Potty-Trained Cows and Bovine Bathrooms Can Mitigate Climate Change

When you potty train your children, you save them the embarrassment of having soiled clothes. When you potty train your pets, you save your carpets. When you potty train cows, however—yes, cows—you can help save the environment.

So suggests a new study by scientists at New Zealand’s University of Auckland and, in Germany, the Research Institute for Farm Animal Biology (FBN), the Friedrich Loeffler Institute (FLI), and the University of Rostock. Published in the journal Current Biology, the study found cows can be trained to urinate in livestock latrines, where their waste can be easily collected and treated so as to reduce its environmental impact.

Typically, researchers point out, cows are allowed to relieve themselves in the fields where they graze, which can contaminate local soil and waterways. An alternative is confining cows to barns. But that’s not much better for the planet, as bovine waste in confined spaces creates ammonia gas, of which agriculture is the world’s largest emitter. Although it doesn’t contribute directly to climate change, ammonia gas may leach into the ground, where soil microbes convert it into nitrous oxide—the third-most consequential greenhouse gas next to methane and carbon dioxide.

Given ammonia’s environmental impact, researchers set out to discover whether cows could be taught to control their bladders. They, therefore, devised a potty-training method they called “MooLoo” training, which was tested on a group of 16 calves.

“It’s usually assumed that cattle are not capable of controlling defecation or urination,” Jan Langbein, an animal psychologist at FBN and one of the study’s co-authors, said in a statement. “Cattle, like many other animals or farm animals, are quite clever and they can learn a lot. Why shouldn’t they be able to learn how to use a toilet?”

First, they rewarded the calves with a sweet, molasses-based liquid when they urinated in the MooLoo—a pen carpeted in AstroTurf, under which are grates through which urine flows for collection. When calves urinated outside the MooLoo, they received as a deterrent a mild punishment: a splash of water.

“As a punishment we first used in-ear headphones and we played a very nasty sound whenever they urinated outside,” said Langbein. “We thought this would punish the animals—not too aversively—but they didn’t care. Ultimately, a splash of water worked well as a gentle deterrent.”

As it turns out, they can: Within just a couple weeks—15 days, to be exact—researchers had successfully trained 11 of the 16 calves to use the MooLoo.

Next, researchers plan to translate their training methods into real cattle housing, as well as outdoor systems. “In a few years, all cows will go to a toilet,” prophesied Langbein, who said researchers will continue to refine their training methods to suit a variety of cattle. “After 10, 15, 20 years of researching with cattle, we know that animals have a personality, and they handle different things in a different way. They are not all the same.”

Although the experiment focused only on urination, Lindsay Matthews, an animal behavioral scientist at the University of Auckland and the study’s lead author, says cows likely can be trained to defecate in designated places, too—but not to stifle their methane-rich belches, which have previously been cited as a contributor to climate change. The cows would blow up, according to Matthews.

Still, training cows to urinate in MooLoos is a major win, the researchers contend. “By reducing contamination of the living areas, the cleanliness, hygiene, and welfare of livestock can be improved whilst simultaneously reducing environmental pollution,” they state in their study. “Hence, clever cattle can help in resolving the climate killer conundrum.”