Methane Emission and Milk Production from Jersey Cows Grazing Perennial Ryegrass–White Clover and Multispecies Forage Mixtures

Methane is a major constituent of greenhouse gas (GHG) emissions from ruminants, and mitigation strategies are needed to alleviate this negative environmental impact while maintaining the other benefits grazing systems. Forages containing plant-specialized metabolites (PSM), particularly condensed tannins, may help reduce enteric methane (CH4) emissions. However, information on in vivo CH4 cows mixtures that contain bioactive herbs scarce. Accordingly, study compared binary mixture perennial ryegrass (Lolium perenne) white clover (Trifolium repens) against diverse six additional species, including tannin-rich species like birdsfoot trefoil (Lotus corniculatus) salad burnet (Sanguisorba minor), full-grazing dairy system. Enteric were measured using SF6 tracer technique. Cows increased their energy-corrected milk (ECM) yield by 4% (p < 0.001) with mixtures. per kg ECM also 11% greater for 0.05). The very high feed quality both explained low recorded relative output. addition forbs did not provide at these intensities, as they maintained shares throughout.