LAMBS in Scotland could be seen in woollen overcoats to endure the winter months if an innovative idea from New Zealand takes off.

Some farmers in Scotland use plastic covers to protect newborn lambs through their vulnerable first week, but New Zealand ''woolover'' pioneer David Brown claims plastic covers are second best.

Mr Brown, who farms near Christchurch in South Island, lost a large number of lambs throughout the 1970s and 1980s, but the catalyst for action came in 1992.

''Farmers lost about two million lambs because of the freezing conditions in 1992.

''I hit on the idea of a fabric made from felted wool, which covers the newborn lamb apart from its head and legs.

This allows the scent of the lamb to get through to the mother, so that the bonding between sheep and lamb is not affected.

An important condition imposed on the coverings by the RSPCA was that if the farmer was unable to catch the lamb to remove the woolover, it would come off by itself as the lamb grows.

The woolover can be recycled by the wool-processing companies as dirty wool.

Each covering costs about NZ$2.50, around #1, but it saves a lamb that could be worth between #10 and #20 when they are sold, ''and that is a big increase in a farmer's income,'' said David Brown.

A rather drastic field trial was carried out, where, just before a severe storm, one group of 40 lambs was clothed in the woolover, while another group did without.

Only five of the uncovered lambs survived.

The woolovers are being sold in Britain through an agent based in Wiltshire, but so far sales have been slow to take off.

Mr Brown said that many sheep producers in Britain lamb their sheep indoors, or delay lambing until the weather is warmer.

One farmer who used plastic covers last year is Alistair MacLennan, who farms near Grantown-on-Spey.

He was surprised at the ferocity of the weather in the first two weeks of May. He deliberately delays the lambing season to try to ensure better survival rates.

''Seeing the forecast was for more bad weather, I put polythene jackets on every newborn lamb.

''They were not so good for the older lambs, because the coats smell, and the sheep could not get the scent of the lambs properly, and rejected their own lambs,'' he said.

Mr MacLennan, who worked on a sheep farm in New Zealand several years ago, said that he did not lose a single lamb because of hypothermia. However, he is sceptical about the woolover.

''The plastic jackets worked well, the lambs felt warm underneath them, and the jackets broke down in daylight and fell off after about 10 days.

''I think that woollen coverings could not keep out the rain, and wet lambs could get cold more easily,'' said Mr MacLennan.

But David Brown said that the woolover had definite advantages over the plastic coats.

''Plastic covers are available in New Zealand, but the shimmering of the cover in daylight, and the noise of raindrops hitting the plastic also puts the mother sheep off.

''We overcame potential problems of waterlogging with the woolovers by increasing the grease content, and we found that the air pockets between the lamb's body and the wool covering kept heat in very effectively, even when the covering was wet.

''I would invite Mr MacLennan to try some woollen coverings, to see that they are better,'' he said.

Woolovers are also being developed for sheep which have been newly shorn. Several crofters and farmers in the Highlands and Islands have been caught out by bad weather in recent years, just after shearing, with sheep dying from pneumonia-like diseases caused by the cold.

The problem seems to have been made worse by the more widespread use of electric clippers, which give a much closer cut.

A woollen overcoat could be the answer for shivering sheep, until their own woollen coats grow again.