Media release

From: University of Auckland

Research to toilet train cows aims for positive environmental  impact 

University of Auckland-affiliated researchers have successfully demonstrated  that cows can be toilet trained. It’s no joke. Lindsay Matthews and Douglas  Elliffe’s research with German colleagues could help reduce water contamination  and greenhouse gas emissions.

Cow urine is high in nitrogen. As it breaks down in the soil, it results in two  problematic substances – nitrate and nitrous oxide. Nitrate from urine patches  leaches into lakes, rivers and aquifers, where it pollutes water and contributes to  the excessive growth of weeds and algae. Nitrous oxide, a long-lived greenhouse  gas 300 times more potent than carbon dioxide, accounts for 12 percent of New  Zealand’s greenhouse gas emissions – and much of it comes from the  agricultural sector.

If cows could be trained to urinate in a “toilet” at least some of the time,  nitrogen could be captured and dealt with before it pollutes water or turns into  nitrous oxide gas. Matthews and Elliffe’s research detailing how has recently  been published in the prestigious journal Current Biology* and will be profiled in  an upcoming issue of Science.

“We’ve shown proof of concept that we can train cows and train them easily,”  said Elliffe, a University of Auckland professor of psychology. “Cattle urine is a  major cause of our nitrogen problem. Any reduction in that would make a  difference.”

“People’s reaction is, ‘crazy scientists,’ but actually, the building blocks are  there,” said Matthews, a University of Auckland honorary academic and director  of an independent research company. “Cows have bigger urinations when they  wake up in the morning, which demonstrates they have the ability to withhold  urination. There’s nothing in their neurophysiology that radically differentiates  them from animals, such as horses, monkeys and cats, that show latrine  behaviour.”

Matthews has been around cows for a long time – he grew up on a dairy farm  and did his PhD research on learning and preference in cows. In 2007, during a  radio interview about the environmental impact of cattle excretion, the host  suggested Matthews should toilet train them. It was a joke – but it got Matthews  thinking.

In 2015, Matthews was working with Professor Lars Schrader at the Federal  Research Institute for Animal Health in Germany when Schrader suggested toilet  training to deal with ammonia emissions, which result from contact between  faeces and urine. Previous international attempts to toilet train cows had seen  little success, but Matthews thought that with his deep expertise, he might be  able to do better. He brought in Elliffe, who has complementary skills in  behavioural analysis, to help.

With their German colleagues, Matthews and Elliffe worked with 16 calves at a  farm operated by the Research Institute for Farm Animal Biology in Germany.  First, they demonstrated that most calves could be trained to “hold it.” If they

began to urinate in the wrong place, the scientists would make their collars  vibrate. While the vibration didn’t hurt them, most of the calves soon learned to  walk a short distance to a latrine pen.

Next, Matthews and Elliffe put the calves in the latrine pen, which was bright  green to differentiate it from other pens, and rewarded them with a favoured  food treat if they urinated there.

“This is how some people train their children – they put them on the toilet, wait  for them to pee, then reward them if they do it,” said Matthews. “Turns out it  works with calves too. In very short order, five or ten urinations for some  animals, they demonstrated they understood the connection between the  desired behaviour and the reward by going to the feeder as soon as they started  urinating.”

The next progression was to increase the distance cows had to walk to the  latrine. If “accidents” occurred in another part of the barn, scientists would  squirt a little cold water at them. Most of the calves soon learned the ultimate  toilet-training skill.

“Very quickly, within 15 to 20 urinations on average, the cows would self-initiate  entry to the toilet. This is very exciting because it means they were paying  attention to their bladder getting fuller,” said Matthews. “By the end, three quarters of the animals were doing three-quarters of their urinations in the  toilet.”

The calves received only 15 days of training and the majority learned the full set  of skills within 20 to 25 urinations, which compares favourably to toilet-training  time for three- and four-year-old children.

The next step for Matthews and Elliffe is to bring their research to the New  Zealand context. In the Northern Hemisphere, cows spend much of their time in  barns. In New Zealand, they spend most of their time outdoors. This makes  toilet training more of a challenge. However, cows do gather for milking and  receiving supplements, so it may be possible for them to use a latrine at those  times. Installing latrines outdoors may be another possibility. Even if these  changes result in a lower success rate, reducing urine patches would have  significant environmental benefits.

“If we could collect 10 or 20 percent of urinations, it would be sufficient to  reduce greenhouse gas emissions and nitrate leaching significantly,” said Elliffe.

Another challenge will be to scale up so it’s economically feasible to train millions  of animals. This could be accomplished by using urination-detecting sensors and  automatic reward systems. Trained cows could be transitioned into not expecting  a food reward after every urination, the researchers say.

With help from UniServices, Matthews and Elliffe have met with representatives  of the New Zealand dairy industry, who are interested in the research as a  potential way of avoiding the herd reductions that may otherwise be necessary  to meet emissions targets.

A further application of the research may be to extract and reuse nutrients, such  as nitrogen and phosphorus, from the collected cow urine. At the University of  Auckland and elsewhere, there are researchers in fields such as chemistry and  engineering working on closely related problems.

“This is new science, what we’ve done here, so there are many ways to push it,”  said Matthews.