Dietary influences on lutein pigments and carcass fat quality in wethers of different maturity types

The aim of this research was to study the effect of high-maize diets and pe lleting on the accumulation of lutein pigments and appearance of the subcut aneous fat in Dorper and SA Mutton Merino wethers. High and medium energy m aize diets were fed to Dorper and SA Mutton Merino wethers from an initial live weight of ca. 21 kg to a target weight of 43 kg. Fat colour and firmne ss were evaluated subjectively on a 5-point scale. Samples of the subcutane ous fat and feed were collected for fatty acid and lutein analyses. Loin sa mples (L1-L6) were oven-roasted and fat characteristics evaluated by a trai ned sensory panel. The concentrations of lutein pigments and total long-cha in fatty acids were influenced mainly by the fattening period (p<0.05) and pelleting of the diets (p<0.05). Lutein concentrations increased during lon ger fattening periods and resulted in lower colour scores for subcutaneous fat. Neither breed nor the maize content of the diet significantly affected the concentration of lutein in the subcutaneous fat. Lutein concentrations resulted in lower subjective colour scores (p<0.05) and improved the aroma of lamb during carving (p<0.05). The present results suggest that the 'una cceptable' lutein pigments contribute to the typical aroma of lamb.