Effect of feeding management from grass to concentrate feed on growth, carcass characteristics, meat quality and fatty acid profile of Timahdite lamb breed

•We compare carcass and meat quality of Timahdite lambs.•Lambs were raised under grass (PP), mixed (PC) and concentrate (CC) feeding systems.•Despite their low DMI, CC lambs presented better ADG and SLW than the grazing lambs.•PP and PC lambs showed better instrumental meat quality than CC lambs.•They had important percentage of PUFA and greater percentage of CLA than CC lambs.

Thirty male Timahdite lambs were divided into 3 groups (n = 10) and raised during 3 months under pasture (PP), pasture and concentrate (PC), and closed feeding systems with concentrate and hay (CC).Lambs were slaughtered at an average age of 276 ± 6 days and a mean live weight of 41 ± 1 kg. Carcass's conformation was studied by the measurements method.Instrumental meat quality and fatty acid profile in the semimembranous muscle were analyzed. Results showed that the feeding systems did not affect (P > 0.05) the lambs' average daily gain and the carcass quality, except the hind limb compactness index (P < 0.05), while they affected significantly the subcutaneous fat color and meat characteristics (P < 0.05). Lambs from PP and PC groups showed higher lightness and yellowness indexes (L* and b*) of subcutaneous fat, normal meat ultimate-pH, higher water holding capacity and greater meat lightness color compared to CC group (P < 0.05).The study of fatty acid profile showed that, compared to CC lambs, PP lambs had better percentage of polyunsaturated fatty acids (PUFA), especially n-3 fatty acids, with lower n-6/n-3 ratio apart from greater percentage of conjugated linoleic acid (P < 0.01).Based on these results, it is concluded that better quality meat was produced on open pastoral system of feeding with optimum PUFA.