CNN
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The cow’s amazing ability to sustain itself by eating nothing but grass is one of the marvels of nature, but it comes at a cost.
As grass ferments in the rumen — one of four compartments in the animal’s stomach — it naturally produces methane, a greenhouse gas 28 times more potent than CO2, although shorter lived in the atmosphere. That methane is released through belching and farting, and on average, a single cow can produce about 200 pounds of it per year. The gas is also released by manure, and livestock accounts for about a third of human-related methane emissions, which are collectively responsible for about 30% of global warming.
Some farms that feed cows in yards already use food additives that help reduce methane production in a cow’s stomach, but they have downsides, such as variable efficacy and the need to be constantly supplied, which is difficult if the animals are free to roam.
A vaccine could be an alternative, and the Pirbright Institute in the UK, a virology lab focusing on livestock, is leading a three-year study to develop one. “The appeal of a vaccine as part of the solution is that it’s a very well adopted, common practice, with infrastructure able to do this already, and people know about the benefits of vaccination for animal health generally,” says John Hammond, director of research at The Pirbright Institute.
The international effort is supported by $9.4 million from the Bezos Earth Fund, the Amazon founder’s philanthropic entity to fight climate change, and also involves the UK’sRoyal Veterinary College, and AgResearch, an agricultural innovation lab in New Zealand.
“The expectation is that it would be familiar — it would be like other vaccines,” says Hammond. “Best-case scenario, it’ll be a single-dose vaccine that an animal would receive relatively early in life that continues to have an effect, and the target is an absolute minimum of 30% reduction in methane emissions.”
Scientists have been working on the idea of a “cow fart vaccine” for well over a decade, according to Hammond, but without tangible results as of yet. “There’s been significant investment in different countries in trying to develop this unusual vaccine, in that it’s not necessarily for the benefit of the animal, but it’s for the benefit of the emissions that the animal might produce,” he says. “There’s no product, but there’s scientific literature that suggests it can work and will work.
“To work, the vaccine would need to produce antibodies that bind with the bacteria in the rumen that produce the methane, and stop them from doing so.”
However, he adds, developing it is a very complex challenge, because antibodies — proteins that are produced by the immune system after receivinga