Prawns do feel pain, say scientists

Scientists have no qualms either, having long argued that crustaceans such as lobsters don't feel pain even when cooked live in boiling water.

But a British biologist is challenging this orthodoxy with a study suggesting that prawns, at least, do suffer when harmed.

Professor Robert Elwood dabbed acetic acid, the main ingredient of vinegar, on to the antennae of 144 of them.

The prawns reacted by rubbing the affected parts of their bodies for up to five minutes.

The reaction, he said, was exactly the same as that seen in mammals exposed to painful irritants.

"The prolonged, specifically directed rubbing and grooming is consistent with an interpretation of pain experience," he told New Scientist magazine.

Most biologists believe that simple invertebrates - animals with no backbones and limited nervous systems- cannot feel pain or experience-suffering.

Professor Elwood, of Queen's University, Belfast, rejects this argument on evolutionary grounds. The ability to suffer allows animals to learn from harmful experiences and avoid them in the future, he said.

His research has not, however, convinced other experts in the field.

Liverpool University's Dr Lynne Sneddon, who has investigated whether eels feel pain, said: "You could argue the shrimp is simply trying to clean the antenna rather than showing a pain response."

Dr Richard Chapman, of the University of Utah's pain response centre, said there was a difference between responding to an acidic chemical and actually feeling pain.

Most animal have sensors that react to irritants, he said, adding: "Even a single-cell organism can detect a threatening chemical and retreat from it. But this is not sensing pain."

Annette Pinner, of the Vegetarian Society, said diners should avoid eating lobsters even if the jury was still out on whether they can suffer.

She added: "The more information people have about the pain that animals feel and the way they are treated, the more likely they are to move to a vegetarian diet."