Effect of dietary starch level and its rumen degradability on lamb meat fatty acid composition

Forty lambs were fed one of four diets supplemented with a linseed and sunflower oil blend but differing in starch level (mid, approximate to 35 vs. high, approximate to 50%) and starch rumen degradability (mid, approximate to 70 vs. high, approximate to 80%). The effects of diet on growth, carcass traits and meat fatty acid (FA) composition, with emphasis on biohydrogenation intermediates were evaluated. Lambs stayed on trial for 5 weeks until slaughter. Treatment had no effect on animal performance and carcass traits. High-degradability diets decreased (P = 0.04) meat shear force compared with mid degradability diets. Lipid content of meat was unaffected by the diet. Mid-starch diets increased (P < 0.05) the saturated FA and cis-MUFA but decreased (P < 0.05) the trans-MUFA, particularly the t10-18:1, when compared with high-starch diets. The t11-18:1 (0.7% of total FA) and c9,t11-18:2 (<03%) remained low and the 18:3n-3 remained high (1.74%) and unaffected by diet. (C) 2016 Elsevier Ltd. All rights reserved.