The Milk Marketing Board beef shape (BS) score for a sire is derived from the beef conformation assessments made during the routine inspection of his first lactation daughters in the Dairy Progeny Testing Scheme. The trial compared the scores for seven Friesian/Holstein sires with the beef characteristics of their steer progeny. Two groups of cattle, 189 in total, all out of Friesian dams, were used in the trial. The dams were assessed for BS. The cattle were reared on a standard grass/cereal system designed to achieve an overall target live-weight gain of 0·85 kg/day and slaughtered at 530 kg live weight. An assessment of BS was made at seven points during the lifetime of each animal. Carcass classification and assessment together with dissection of the shin joint was undertaken by the Meat and Livestock Commission. In addition to this, 40 carcasses representing high and low BS scores were taken for full dissection of the left side.

The BS score of the dam had no significant effect on the score of the calf at any point during its life. The relationship between the sire BS score and the calf score did not become significant until the calf was 12 months old (P < 0·01) and was still significant immediately prior to the slaughter of the calf (P < 0·05). Carcass conformation scores showed highly significant progeny group differences (P < 0·001). The regression of the sire progeny group means, corrected for estimated proportion of subcutaneous fat, on the sire BS scores was significant (P < 0·001). The carcasses in the high BS score group had a significantly greater weight of lean than those in the low BS score group.

The trial compared 50 purebred Canadian Holstein and 46 British Friesian steers. The cattle were reared on a grass/cereal system designed to achieve an overall target live-weight gain of 0·82 kg per day from weaning to slaughter at 18 months of age. The cattle, born i n September 1973, grazed during the summer of 1974 and were slaughtered out of yards from January to July 1975. Equal numbers of each breed were allocated at random to three slaughter weights (477, 500 and 523 kg live weight). The Meat and Livestock Commission measured and classified all carcasses. In addition, a sample was cut according to commercial specifications. There were no significant differences in slaughter age or live-weight gain between the breeds. A significant difference (P < 0·05) in killing-out percentage was found in favour of the British Friesian as was a small (4%) but highly significant difference (P < 0·001) in carcass gain.

The Canadian Holstein carcasses were considerably longer (P < 0·001) with less eye-muscle area (P < 0·001). The British Friesian carcasses contained 0·7% more saleable meat (P < 0·001) and 1% less bone (P < 0·01). There were no significant differences in fat trim. There were large differences in live appearance and carcass classifications, the British Friesians being of superior beef conformation.