FEARS that electronic identification (EID) of sheep could hit trade were voiced at the show.

David Airey, chairman of the West Riding branch of the National Farmers' Union (NFU), said he had "grave concerns" about the technology which will be introduced in six months time.

He understood a test of a scanner at a local auction mart only had an 82pc success rate - which would not only affect local hill farmers but the lowland farms who buy their stock.

Similar problems could also bring trade to a halt, affecting abattoirs and the entire market place.

Mr Airey said: "I have grave reservations that EID will be a bridge too far and we are going to suffer the consequences and food security could also be hit."

He said if lambs were held up because of EID problems they could gain fat, through no fault of the farmer, which could put housewives off buying the meat.

The big problem at the moment was that not enough details of the rules and regulations are known. He believed EID would lead to some farmers quitting sheep, particularly where they have other options.

The sheep sector had many older farmers, some of who don't have computers or even electricity. "They have generators but with the fluctuation in voltage they are not compatible," said Mr Airey.

Peter Kendall, NFU national president, said: "EID is coming but we have to fight for all the flexibility we can to get round all the problems."

Lowland commercial fatteners were saying they could not see it working and asking what was the point of spending money if they could not use it.