I've certainly met a few mad cows in my time, but from memory I don't think I've ever eaten one.
But mad cow disease is stopping me from giving blood in New Zealand. Now I hope my opening line hasn't offended anybody, but it's meant to illustrate that I find this situation a bit amusing.
I've been vegetarian for about 38 years and haven't eaten any meat products in that time, but because of the UK's bovine spongiform encephalopathy (BSE) - or mad cow disease - outbreak of the 1990s I can't give blood here. BSE can lead to the human equivalent Variant Creutzfeldt-Jakob Disease (vCJD) - a rare and fatal human neurodegenerative condition.