasa Aragonesa ewes with body condition scores between 1·5 and 4·5 and dissected into muscle, bone, subcutaneous and intermuscular fat. The subcutaneous fat in the lumbar joint was highly correlated with total fat in the body (r=0·97), confirming the value of this region for assessing body condition in Rasa Aragonesa ewes.