A meta-analysis of the effect of pasture access on the lipid content and fatty acid composition of lamb meat

•Effect of pasture on lipid and fatty acids in lamb is evaluated by meta-analysis.•Access to pasture tends to decrease the fat content in lamb but increased SFA.•The contents of MUFA and n-6 PUFA are decreased in pastured lambs.•Pasture increases the content of n-3 PUFA and decreases the ratio n-6/n-3 in lamb.•Results suggest that grazing can be recommended to improve meat dietetic quality.

A meta-analysis on the influence of the pasture on the lipid content and fatty acid profile in lamb meat was conducted. A total of 20 studies were selected and data on total lipid content, saturated, mono- and polyunsaturated fatty acids in lamb meat were extracted for two population groups, indoors, and pastured. Due to the high between-study heterogeneity, separate random-effects models were applied to the raw mean difference (effect size parameterization) for each of the outcomes. The results of the meta-analysis pointed that access to pasture tended to decrease the fat content in lamb, while increasing the saturated fatty acids (P < 0.05). The amounts of monounsaturated and n-6 polyunsaturated fatty acids were decreased (P < 0.05). On the other hand, grazing led to substantial increase in the content of n-3 polyunsaturated fatty acids, and decrease (P < 0.01) of the ratio n-6/n-3 in lamb meat, thus suggesting that pasture rearing can be recommended for improvement of meat dietetic quality.