Influence of stall finishing duration of Italian Merino lambs raised on pasture on intramuscular fatty acid composition

Forty male Italian Merino lambs were used to study the effects of four feeding systems on muscle fatty acids composition: S group—ten lambs were kept indoors, and fed with concentrate for all experimental period (89 days); P group—ten lambs were allowed to graze a pasture for all experimental period; PS37 group—ten lambs were allowed to graze a pasture for 52 days and shifted indoor, fed with concentrate, 37 days before slaughtered; PS14 group, where 10 lambs were fed on pasture for 75 days and shifted indoor, fed with concentrate, 14 days before slaughtered. Grazing lowered the levels of C12:0, C14:0, C16:0 and n-6 PUFA and increased n-3 PUFA and CLA isomer compared to concentrate feeding. After a short period of indoor finishing with concentrate, the fatty acid characteristics of the meat retain a part of the benefits occurring from grazing, while a longer period seems to erase almost all the benefits from grazing. ► The objective of the trial is to evaluate the effect of concentrate after pasture on meat fatty acids of lambs. ► The study was carried out on 40 lambs divided in 4 groups: P, pasture, S, concentrate, PS37 and PS14. ► Meat from PS14 lambs retain part of the benefits occurring from grazing but not meat from PS37 lambs.