While each kg of red meat produces far more greenhouse gases than pork or poultry, equal amounts of different meats have different nutritional values. Looking at the greenhouse gases emitted to produce the recommended intake of 12 key nutrients, “beef performs best,” Prof Michael Lee of UK-based Rothamsted Research told a meeting of the Global Roundtable on Sustainable Beef (GRSB) in Kilkenny last week.
He spoke as a new University of Oxford-led article in the journal Nature showed that the share of livestock products, especially red meat, would need to decline in the diets of the average consumer by 2050 if we are to bring climate change under control (see ifj.ie/nature). Both studies suggest a shift in focus towards achieving balance between the nutritional needs of a growing global population and the ability of farmers and the environment to deliver a matching mix of foods.
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Methane
Lee used the globally accepted calculations developed by the Intergovernmental Panel on Climate Change (IPCC), which emphasise methane gas from ruminants. But Tim McAllister, a microbiologist with the Canadian department of agriculture and former IPCC member, said this could change.
“Since I’ve been with the IPCC, the global warming potential of methane has changed three times. It keeps going up,” he explained. However, the latest knowledge points in the opposite direction. Not only does methane break down in the atmosphere after 10 to 12 years, its carbon also comes from a shorter cycle than that buried in oil or coal for millennia. “Methane was previously a plant before the animals consumed it, which is very different from the ancient carbon associated with fossil fuels,” McAllister said. Sara Place of the National Cattlemen Association in the US said that the short-term, cyclical nature of methane means its climate impact could be addressed by stabilising its emissions at an acceptable level – which still represents a big challenge.
Science-based targets
McDonald’s vice-president for sustainability Keith Kenny said his company was now setting “science-based targets to reduce greenhouse gas emissions” across its supply chains and restaurants. Producers in 10 countries supplying more than 80% of its beef will have to enter sustainability programmes applying GRSB criteria. Those in Brazil and Canada are in place and Ireland is next, Kenny said. As a buyer of beef and dairy products, Kenny said both sectors should align in the way they approach climate change. “If we talk about it in different ways, we just give space to the sceptics,” he said.
In Ireland, Kepak’s own finishing farm has reduced the age at slaughter by 13% in the past three years through improved nutrition.
“It’s two to three months less that the animal is producing methane,” said project manager Aoife Ryan. Kepak’s agriculture manager and suckler farmer Sarah said sustainability objectives should be translated into attractive targets for farmers, such as calving interval. “At the end of the day, it comes down to the bottom line,” she said.
Seaweed in feed
Pip Band of Meat and Livestock Australia said her organisation had identified growing legumes, improving genetics and feeding seaweed as some of the top options to reduce the climate impact of the country’s beef farms. Red algae added to feed have shown potential to reduce methane emissions by 80% to 90%, she said, but getting it to animals in a commercial way is the challenge.
McAllister agreed that chemical and seaweed-based additives were promising, but “they’re still difficult to deliver to animals outside”. A vaccine under development in New Zealand could be more practical, but “it is still at the science stage and not near commercialisation,” he added. Ian McConnel of the environmental NGO World Wildlife Fund (WWF) said that livestock currently accounts for 14.5% of greenhouse gas emissions from human activities, and over half of these come from beef. This means that cutting emissions from fossil fuels alone won’t put an end to climate change. “We don’t get to +2°C if we don’t address the livestock challenge as well,” he said.