Cows are being potty trained to help reduce the ammonia emissions produced by their waste.
Scientists have discovered calves can learn how to use a toilet quicker than very young children and it’s hoped it will help cut down air pollution and create more animal-friendly farms.
On a farm where cows freely relieve themselves as they graze, the accumulation and spread of waste often contaminates local soil and waterways.
This can be controlled by confining the cows in barns, but in these close quarters their urine and faeces combine to create ammonia, an indirect greenhouse gas.
While the ammonia produced in cow waste does not directly contribute to climate change, when it is leached into the soil microbes convert it into nitrous oxide, the third-most harmful greenhouse gas after methane and carbon dioxide.
Agriculture is the largest source of ammonia emissions, with livestock farming making up over half of that contribution.
Researchers from Germany and New Zealand found a process dubbed MooLoo training can teach calves to relieve themselves in return for treats.
“It’s usually assumed cattle are not capable of controlling defecation or urination,” said animal psychologist Dr Jan Langbein, from the Research Institute for Farm Animal Biology (FBN) in Germany.
“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?”
The team started off working backwards by rewarding the calves when they urinated in the latrine.
They then allowed the calves to approach the latrines from outside when they needed to urinate.
“You have to try to include the animals in the process and train the animals to follow what they should learn,” said Dr Langbein. “We guessed it should be possible to train the animals, but to what extent we didn’t know.”
To encourage latrine use, the researchers wanted the calves to associate urination outside the latrine with an unpleasant experience.
“As a punishment we first used in-ear headphones and we played a very nasty sound whenever they urinated outside,” said Dr 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.”
Over the course of a few weeks, the research team successfully trained 11 out of the 16 calves in the experiment.
Remarkably, the calves showed a level of performance comparable to that of children – and superior to that of very young children.
Dr Langbein is optimistic that with more training this success rate can be further improved.
“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,” he said. “They are not all the same.”
Now the researchers know how to potty-train cows, they want to transfer their results into real cattle housing and to outdoor systems.
Dr Langbein is hopeful that in a few years “all cows will go to the toilet”.
The full study is published in the journal Current Biology.