The restriction of grazing duration does not compromise lamb meat colour and oxidative stability

Over 72 days, 33 lambs were fed: concentrates in stall (S), grass at pasture for 8 hours (8 h), or grass at pasture for 4 hours in the afternoon (4 h-PM). The 4 h-PM treatment did not affect the carcass yield compared to the 8 h treatment. Meat colour development after blooming was unaffected by the treatments. The 4 h-PM treatment increased the proportion of polyunsaturated fatty acids (PUFA; P < 0.0005) and of the highly peroxidizable fatty acids (HP-PUFA; P < 0.001) in meat compared to the 8 h treatment. The S treatment increased lipid oxidation (higher TBARS values) and impaired colour stability (higher H* values) of meat over storage compared to the 8 h and 4 h-PM treatments (P < 0.0005 and P = 0.003, respectively). No difference in meat oxidative stability was found between the 8 h and the 4 h-PM treatments. In conclusion, growing lambs can tolerate a restriction of grazing duration without detrimental effects on performances and meat oxidative stability.

► Reducing the grazing duration from 8 to 4 h did not impair lamb carcass yield.
► Reducing the grazing duration from 8 to 4 h did not affect lamb meat colour.
► Reducing the grazing duration increased the proportion of PUFA in meat.
► Reducing the grazing duration from 8 to 4 h did not affect meat oxidative stability.