Rendimentos de carcaça, composição tecidual e musculosidade da perna de cordeiros alimentados com silagem de milho ou cana-de-açúcar em dois níveis de concentrado

Abstract

The effects of roughage:concentrate ratio and type of roughage were evaluated on the carcass yield and commercial cuts, and tissue composition and leg muscularity of 32 Ile de France lambs finished in feedlot and fed corn silage or sugar cane in two roughage:concentrate ratios: 60:40 or 40:60. The lambs were slaughtered with 32kg of body weight and the weight and yield of hot carcass (WHC and YHC) were determined. After refrigerated for 24h in cold camera, the weight and yield of cold carcass (WCC and YCC), real yield, and weight loss for cooling were obtained. The carcass was divided in five commercial cuts (shoulder, loin, leg, ribs, and neck), and the leg was dissected on muscle, bone, and fat, and the relations muscle:bone and muscle:fat and also the leg muscularity index were calculated. The lambs fed corn silage showed higher WHC (16.05kg), WCC (15.61kg), YHC (50.42%), and YCC (49.03%). The loin yield was lower in lambs fed sugar cane (9.11%). The sugar cane and corn silage in this two roughage:concentrate ratios did not affect the proportions of muscle, bone, and fat, and leg muscularity. Therefore, they can be used in diets for animals without reducing the proportions of these tissues, that are related to meat quality.