Herbs for cows: less methane and better milk

The BioDiverseMelk project, led by Marije Strikwold from Van Hall Larenstein University of Applied Sciences alongside researchers from Wageningen University & Research and Van Hall Larenstein, examines the effects of herb-rich grasslands on both emissions and milk composition. Researchers focus on determining which herbs in which quantities lead to emission reductions and what consequences these have for milk.

Research at Dairy Campus shows that feeding cows specific fresh grassland herbs — such as chicory and narrow-leaf plantain — can lead to methane emission reductions of up to about 30 percent. In addition, these herbs have a positive effect on the fatty acid composition of milk, with higher levels of polyunsaturated fatty acids — generally considered healthier than saturated fats — in the milk of cows fed these herbs.

The chicory’s rapid digestibility and bioactive components such as tannins may contribute to its methane-reducing effect. Narrow-leaf plantain also showed reductions, though to a lesser extent. Research into red clover and its impact on nitrogen emissions is ongoing. While cows in the trial were given 100% freshly cut herbs or grass supplemented with concentrate feed, farmers are unlikely to feed cows diets consisting entirely of herbs in practice.

Future research will measure emissions with practically applicable amounts of herbs in pastures and investigate the effects of herb combinations. The project offers a hopeful perspective for a more climate-friendly future in the dairy sector, providing scientifically grounded tools for dairy farmers to produce dairy products that contribute to agriculture’s sustainability.