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Cow pee is an environmental problem. But now scientists say calves can be potty-trained.

September 15, 2021 at 4:21 a.m. EDT
Scientists in New Zealand and Germany have developed a system of potty-training calves: the "MooLoo." Cow urination produces methane, a harmful greenhouse gas. (Video: Research Institute for Farm Animal Biology)

A herd of “clever cattle” in Germany have successfully been potty-trained and can now relieve themselves in a designated area nicknamed the “MooLoo,” scientists say — a move that they hope will help lower greenhouse gas emissions amid the global warming crisis.

There are an estimated 1.4 billion cows on Earth and they happen to emit a lot of harmful waste products — through burping, urination and defecating — making the animals a major driver of climate change.

Their frequent urination produces 55 to 110 gallons of methane each day and contains nitrogenous components that pollute Earth’s streams and rivers, make the waters dangerous for people to swim in or drink from, and pose a risk to wildlife.

The University of Auckland joined forces with scientists at a research laboratory in Germany for an experiment that would allow the cow’s urine to be collected, treated and neutralized — so it poses less of a risk.

According to researchers, 11 out of 16 calves were taught to use the MooLoo in just 15 training sessions — a result they said compares favorably to the amount of time it takes to toilet-train children ages 3 to 4.

“The common perception is that cows are placid, lovable, but perhaps not as bright as other animals,” said Lindsay Matthews, a New Zealand-based animal behavioral expert and one of the lead authors of the study. “The cute thing here is that the animals are causing a problem, because of [intensive] farming practices. And here, we can have them as part of the solution, by using their underestimated intellect.”

During the training process, the animals were rewarded with a sweet treat when they urinated exactly where they were supposed to go — in a special pen installed in their barn. If they toileted outside of the area they were offered a mild punishment: a short burst of water.

As the experiment continued, the animals continued to enter the “MooLoo,” building a habit, the researchers said, a sight they celebrated given that past efforts to toilet-train cattle had not been entirely successful.

“Within one or two urinations, most of the animals were walking down the alleyway, pushing open the door and going into the toilet,” said Matthews. The researcher, who grew up on a dairy farm, said that it would be “nice if cows can be seen in a bit better light through this sort of research” — given the bad rap they’ve had lately due to the long list of problems that farming poses for the planet.

The authors of the report said that the calves “showed a level of performance comparable to that of children and superior to that of very young children.”

However, experts point out it will take more than trained calves and “MooLoos” to save the planet.

Andrew Knight, a veterinary professor of animal welfare at England’s University of Winchester, told The Washington Post in an email that while the idea “sounds nice in theory,” it would “do little to prevent the major contributions to climate change” because the world’s reliance on intensive livestock production — including milk and dairy — is far too great.

Knight, who was not involved with the MooLoo experiment, added that “nitrous oxide is a very potent greenhouse gas, with 296 times as much global warming potential as CO2,” and livestock produces “more greenhouse gases, than all the cars, trucks, planes in the world, combined.”

Knight also pointed out that the technology and skills needed to neutralize damaging components in cow waste come at a financial cost too great for many of the world’s farmers.

“Much more drastic steps are required, if we are to have any realistic chance of avoiding global climate breakdown in the medium-term future,” he warned.

For places like the Netherlands, however, which is considering plans to force hundreds of farmers to cut livestock numbers to reduce damaging ammonia pollution, the financial upside of training cows to pee in a toilet is that they could sustain bigger herds, Matthews said.

The country has been grappling with what officials are calling a “nitrogen crisis” — where livestock manure, when mixed with urine, releases ammonia, a nitrogen compound that can get into lakes and streams via farm runoff, damaging natural habitats and causing algal blooms. Officials have proposed reducing livestock numbers by 30 percent, one of the most radical plans of its kind.

“If you had to lose 30 percent of your animals or you had to collect 50 percent of your urine, that’s a potential trade-off that could be made that you can retain more animals if you can collect the urine,” Matthews said.

One final caveat — the experiment did not involve training cows to poop in a specific location, but this is something that may be tested in future.

Matthews said the idea now is to expand the research into how to make the toilet-training techniques scalable — something he thinks could be more easily achieved in places like the United States where cattle are often reared in feedlots, meaning the animals wouldn’t need to go as far to use the bathroom compared with pastoral farming.

He is also discussing a different toilet-training approach with New Zealand’s powerful dairy industry, where cows can spend much of their day grazing in fields. The country’s lush countryside has helped transform the nation into one of the world’s top dairy exporters — but, as in the Netherlands, the farming has led to the environmental pollution of waterways. One possible solution? To train the animals to hold on between twice-daily milking sessions, so they can use “MooLoos” located alongside the barn.

Researchers say that even if they could collect 10 or 20 percent of global cow urinations, it would be sufficient to reduce greenhouse gas emissions and nitrate leaching significantly. Nitrous oxide, a long-lived greenhouse gas 300 times as potent as carbon dioxide, accounts for 12 percent of New Zealand’s greenhouse gas emissions — and much of it comes from the agricultural sector.

“It could be a way to reach [environmental] targets without having to reduce animals in the process,” Matthews said.

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