Variation in the carcass characteristics of commercial british sheep with particular reference to overfatness.

Classification records for 136,000 sheep carcasses, a1 in 20 sample of those classified by the Meat and Livestock Commission in 1977, were used to examine the variation in weight, fatness and conformation of commercial British sheep. Overall mean carcass weight was 17·4 kg. Mean subcutaneous fat percentage in carcass (SF(e)) was estimated from the distribution of carcasses between fat classifications. Overall SF(e) was 11·3% and the regression of SF(e) on carcass weight was 0·44 %/kg. There were important differences in the characteristics of carcasses from abattoirs in different regions of the country: carcass weights ranged from 15·5 kg (Wales) to 23·4 kg (north of Scotland). Lambs slaughtered in the north of Scotland were also fattest (mean SF(e) = 13·9). The classification records were used together with results from MLC dissection studies to estimate excess fat production nationally. On the assumption that the consumer eats five parts lean to one part fat, excess carcass fat production from lambs and hoggets in 1977 was estimated to be 25,000 t.