I've seen the battery farm horror - and Jamie's right

The supermarkets are obviously running scared, because they have paid for full-page advertisements claiming that they are ever so kind to the chickens they sell.

"Sainsbury's is working hard to continually improve welfare standards", Jamie's own employer tells us. The Co-op has taken a different but equally desperate approach: "We believe that happy and healthy chickens result in moist and flavoursome meat ... Just the thing when you're looking for a little tenderness."

None of these ads are illustrated, as logically they should be, with images of the birds scratching happily in the great outdoors. Instead, we're presented only with the finished item, fresh out of the oven. For British consumers do not respond well to being reminded of the live animals they eat.

It is this aversion that has permitted the vast and disgusting industry of factory farming to flourish in this country, where we eat 750 million birds a year, only two or three per cent of them free range. We choose not to look inside these sheds, where cruelty to animals is practised on such a gigantic scale, preferring instead to agitate about fox-hunting.

As it happens, I do know what I am talking about. I spent the year between school and university working, 12 days out of 14, in a battery chicken farm that produced the eggs for hatching on to broilers. The world inside these sheds was hellish: stinking, hot, dimly lit, deep in shit. The birds were all demented, often smothering each other in panic, and whenever one became injured, furiously cannibalising it. One of the regular jobs was to pull out the birds with broken legs and wring their necks. On my first day, I was shown a tip for dealing with tough cockerels - put both feet on a broomstick across their necks and pull the legs hard with both hands. Sometimes the whole head came off.

It perhaps wasn't the best use of a gap year - when I got to university, everybody else seemed to have been studying history of art in Florence - but it has stayed with me. Even now, whenever I'm having a bad time - having to watch a play, for example - I have only to think that at least I'm not back on the chicken farm to feel better. And I have never knowingly bought factory-farmed chickens.

Hugh and Jamie have modest enough aspirations for change. Fearnley-Whittingstall says he would count it a success if 20 per cent of chickens became free-range. Oliver wants consumers to pay just £1 more per bird, which would transform the way they are farmed. But to achieve anything, they will have to overcome our crazy consumer culture where we will pay for designer labels but not better quality food.