The billionaire chicken farmer and racehorse breeder Bob Ingham has decided he will no longer rule the roost at the company that bears his name.

Mr Ingham, 81, yesterday put Inghams on the market - a move that is likely to mean control of the 94-year-old Australian company goes overseas.

While the firm, estimated to fetch about A$1.6 billion ($2.1 billion), would be a natural fit for its biggest rival, Baiada, the competition regulator would be unlikely to approve further concentration of a sector already dominated by the two family-owned groups.

Instead, bids are likely to come from private equity groups or overseas food multinationals. Last night CP Group of Thailand was emerging as frontrunner.

It will be the second pay day for Mr Ingham in the past five years, with the sale of his Woodlands stud to Dubai's Sheikh Mohammed bin Rashid al-Maktoum. reaping A$460 million in 2008.

John Hexter, one of the management team handling the daily business of Inghams for many years, said Mr Ingham - who was not available for interview - had ''decided that now is the time to seek a suitable buyer for the business''.

Mr Ingham's children, Robby, Lyn, Debbie and John, are not directly involved in the operation of the company.

Yesterday the company said it had sold A$2b worth of chicken in the past 12 months but little else is known about its finances. Its accounts are shielded by a rule introduced in 1995 that exempts some large family-owned companies from filing annual accounts.

The Inghams started in the chicken business after their father, Walter, died in 1960. The brothers were left a chicken and pig farm company, which was valued at about A$100,000 but on which they had to pay A$40,000 in death duties. They built the chicken business to become one of Australia's biggest.

The brothers loved racing and bought Woodlands stud in 1986. It became the largest racing and breeding operation in Australia.

Bob Ingham continued to run Woodlands after the death of his brother Jack in 2003. He stepped up his involvement at yearling sales, spending more than A$46m at the Inglis Easter sales in the five years after his brother's death.

The sale to Sheikh Maktoum was a walk-in, walk-out deal. It included a number of studs, the centrepiece being Woodlands in the Hunter Valley. There were also the stables at Warwick Farm and around the country, and more than 1000 horses including brood mares, stallions and racing stock.

In more than 40 years in racing, the Inghams owned 84 group one winners but never won a Melbourne Cup. They have had an interest in seven Golden Slipper winners, the final being Forensics in 2007.

Octagonal won the Sydney three-year-old triple crown of the Canterbury and Rosehill Guineas and the AJC Derby and a Cox Plate. The stud careers of him and his son Lonhro have continued the Ingham legacy.

The brothers were inducted into the Australian Racing Hall of Fame in 2004.

- Sydney Morning Herald