The vegetarian musician keeps a flock at his property, but he refuses to send them to an abattoir and they are there until they die of old age,
In an interview for Radio 4's The Food Programme, to be broadcast on Sunday, he points out that few people ever see elderly sheep and are surprised by their appearance.
"I live on a sheep farm so we shear the sheep. But they die of old age and you know what, it's kind of embarrassing because none of the other farms have got old sheep," he said. "They're all gone before they're old – they just die like we do. It's life, it's death, it's what happens.
"We just give them a good life and I take the wool from them. but it can be embarrassing. People say 'look at the state of your sheep' and I say yes they're very old and you know there is only one alternative – send them to the knacker's."
In an interview with presenter Sheila Dillon, Sir Paul talks about his vegetarian lifestyle and his desire to encourage more people to try eating less meat.