Sheep to Be Genetically Engineered to Produce Less Methane

Farmers are looking to reduce their greenhouse gas emissions in a weird and wonderful way: using genetically engineered, low-methane sheep.

A project named 'Breed for CH4nge' has been announced in the U.K., pledging £2.9 million—$3.7 million—to breed sheep to emit as little methane as possible, helping farming get closer to net zero emissions.

"We have to move faster in terms of farming being a solution to climate change, and play our part in the UK's 30 percent methane reduction by 2030 targets agreed during COP26 [a U.N. climate change conference]," Phil Stocker, chief executive of the National Sheep Association,—a partner in the project—told the FarmingUK website.

Methane is a greenhouse gas, which is around 80 times more powerful as a heat-trapping insulator in our atmosphere than CO2 over a 20-year period.

Sheep—along with other livestock, like cows—emit methane as they burp and fart, contributing hugely to global greenhouse gas emissions. Worldwide, livestock raising is responsible for 57 percent of all food production carbon emissions, according to a paper published in the journal Nature Food, and between 11 and 17 percent of global greenhouse gas emissions.

In the U.K., 50 to 60 percent of a sheep farm's carbon emissions come from methane emitted by the sheep themselves, according to Farmers Weekly.

This project is led by genetics company Innovis and funded by the U.K. government's Farming Innovation Fund, and is a three-year initiative that plans to measure the methane emissions of 13,500 sheep in 45 flocks, to determine the efficiency of the sheep as of now.

They then plan to analyze this data, as well as data on the size of the sheep's rumen [part of the stomach] and microbiota [microscopic organisms in the gut], to rank the sheep in terms of methane emissions, feeding efficiency, and health. DNA sampling will also allow researchers to study the relationships of these traits with the sheep genome.

The highest scorers on this Estimated Breeding Value (EBV) scale will be selectively bred over multiple generations to create sheep that are still healthy and useful to farmers, but produce less methane than before.

"Through this work the consortium will identify ways to reduce our emissions but also ensure we do this in a way that maintains the wide range of sustainability traits inherent in many of our flocks," Stocker said. "Importantly the project is designed so that, in time, lessons will be able to be adopted by any breed and breeders and I see that as key to improving our genetics without diluting our genetic pool."

New Zealand has been breeding sheep to be low-methane emitting since 2007, with their third-generation selectively bred flock already emitting 16 percent less methane than before. The New Zealand Agricultural Greenhouse Gas Research Center states that there is no evidence that any of the important traits of the sheep have been compromised in the breeding for lower emissions.

New Zealand has also been developing low-methane cattle since 2020, as well as trialing specialized livestock feed to reduce methane emissions, and methane inhibitors to prevent the animals from producing the gas.

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