Fatty acid composition and physicochemical and sensory characteristics of meat from ewe lambs supplemented with zilpaterol hydrochloride and soybean oil

Abstract

The effects of supplementation of zilpaterol hydrochloride (ZH; 0 or 10 mg/lamb daily) and soybean oil (SBO; 0% or 6%) on carcass traits, body fat deposition, chemical, physicochemical, sensory quality, and fatty acid composition of the longissimus thoracis muscle (LTM) of ewe lambs were studied using a randomised complete design with a 2 × 2 factorial arrangement. After a 32-day feeding period, all ewes were slaughtered and LTM collected. Interactions between ZH × SBO were not observed (P > 0.05) for any of the variables evaluated. Feedlot performance was not modified (P > 0.05) by ZH and SBO supplementation. Biological yield and hot carcass weight were increased by ZH supplementation (P < 0.05). ZH and SBO supplementation did not alter body fat deposition (kidney, pelvic and heart, renal, thickness and intramuscular fat) and the empty bodyweight (P > 0.05). Meanwhile, feeding ZH decreased colour parameters (L*, a*, b* and CHROMA) (P < 0.05), but not others characteristics of LTM (P > 0.05). Sensory panelists observed an increase in appearance (P < 0.001) by ZH supplementation. Additionally, ZH decreased (P < 0.05) the content of C20:5n3 (eicosapentaenoic acid), C22:6n-3 (docosahexaenoic acid) and total omega-3 fatty acids, compared with the zero ZH group. Physicochemicals and sensory characteristics, and fatty acid composition of meat were not modified by SBO (P > 0.05). In conclusion, ZH supplementation to ewe lambs increased biological yield and hot carcass weight, without changes in body fat deposition and decreased eicosapentaenoic acid, docosahexaenoic acid and omega-3 contents and caused a decrease in colour of LTM. However, feeding SBO caused no changes in the carcass or meat quality traits and minimal changes in fatty acid composition of LTM.