Quirks & Quarks

Potty-trained cows can help solve pee pollution problem, study finds

Nitrogen in cow urine can pollute surface and groundwater and create a potent greenhouse gas, so teaching them to use a "toilet" could be an environmental win.

Nitrogen-rich cow urine contaminates air and contributes to greenhouse gases

A calf enters a pen specially designed for cattle to urinate in, as part of a study to find out whether cows can be toilet-trained. (Research Institute for Farm Animal Biology)

If you've never imagined a cow getting potty trained — and who could blame you if you haven't — now is a good time to start. A new study, published this month in Current Biology, provides details of how to do it, and one big surprise is that the speed at which cattle can be toilet-trained rivals human toddlers.

"We know that toddlers can take weeks or months to learn, but the fastest can learn in a few days, so the fastest of our cows were as fast as the fast toddlers," said Lindsay Matthews, an animal behavioural scientist at the University of Auckland, in New Zealand.

Cow urine can be damaging to the environment in a number of ways. When cattle relieve themselves outdoors, their nitrogen-rich urine breaks down in the soil into nitrate and nitrous oxide.

Both of those substances come with their own problems. Nitrate leaches into and pollutes local lakes, rivers and aquifers. Nitrous oxide is a powerful greenhouse gas 300 times more potent than carbon dioxide, according to the United States Environmental Protection Agency (EPA).

Ammonia in cow urine can be detrimental to human and cow health indoors. When outdoors, the ammonia leaches into the soil, microbes convert it into nitrous oxide, which is the third-most significant greenhouse gas after methane and carbon dioxide. (Darryl Dyck / THE CANADIAN PRESS)

For cows that spend most of their time indoors, their urine mixes with feces to create toxic ammonia, which is problematic for cow and human health, and also an indirect contributor to climate change. 

Matthews told Quirks & Quarks host Bob McDonald that even getting rid of some of this pollution could have "massive implications" for the environment.

Secret to their success

Toilet training techniques for cattle turn out to be very similar to how we train human toddlers. The researchers had 16 calves as their training subjects.

They first verified that cattle had the capacity to control their urinary reflex — or "hold it in." They conditioned them with a collar that vibrated if they started peeing in the wrong place.

Once they did that, then it was time to introduce their new "toilet."

They dressed up an enclosure with green walls, a soft green textured floor and a green sign on the gate. The unique markings helped signal to the cows that this is where they're supposed to urinate.

"The key thing is to have the place of the toilet really firmly locked in their behaviour," said Matthews.

Observers watch calves undergo toilet training. (Research Institute for Farm Animal Biology)

They brought the calves into the enclosure to get them comfortable with it, similar to having a toddler get used to sitting on a toilet.

The next step was to give them a tasty treat of grain or water sweetened with molasses when they were finished to teach the cows that urinating in this location was a good idea.

"It was so exciting because we got the results rather quickly in the sense that the cows showed us within a few urinations that they had clicked — that urine leads to reward — because it would spin around halfway through urination and wait for the reward dispenser to lick up the nice, tasty treat." 

The next step was to release the calves into an area where their new toilet was nearby, to see if they would use it on their own without any prompting. Again, they were surprised and gratified by how quickly the cows caught on.

Within 15 to 20 urinations, on average, the calves would go into the enclosure to pee all on their own.

Scientists from New Zealand and Germany created this cow 'potty' enclosure to train calves how to urinate in a certain location. (Research Institute for Farm Animal Biology)

"Sometimes they had a wee accident and we'd give them a squirt of cold water, and that would then usually inhibit the urination," said Matthews. "Then they would usually trundle down to the toilet, push open the door and go in and restart." 

He said he was impressed with how quickly they learned, and the fact they were able to do this at all. 

"To actually get to the stage where you have to pay attention to your bladder filling, recognize that and then do something about it, inhibit the desire to urinate, walk somewhere else, go through a gate and reinitiate urination? That's a complex process," he said.

Scaling up the training process 

Given there are about a billion head of cattle in the world, Matthews said technology could easily be developed to help implement and automate this training technique for large farming operations.

Training cows indoors where you can arrange toilets or find ways to get them there, he said, would be less of a challenge than training cows that spend a lot of their time outdoors.

Technology that can assess the cow's posture to look for signs it has to pee, or that can determine if liquids are coming out, could be linked to a reward delivery system.

"We just see that as a technical problem," said Matthews. "That's not psychologically challenging for the animal or anything, it's just doing what we did manually."

Produced and written by Sonya Buyting. To hear the interview with Lindsay Matthews, click on the link at the top.

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