Effects of dose and administration form of rosemary essential oils on meat quality and fatty acid profile of lamb

The effects of the dose rates and administration form of Rosemary essential oils (REO) on lambs' meat quality were investigated. Thirty two Barbarine lambs were allotted to 4 homogeneous groups and fed oat-hay ad libitum with 500 g of concentrate. Rosemary oils were orally administrated in a dose of 0.3 and 0.6 ml/day to lambs of O-R1 and O-R2 groups, respectively. It was mixed to the concentrate in an equivalent dose of 0.3 ml/day for the Mix-R1 group, while the control group (C) did not receive REO. The administration of REO has not improved the daily individual hay intake (P > 0.05) which averaged 652 g dry matter (DM). Similarly, neither the presence of REO (Cst 1) nor the dose (Cst 2) or the incorporation form (Cst 3) did affect lambs' growth performances (P > 0.05); animals gained 6.7 kg of weight at the end of the experiment. Meat color parameters were not affected by REO administration (P > 0.05). However, the sensorial attributes (flavor and acceptability) were higher for REO groups than the Control one (P < 0.05). The sum of polyunsaturated Fatty acids (PUFA) was affected by REO administration being higher in the meat of O-R2 lambs (Cst 2 = 0.001). Similarly, the percentage of omega 6 (PUFA n-6), the PUFA/saturated fatty acids (SFA), and n-6/n-3 ratios increased with the oral administration of 0.6 ml of REO (Cst 2; P < 0.05).The oral administration of 0.6 ml REO could improve lamb's meat quality.