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.
Eating food of bovine origin contaminated with the agent of BSE, a disease of cattle, has been strongly linked to the occurrence of vCJD in humans.
Bizarrely though, I can give blood in the UK and do so every time I go back.
The ban here by the NZ Blood Service was introduced in 2001 and is estimated to have cut donor numbers by 10 per cent. The service will not accept blood from people who spent more than six months in the UK between 1980 and 1996.
When the ban was first introduced it was going to be for 10 years, but that has now been extended indefinitely. The ban ensured the safety of the New Zealand blood supply, NZ Blood Service said.
I had hoped that after all this time (and showing no signs of having contracted BSE), that the ban would have been lifted by now, but sadly not.
But the service said scientific data has shown that some people harbour the infectious agent of vCJD and as a result some have developed vCJD and some have accidentally transmitted the disease through blood donations.
Despite me not being able to give blood, I urge everybody else who can to do so. It only takes about 30 minutes of your day. Who knows, you could be saving somebody's life - vegetarian or carnivore.