The effects of diets containing two corn stubble levels and three non-hydrogenated lipids sources on fattening performance, carcase, and meat quality of male hair-lambs

Abstract

Research regarding the association of fatty acids (FA) with corn stubble in feedlot lambs is limited. FA dietary supplements can reduce the digestibility of neutral detergent fibre (NDF). However, it is not known if the NDF amount added with corn stubble and FA source in the diet can influence the content of polyunsaturated fatty acids (PUFA) and the conjugated linoleic acid (CLA), all of which are related to meat quality. In this study, 96 male-lambs (29 ± 4.9 kg) were assigned in two dietary NDF levels [25% (NDF-25) and 29% (NDF-29)] and four supplemental fat treatments [no supplemental (C), 3% CLA-60, 3% Safflower oil (SAF) and 3% linseed oil (LIN)] evaluated in a 2 × 4 factorial arrangement of treatments. Compared with CLA diets, diets supplemented with SAF and LIN contained more C18:2. Dietary forage level did not affect average daily gain, feed efficiency, or carcase characteristics (p = .56). With NDF-29 increased meat protein content (2%, p < .05). Meat chromatic b* values were greater (p = .02) with NDF-25. Control vs. supplemental lipids (SL) MUFA and PUFA increased in the muscle with SL. The endogenous level of CLA in muscle improved (p < .05) in the muscle with SL. Juiciness meat increased with both NDF levels and lipid supplements (p = .06). In conclusion, protein content and juiciness in the meat improve with NDF-29 (as corn stubble) on a diet. Similarly, SAF and LIN increase the content of PUFA and CLA in meat.