The experimentcarried out in aiming to evaluate the tissue and chemical composition of longissimusdorsi muscle of Suffolk lambs fed on creep feeding system with ration containing0.0, 6.60, 13.20 and 19.80% of sunflower seed. At kidding, the lambs were identified,weighed and randomly distributed to paddocks composing four replicates per ration,totaling 16 lambs. The rations contained 2.65, 2.78, 2.89 or 2.93 Mcal/kg ofME and 18.38, 18.75, 19.98 and 21.18% of CP and were ad libitum fed to the lambs.The lambs were weighed every 14 days and kept with the ewe until they reachthe pre-established slaughter body weight (28 kg). The carcasses were chillingin cold chamber at 5°C for 24 hours, and then were split into seven anatomicalregions for collection of the left and right loins and obtention of the variables:measures of L. Dorsi muscle, weight of the loin components (muscle, bone andfat); chemical composition and profile of fatty acids of muscle, bone and fat.The sunflower seed influenced total loin weight, muscle and connective tissueweights and connective tissue yield. The increase in sunflower seed percentagein the diet decreased the amount of lauric acid and palmitic (saturated), andincreased oleic and linoleic acids (unsaturated). The nutritional quality ofmeat of lamb improves with increased use of sunflower seed in the diet.
