Enhancing the sustainability of pasture-based sheep systems by reducing methane emissions and increasing production is a global priority. In the current study, lambs grazed one of 5 differing sward types, namely, a perennial ryegrass monoculture or one of 4 binary sward mixtures, perennial ryegrass and white clover, perennial ryegrass and red clover, perennial ryegrass and chicory or perennial ryegrass and plantain. The fiber contents in the sward were reduced with the inclusion of any companion forage, while the addition of white clover or red clover also increased the crude protein and digestibility of the sward. Lamb weight gain was enhanced with white clover, red clover, or chicory inclusion while lamb age at slaughter was reduced by 16 to 50 d for those grazing any binary sward mixture. The inclusion of white clover, red clover, or plantain reduced methane emissions by 6% to 13%, while also reducing methane intensity. This research supports the use of binary sward mixtures in intensive pasture-based sheep production systems as a practical and effective strategy to improve production efficiency and mitigate methane emissions in lamb finishing systems.

Read the full article in the Journal of Animal Science.