A theoretical study last year funded by the Government's Foundation for Research Science and Technology (FRST), rejected the concept of engineering a sheep with only a fine underwool, said Agresearch scientist Andy Bray. The "naked" sheep concept was mooted as a possible way of helping the lamb and mutton trade. "We found that the trait could be bred naturally in sheep breeds which retain it from their ancestors in the wild," he said.

``If there's a market for sheep which put less effort into growing wool and more into producing meat, then the trait can be taken from breeds such as the Wiltshire."

New Zealand has more than 3000 Wiltshire sheep, which do not have wool around the head and crutch, and shed their fine, bulky fleece annually if left unshorn.