17 March 2024

Pasture, present and future

Is pasture-based Irish milk truly better than milk from conventional indoor feeding? To examine this question, researchers from Teagasc and Food for Health Ireland conducted one of the largest, most in-depth trials of its kind.

There is a growing demand for dairy products produced from pasture-fed animals, as consumers perceive pasture feeding as a more natural and holistic form of milk production. Pasture-fed differs from grass-fed in that it not only ensures that cows are fed large proportions of grass in their diet, but also warrants that the animals consume this feed while outdoors at pasture and can therefore follow their natural grazing behaviour.

Despite this demand for pasture-fed produce, the majority of dairy products sold around the world do not originate from pasture-fed animals, with farmers worldwide preferring to operate an indoor mixed ration feeding system. This preference often results from the greater difficulty of growing high-quality grass pastures in many regions of the world. However, the feeding of a mixed ration to housed animals also allows a greater control of animal nutrition, resulting in a larger milk production than that of pasture-fed animals.

In contrast to this, due to Ireland’s ability to grow large quantities of high quality pasture for animal consumption, Irish dairy farms provide higher quantities of grazed pasture in the cow’s diet than the majority of countries around the world. Similarly, because of the temperate climate in Ireland, Irish cows enjoy more time at pasture and a much higher number of days at pasture compared to anywhere else in Europe and the majority of the world.

Fat chance

Recent research conducted at Teagasc Moorepark segregated cows into three herds of 18 cows who consumed three different diets for comparison: a high pasture allowance diet, typical of that operated by Irish farmers; a medium pasture allowance diet; and no pasture allowance diets, typically operated in most regions around the world.

Milk was collected from the three herds weekly across nine months and tested for its composition, properties and nutritional parameters, such as the fatty acid profile, in order to distinguish Irish dairy from that produced worldwide.

Mark Timlin, a postdoctoral researcher at Teagasc Moorepark, explains: “Despite the higher milk yields achieved by the no pasture allowance diet, the high pasture allowance diet, typical of Irish dairy, produced milk with better fatty acids for human consumption. These fatty acids can be absorbed into the human gut and provide vital nutrients for us humans.”

The high pasture allowance diet produced milk with the healthiest fatty acids for human consumption, with the fatty acids most notably altered including:

141% increase in conjugated linoleic acids (CLA)
83% increase in omega-3 fatty acids
14% increase in unsaturated fatty acids.

These fatty acids are associated with significant health benefits including improved eye, brain and cardiovascular health in addition to an improved immune response.

Further analysis of the milks also demonstrated an improved udder health of the animals maintained on the high pasture allowance system, as indicated by the lowest somatic cell count in the milks they produced, Mark explains.

“Additionally, the milks increased in yellow colour with an increase in the animals pasture allowance, originating from the relatively large proportions of colour pigments — called carotenoids — in the leafy grass pastures. Not only do these carotenoids naturally provide Irish high pasture allowance milk and dairy products with a characteristic yellow colour, but the carotenoids are also broken down into vitamin A in the body, an important nutrient for normal vision and immune system.”

Setting the standard

The high pasture allowance system in this study is reflective of the Bord Bia standard for Irish dairy. Dairy products sold with this standard displayed on their packaging around the world reassure consumers that the product within is derived from Irish cows that consume a minimum of 90% grass or grass forage and are maintained at pasture for an average of 240 days a year.

To guarantee these products meet the requirements set by the Bord Bia standard, farmers providing milk for these dairy products are assessed regularly through Bord Bia’s Sustainable Dairy Assurance Scheme, ensuring these dairy products meet both sustainability and quality assurance criteria.

As Mark says: “Consumers will now have the comfort in knowing they are buying a premium dairy product, which not only provides essential nutrients, but also ensures the farms from which it came from are providing their animals with a more natural way of life.”

The researchers of the Food for Health Ireland project in Teagasc and University College Dublin have undertaken further research into increasing animal pasture allowance and its impact on the production, functional properties, textural attributes and their impact on human health of butter, cheese and whole milk powders. This research is reaching its conclusion, and its results will add invaluable understanding to the benefits of the consumption and desirability of Irish dairy products, which are currently retailing in over 130 countries around the world.