The Canadian Dairy Cow Diet

Article 3 min

The food we eat contributes to our overall health and a well-balanced diet will give you more of what you need. The same goes for dairy cows. So, what’s a nutritious meal for a dairy cow? Scientists have long studied the topic to help set dietary standards and to ensure our cows stay as healthy as possible. Let’s take a look at what Canadian cows have on their menu.

By DFC - PLC, Communications Team
Dairy cows in a pasture in Canada
Cows in a pasture


  • The most common food for cows is grass
  • A typical mature cow will eat approximately 29 kg of feed every day
  • Canadian dairy farmers work closely with cow nutrition experts to find diets that work best for their specific cows

It’s been said that you are what you eat (there’s a small chance you pictured yourself as a sentient bowl of mac and cheese for a second—and if you didn’t before, you did now). The point is that we recognize the importance of consuming quality food. In order to provide us with pure, nutritious milk, our cows are fed a research-backed diet that works best to meet their nutritional needs at each stage of life. Healthy cows produce more (and better quality) milk!

What do cows eat

Our dairy cows’ diets may vary according to the crops a farmer plants, which in turn depend on climate, soil type, and other considerations. In Canada, the most common food for cows is grasses (grass, alfalfa, corn stalk and leaves), which are served up in two different ways: dry hay and silage. Canadian dairy cows might also get important nutrients from crops such as corn, barley, clover, alfalfa hay, oats, and soybeans. Cows, because they are ruminants, also have the cool capacity to get nutrition from stuff that would otherwise be food waste, like soybeans that do not make the ‘human grade’ cut, or ‘grain meals’ such as crushed barley left-over from making beer!

Did you know that cows eat the entire plant? Not just the grains or flowers, but the leaves and stalks too. 

Tractor with a full load of hay silage in a summer farm field
Tractor with a full load of hay silage in a summer farm field.

To top that off, our dairy farmers work closely with a cow nutrition expert. To ensure that our ‘dairy queens’ are receiving proper nutrition, cow feed is routinely tested. Their diets are determined based on their requirements for energy, fibre, carbohydrates, proteins and fat.  The cow nutrition experts  test the nutritious value of the crops grown on the farm at the time the farmer opens up that silo. The nutrition expert then uses that analysis to help formulate diets that work best for specific groups of cows. For example, dietary needs will vary depending on the time of the year and their stage of lactation. This includes choosing the right vitamin, mineral or other types of supplements to ensure all cows enjoy a well-balanced diet that supports their needs.  

Additionally, our farmers manage feed distribution, so all cows get the nutrition they need, and cows with specific needs receive special attention. All of this helps keep our cows well-fed and healthy.

In one day, a typical mature cow will eat approximately 29 kg of feed and wash that down with 80 to 180 L of water. She’ll spend several hours relaxing and ruminating – in other words chewing the food that’s returned to her mouth from her stomach for a second chewing. To each their own!

Grass vs. other plants

Most Canadian dairy farmers feed their cows a combination of grass and other plants, including grains, as mentioned above. However, there’s been growing consumer interest in grass-fed dairy for a variety of reasons, including its slightly higher omega-3 content. But what is grass-fed dairy?

It’s a bit of a misnomer, since it’s the cows that are predominantly grass-fed, not the dairy products!

In Ontario, a temporary standard was implemented to define what it means for a cow to be considered “grass-fed”. To meet the standard, 75% of its feed must consist of any herbaceous plants that can be grazed or harvested, including grass, legumes, brassicas, tender shoots of shrubs and trees, and cereal grain crops in the vegetative state. Since then, other provinces have considered putting in place a grass-fed standard. Dairy Farmers of Canada has helped develop guidelines for a unified national standard.

On organic dairy farms, cows must only eat organically grown crops.

Whether they produce conventional, grass-fed or organic milk, animal health and wellness come first on any Canadian dairy farm. Nutritional balance is a must, as are proper farm management practices. At Dairy Farmers of Canada, we believe in looking at dairy farming holistically, and we continue to invest in scientific research that helps us continue to better understand the dietary needs of cows.   Together, Canadian dairy farmers, cow nutrition experts, and vets are keeping a close eye on our dairy superstars, so we can enjoy the natural goodness of Canadian milk.

The Wert family
Stanlee Farms is four generations in the making and the Wert family have been a part of the Avonmore, Ontario community since 1864.


Farm & Food Care Ontario. “Facts & Figures About Canadian Dairy Cows.”

National Farm Animal Care Council. “Code of Practice for the care and handling of farm animals - Dairy Cattle.”

BC Dairy Association. “What do dairy cows eat?”

Dairy Farmers of Ontario. “Interim Grass fed milk Standard Protocol.”

Organic Council of Ontario. “Organic: More than just grassfed.”

Haspel, Tamar. “Is grass-fed beef really better for you, the animal and the planet?”