A new study discovered kangaroo farts release into the air substantial amount of methane. The team of researchers found that the amount of methane released per kangaroo varies but can easily produce 45.5 pounds of methane in a year, similar to the amount of methane produced by one adult horse.

According to University of Wollongong's Adam Munn, who co-authored the study, the lesser the animal eats, the longer the food remains in the foregut which gives more time for the bacteria to digest. The lesser the animal eats, the more methane it produces.

"Kangaroos are not mysteriously low methane-producing creatures, but herbivores with an active methane-producing microbe community," said University of Zurich's Marcus Clauss, the study co-author. The researchers focused on methane due to its contribution to climate change.

The kangaroos at the Fowlers Gap Research Station in New South Wales were fed alfalfa in two ways: one group was given a restricted diet while the other group was free to eat all the alfalfa they wanted. The team measured the food intake and fecal excretion of the kangaroos to determine how much methane is produced through the fart. The team also looked into the efficiency of the animals' digestive system in reducing the gas.

A lab in Switzerland looked into the kangaroo feed and feces' nutrient content. Scientist Michael Kreuzer focused on how much the animals digested side to side with the amount of methane produced. They found that well-fed kangaroos produced less methane compared to the others who ate less.

Changes in the breeding process and dietary intake are few options the researchers are looking into to solve the current problem.  

However, Kangaroo Industries Association of Australia's executive officer John Kelly is unconvinced of the recent findings. He mentioned that kangaroos are still deemed environmentally friendly.

"There's a whole range of reasons to eat kangaroo; harvest is the only mechanism to control the population, which is essential to manage grazing pressure and encourage a whole lot of plant diversity. The industry has been steadily growing for a number of years," said Kelly.

The new study is in contrast to the 2014 study that revealed kangaroo gut has 'unique microbes' that reduce methane production. The new study was published in the Journal of Experimental Biology.