A Shetland pony breeder is offering a £200 reward for any information that may lead to the safe return of Jade, a six-year-old in-foal miniature piebald mare, who went missing from her field in Ashbury, near Lambourn last month.

“We first realised Jade was missing when we arrived to check the ponies early on Saturday22 February,” explains Bernard Cooper, who has been breeding miniature Shetlands with his wife Carmel for the past 15 years.

“She was living in our winter paddocks in Ashbury, about five miles from our stud in Longcot, with 11 other in-foal mares when she disappeared. We believe she was lifted over the fence as the gate was padlocked and the fence secure.

“At just 28in in height she was the smallest of the mares in the paddock, which was probably why she was chosen. She is also the last of the mares due to foal so the thief probably didn’t realised that her bit of a tummy was a developing foal rather than her just being fat.”

The Coopers are extremely concerned for the welfare of Jade and her unborn foal, but despitecontacting the police, other Shetland breeders, their local horsewatch group, press and radio, as well as putting up hundreds of posters in their local area they have had no news.

“About six years ago we had two ponies stolen, but luckily the police had a tip-off and they were returned to us within a couple of weeks. Jade has now been missing for almost a month and we are extremely worried about her.”

Jade is due to foal around the end of July and Bernard hopes she will be foundbefore she suffers any ill effects.

“Jade is a friendly person and has quite unusual markings, so should be easy to recognise. She has a white whole between her eyes, a white band above her nearside hoof and white back legs, plus a white splash on her offside.”

Anyone with information is asked to call the Thames Valley Mounted Section (tel: 01908 686075) or the confidential CrimeStoppers hotline (tel: 0800 555111).