How ardently do cows desire going out to pasture? Quite a lot, it seems. A new study shows that the animals are as motivated to get their feet into clover as they are to eat.
As detailed in a paper in the journal Scientific Reports, researchers came up with a scheme to measure how driven cows were to either access food, or go out to pasture. The team, led by Marina von Keyserlingk and Daniel Weary at the University of British Columbia, steadily increased the amount of force it took for a cow to open a door, which led to either food or pasture.
The scientists found that the majority of the 22 cows they studied pushed equally hard to get to food or to access the outdoor areas. They noted that the cows at the British Columbia research farm, were much more interested in going outside at night, compared to the day. Once outside, many of them laid on the ground to sleep. (Von Keyserlingk says it may be uncomfortably hot during the day—the study was conducted in the summer—and that the cows prefer to stay inside where it is cooler in the daytime.)
The majority of dairy cows in the United States don't spent time in pasture, which new research suggests they highly desire access to. Russell Cheyne/REUTERS
That’s significant, since fewer than 5 percent of cows in the United States spend a majority of their time in pasture, and “80 percent never see a blade of grass,” von Keyserlingk says.
Surveys of dairy farmers suggest that many would like to let their cows out to pasture, but worry that it would reduce the amount of milk they produce, Weary says. However, work done by the group shows that animals who spend the night outside produce the same amount of milk. Thus, letting Holsteins out in the evening is any easy way to improve the well-being of cows without sacrificing milk production, Weary says.
James Drackley, a professor of animal sciences at the University of Illinois who wasn’t involved in the research, says it's a “well-controlled and well-interpreted study” but notes that it doesn’t tell us anything about the welfare of cows who don’t get to go outside. There are many valid reasons for keeping cows indoors, he says—for example they prefer cooler conditions than humans, and being outside exposes them to inclement weather and predators.
It’s unclear exactly why cows desire to be outside, but it isn’t surprising, since grasslands are their natural environment (duh). One specific reason they seem to enjoy it is that it’s softer than indoor pens, which are often made of concrete, and thus more comfortable for walking and laying down, von Keyserlingk says. Pasture also allows them to move more freely and exercise, and the soft ground is better for hoof health and reduces the likelihood of lameness. Past research conducted by the team shows that cows let outside don’t eat less than those on the inside, suggesting that eating grass isn’t a prime motivator, at least for these Canadian cows.
Animal welfare groups generally advocate for allowing cows outdoor access (at a minimum; some oppose dairy farming altogether). The Humane Society released a 2009 report arguing that many cows aren’t raised in ideal conditions. “Providing regular access to pasture and suitable high-fiber diets could help alleviate the health, stress, and behavioral problems associated with confinement,” the group concluded.