Influence of slaughter weight on the proximate composition and fatty acid profile of feedlot-fattened lamb meat - doi: 10.4025/actascitechnol.v32i3.4769

Abstract

The effects of slaughter weight (28, 32, 36, and 40 kg) on muscle composition and fatty acid profile were determined in an experiment using samples of the Longissimus dorsi (LD) of 20 ram lamb (½ Bergamacia and ½ Corriedale). Mean weight was 12.1 ± 1.05 kg at the beginning. Lambs were fed with a mixture of 30% corn silage, 35% soybean meal, 34% oat hay, and 1% vitamins and minerals, ad libitum. Samples of Longissimus dorsi muscle were analyzed for their content in moisture, ash, crude protein, total lipids, and fatty acid profile. Oleic acid (18:1n-9) was in greater concentration than other fatty acids in all samples investigated. The concentration of saturated fatty acids (SFA) increased (p < 0.05) with an increase in slaughter weight, while monounsaturated and polyunsaturated fatty acids (PUFA) decreased. Lambs slaughtered at either 28 or 36 kg had an n-6/n-3 ratio (2.9 and 2.85, respectively) close to the recommended for humans (4.0 maximum). The overall results showed that slaughtering lamb at 28 kg resulted in the best meat quality as shown by nutritional indexes for humans (PUFA/SFA and n-6/n-3 ratios) and concentrations of crude protein (16.02%) and total lipids (13.24%).