Do herbal leys affect milk yield and quality?

Establishing diverse swards can improve the resilience of grazing platforms. However, the un-quantified effect of increased sward diversity on milk yield and quality is a potential financial risk for dairy farmers. This effect on milk has not been trialled and recorded in the UK before.

In this Farm Net Zero field lab two farmers will monitor the difference between milk produced by cows grazing a rye grass sward, and cows grazing a herbal ley / diverse sward.

Alongside the trial a discussion group of Cornish farmers will explore the benefits of their own herbal leys, and follow the trial results.

The idea for this field lab arose from the Farm Net Zero project discussion groups, and it is part of the Farm Net Zero Project in Cornwall, funded by the National Lottery Community Fund.

The research is being led by Dr Daniel Enriquez Hidalgo of Bristol Veterinary School, with assistance form Cornwall Wildlife Trust and Trifolium Services.

There are many accepted benefits of growing herbal leys, they can:

Improve soil structure and health
Provide resilience in dry periods
Extend the grazing season
Benefit carbon sequestration
Nitrogen fixation from legume species – so requires little fertiliser
Improve livestock growth rates when rotationally grazed
Improve biodiversity of bird and insect species
Some species have anthelmintic properties – so less need for wormers

However, there has never been a study in the UK looking directly at the impacts of herbal leys on milk for dairy farmers.

In this field lab Andrew Brewer, a Famr Net Zero Monitor farmer, will split his herd into two groups. One group will graze a rye grass sward, and the other a herbal ley / diverse sward. Andrew will then monitor the milk yield and constituents fortnightly throughout the grazing season, and Cornwall Wildlife Trust will be sampling the forage monthly, to get an idea of which species are dominating.

For more information and updates on the trial see the Innovative Farmers website.