We Eat Cows, But What Do Cows Eat?

Cows need to maintain a healthy and complex diet


Hay is cows' primary source of fiber. 

If you should happen to find yourself with 100 or so cows on your hands, one of your first thoughts will be probably be what to feed them. In order to stay in good shape, they need to eat a healthy and well-balanced diet.

According to the British Columbia Dairy Association, the average cow needs to eat about 100 pounds of food every day to stay in tip-top shape. Cows are usually fed dried grass and alfalfa (hay), corn, barley, oats, and oilseeds like soybeans. Silage, or fresh grass and grains that have been fermented for preservation and extra nutritional content, also make up a substantial part of their diets, and extra vitamins and minerals are also incorporated into the mixture. Cows will also be fed “co-products,” or leftovers from human food production; this can include distiller’s grains, bakery waste, apple pomace, and corn cannery waste. All of these ingredients (called feedstuffs) are combined into something called TMR, or total mixed ration, before being fed to the cows.


The exact ratio of feedstuffs is vitally important to the health of livestock. Roughage like hay and silage is high in fiber so it helps keep the digestive tract moving, but it’s low in energy. Grains like corn and barley are low in fiber but high in energy, and older cattle are fed more grain before they go to market (this is why most grass-fed beef is “grain-finished”). Oilseeds provide calories, protein, and fiber. And co-products need to be tightly regulated because each one is different; corn waste, for example, is very high in sugar.