Navis confirmed in April that it had taken a majority stake, without detailing the size or the price paid.

Recent filings to the Companies Office show a Hong Kong company affiliated to Navis holds three-quarters of the shares, while among the existing shareholders Guthrie's Bay Trustees owns 14.2 per cent, Murray Valentine holds 7.1 per cent and the family of Jeff Winmill holds 3.2 per cent.

Guthrie previously held about 76.6 per cent of the shares, Valentine 18 per cent and Winmill, who is general manager of the company's MainFeeds business, held 5.3 per cent.

All three remain involved in the company as directors or managers. Navis reportedly spent about $300 million to take control of the business.

The deal required Overseas Investment Office approval but the OIO didn't immediately confirm that approval had been gained.

Mainland Poultry produces one-third of New Zealand’s eggs, through its Zeagold Foods unit, which has the Woodland and Farmer Brown caged and free-range egg brands, processes eggs products for the food industry, and produces a range of animal feeds through MainFeeds.

It operates as a vertically integrated business and the feed unit had been set up as part of that but now sold to other customers and exported.

Phil Latham, a Sydney-based partner at Navis, said in April that Mainland required between $40 million and $80 million of capital expenditure including the cost of phasing out its battery cages in favour of larger colony cage systems or free-range to comply with new animal welfare rules.

He said Mainland's know-how in egg production could be exported to markets in Asia. Navis said at the time it planned to "transform Mainland into the pre-eminent agribusiness in the Oceania region with strong export linkages into Asia."

Navis has offices in Asia and Australia and has previously invested in poultry businesses in UK, Europe, Thailand and China.