Emissions from burping cows 'higher than family car' - Climate Change, Environment - The Independent

A herd of cows belches out more climate-changing gas than a family car, a university researcher said today.
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He said efforts were being made to reduce the emissions, including providing different feed and using vaccinations, but added that they were in early stages of research.

And he said there could be problems with downsizing herds as working animals could end up being replaced by petrol-driven vehicles and a reduction in meat could lead to a "disastrous" increase in demand for fish and cereals.