Passing by fields of cows, you’ll notice some resting, but most will be grazing. Many of us think of cows chewing their fresh grass or cud when imagining their diet, but there’s more to a cow’s diet than what they find while mowing a field. 

Dairy farmers follow sustainable farming practices for the environment and for the health of their cows. They look for how to reduce waste while benefitting their cows. One way dairy farmers adapt their traditional farming practices into sustainable farming practices is through what their cows eat. 

Actually, what cows eat is a big part of dairy farming. Remember, dairy cows weigh at or above 1,000lbs depending on their breed, so cows can eat a lot—up to 100lbs a day. To provide cows their nutritional requirements, dairy farmers feed cows living in barns a mix of feed they call Total Mixed Ration, or TMR. Below is what a dairy cow’s TMR may include. 

Most of a dairy cow’s diet is comprised of plants. This part of the diet consists largely of corn and its leaves and/or chopped alfalfa and its hay.  

In addition to plants, cows also enjoy grain. While cows can receive grain grown specifically for their meals, cows also consume Distillers grain and Brewers grain. Distillers grain is a byproduct of ethanol production. Brewers grain, meanwhile, is a byproduct of brewing beer from rye, oats, wheat or barley. 

The surprising part of a cow’s diet is the part of food that humans would throw away. Leftover soybeans and canola used in producing cooking oil, almond hulls, cotton byproducts like leftover cottonseed and even citrus pulp from juice. Cows can consume what would otherwise become waste and put those nutrients to good use. How? 

These products, which were once thrown away, are good for cows. With their four-chambered stomachs, cows can breakdown products humans cannot and use the energy and nutrients in these products that would otherwise go to waste. Wow!