Development of intramuscular fat in prime lambs, young sheep and beef cattle

Intramuscular fat (%) increases relatively slowly with carcase fatness (and weight) until a carcase fatness of about 35% is reached. This level of fatness is not compatible with profitable production systems for prime lambs and so there is no point in over conditioning lambs (beyond the minimum desirable fat score 2) in an effort to achieve eating quality benefits. Premiums paid for marbled beef in some markets allow production systems with fatter cattle to be profitable. Finally genetic selection for intramuscular fat can powerfully shift fat distribution toward the intramuscular site.