One of the less predictable arguments to result from Brexit concerns the rights and wrongs of chlorine-washed chickens. Perhaps chlorinated-chicken-gate made many people feel temporarily smug about UK standards of animal welfare, compared with those in other parts of the world. Yet, at the same time, the Advertising Standards Authority upheld a 'Go Vegan World' advert with the headline "Humane milk is a myth" - a claim which suggests we do have much further to go before we can feel morally-superior about our treatment of animals. Veganism is on the rise, driven by animal welfare, health and environmental concerns. According to the Vegan Society, sales of vegan food increased by 1,500% last year and there are now more than half a million vegans in the UK, up from 150,000 ten years ago. Is veganism the next step in the march towards a more morally-enlightened and humane society? Or is it just a city-dwellers' fad, detached from the realities of food production, global economics and evolutionary biology? Whether vegans, vegetarians or meat-eaters, can our food production and consumption ever be compatible with animal welfare? Even if the language of animal 'rights' is unhelpful, do humans have a moral duty to avoid cruelty of any kind to other living things? Or is that an impossible goal while we prioritise the interests of Homo sapiens over the welfare of all other animals? Some believe that a society which is caring towards animals is more likely to be caring towards people. Others say that our conditioning from early childhood to embrace cuddly, friendly, talking animals has made us much too sentimental. As long as basic welfare standards are met, shouldn't important human needs be served by animals - including cheap chlorinated chickens?

Producer: Dan Tierney.