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Milk from grass-fed cows can become a new, healthy and holistic organic luxury product

Organic dairy farming can become even greener if the milk is produced almost exclusively on grass-based feed. This type of production will the make both the milk and the organic production system healthier.

2017.11.28 | Janne Hansen

When grass comprises a large proportion of a cow's feed it alters her milk composition. Photo: Colourbox

Milk produced exclusively on the basis of grass can become an interesting new organic product. Not only does grass-based milk have a high proportion of beneficial fatty acids, the production method can also contribute to a more balanced organic production.

A new project under the management of researchers from the Department of Agroecology at Aarhus University will develop and document milk production based on a very high proportion of grass-based feed partly as a differentiated product, and partly as an organic production system that can contribute nutrients and feed to the other sectors of organic farming.

- Milk from grass-fed cows is not a new phenomenon but has not been studied very much under Danish conditions and as part of a coherent organic system. There is therefore a need to investigate how grass can be incorporated in dairy cattle feeding in much greater quantities than is presently the case, says the leader of the project Senior Researcher Troels Kristensen from the Department of Agroecology at Aarhus University.

Well-balanced organic food production

In order to achieve a well-balanced organic production, organic dairy production must contribute nutrients to arable crop production and feed to the pig and poultry sectors. The grass-clover field is central. A grass-clover field acts as a motor in the organic nutrient cycle in that clover takes up nitrogen from the air. This nitrogen can then be used by the cereal crops that follows. A well-balanced organic production is one that has the right proportions of grass-clover and cereals.   

Grass, both fresh and preserved, is also good for cows. Grass can supply the organic dairy cow with just about all the energy and nutrients it needs. Milk from cows that are fed almost exclusively grass has a higher content of omega-3 fatty acids than regular milk.  

There are two prerequisites for success and profitability in such a production. One is to optimise the cattle’s utilisation of the grass feed. The other is to use the animals’ manure and the grass-clover fields’ nutrients to produce cereals and other edible crops. It is therefore necessary to focus on the dairy cows’ intake and utilisation of grass feed.

Model calculations and studies on commercial farms

The researchers will collaborate with two dairy cattle farms where the animals will be fed a large proportion of grass-based feed in different ways, including grazing, feeding with fresh grass, and feeding with silage.

In addition, the researchers will carry out more intensive feeding trials at AU Foulum in collaboration with the Danish Cattle Research Centre in order to document the effects on milk composition and other traits, as well as livestock productivity and feed energy utilisation.

Using model studies, the researchers will analyse the overall perspective in relation to the production system’s potential in relation to an increased and more well-balanced production of organic foods, and they will calculate the consequences for a range of scenarios with various proportions of dairy, egg, pork and crop production. They will make calculations regarding the sustainability of the different scenarios, i.e. their economics, nutrient utilisation, and greenhouse gas emissions.  

Facts about the project:

Title: Græsmælk (Grass Milk)

Granted: 600,000 Danish kroner from Fonden for økologisk jordbrug (Organic Farming Fund) and 893,000 Danish kroner from Mælkeafgiftsfonden (Milk Levy Fund) in 2018

Collaborative partners: Seges, Thise Mejeri, Arla, and the Department of Agroecology, Department of Animal Science, and Department of Food Science, Aarhus University

Duration: Three years (2018-2020)

Visit the Græsmælk website (in Danish)

For more information please contact:

Senior Researcher Troels Kristensen, Department of Agroecology, email: troels.kristensen@agro.au.dk, telephone: +45 8715 8014, mobile: +45 2612 5583



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