The relative rate of increase in the carcass and its tissues with increasing empty body weight (EBW) or carcass weight respectively, was studied in male sheep from the Dorset Horn (29), Hampshire (21) and Sudan Desert sheep (31). The rate at which the carcass, muscle and bone increased in weight was the same in all breeds but the Desert sheep deposited fat at a slower rate than the other 2 breeds. At an equally adjusted EBW the Desert sheep had lighter carcasses than the Dorset Horn or Hampshire sheep. Desert sheep had more bone than the other 2 breeds at an equally adjusted cold carcass weight or muscle plus bone weight. At an equally adjusted total carcass fat weight the Desert sheep had significant (P < 0.01) more intermuscular and internal fat but less subcutaneous fat than the other 2 breeds. Future improvement plans of the Desert sheep may be directed towards reducing bone and increasing muscle content of the carcass.