The wholesome rural image promoted by Bernard Matthews, already damaged after its Turkey Twizzlers were damned as “cheap, processed junk food” by Jamie Oliver and banned from schools, may be tarnished further by the outbreak of bird flu on the group’s turkey farms.

The family-run company, established in 1950, markets itself as a producer of “healthy, high quality turkeys”. Its founder, Bernard Matthews, sold insurance before he decided to become a turkey farmer and paid £3,000 for a dilapidated mansion named “Great Witchingham Hall” and 36 acres of land near Norwich for his fledgling company’s new headquarters.