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2nd March 2022

Mooloo: The Scientists Potty Training Cows to Save the World

Cattle farming has a huge environmental impact, but seems unlikely to disappear any time soon. Find out how scientists are potty training cows to lesson their impact on climate change.
Mooloo: The Scientists Potty Training Cows to Save the World
Peter van der Sluijs @Wikimedia Commons

Researchers have managed to successfully toilet train 11 out of 16 cows, in an attempt to lesson the environmental impact of their urine.

The team of scientists, based at the University of Auckland in New Zealand, trained the calves to use a latrine, which they nicknamed the ‘mooloo’, up to 80% of the time. Released in September 2021, their research could be expanded in the future to reduce the significant global damage caused by cattle farming.

Unsplash @jeancarloemer

The Climate Killer Conundrum

A single cow can produce about 30 litres of urine a day. When this urine is combined with faeces, it can produce ammonia.

Ammonia can lead to eutrophication, a form of water pollution characterised by excessive nutrients in the water supply, as well as causing acid rain. It can also taint water with nitrates to produce nitrous oxide, a greenhouse gas and airborne pollutant.

Although the environmental impact of urine is not as significant as that caused by the belching and farting of cattle, nitrous oxide still made up 5% of greenhouse gases in the UK in 2019.

In addition, farming practices that are designed to benefit cattle welfare increase the amount of ammonia released into their environment. In attempting to toilet train cows, this team of researchers hoped to allow farmers to ensure good conditions for their cows, whilst reducing ammonia’s environmental damage.

How to Potty-Train a Cow

For the first step of the experiment, scientists were confined to the ‘mooloo’, and rewarded with a sweet, molasses-based liquid every time they urinated. This helped them form a positive association with urinating in the latrine.

The cows were then moved out of the latrine, but had access to it from an alley through an animal-activated gate. If they urinated in the latrine, they were rewarded with the same molasses-based liquid, but if they urinated in the alley, they were sprayed with water for three seconds as a form of negative reinforcement.

Diuretics were given to the cows to make them urinate more frequently, as the scientists had to limit the duration of experiments due to ethical guidelines put in place to protect animal welfare.

The researchers involved in the project have estimated that it is possible to potty-train a cow to a similar level of a 2-4 year old child. Out of the 16 cows studied, 11 managed to consistently use the latrine correctly, using it to urinate 83% of the time. The other cows managed to use the latrine with lower, varying degrees of success.

Can Cows Using Toilets Change the World?

Although the sample size is small, these results are promising, and the global scientific community seem fairly confident these results could be replicated. The primary issue is likely to be the scaling of technique for use in the cattle industry – it may be possible to toilet train a small group, but it is likely to be far more difficult to train an entire herd of cattle, which can number in the hundreds.

In addition, only urination was investigated, which only leads to a small fraction of the environmental impact caused by cattle. The research team were fairly confident they could expand the results to defecation, but the worse climate-offender is belching, which this technique cannot address.

However, the enormity of the meat and dairy industries means that even small improvements can have a big impact. The researchers claimed that capture of about 80% of cattle urine in latrines could lead to a 56% reduction in ammonia emissions. It would also improve the cleanliness of cattle living space, which can only improve the cows’ welfare.

Whilst more and more people are turning to veganism, the vast majority of society are not going to ditch meat and dairy products any time soon. In the short term, at least, potty-training cows could help solve this particular climate conundrum.



Emma Hattersley

Emma Hattersley

Editor: Science and Technology Section

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