Navis, which has offices in Asia and Australia, planned to "transform Mainland into the pre-eminent agribusiness in the Oceania region with strong export linkages into Asia," it said in a statement. Mainland had solicited proposals after hiring ANZ Bank to advise on options for the business, which requires capital investment to meet new welfare rules for its 1.2 million layer birds.

Mainland needs to replace equipment to meet the requirements of the Animal Welfare (Layer Hens) Code of Welfare 2012, which calls for the staged phasing out of battery cages in favour of larger colony cage systems or free-range. Managing director and a founding partner Michael Guthrie has said existing shareholders weren’t getting any younger and “may want to have a pathway to liquidity”.

No price was disclosed and Mr Guthrie didn't immediately return calls. The Australian newspaper reported the price was about $350 million. The Navis statement also didn't say what size stake it is buying, although founding shareholders of Mainland "will retain a significant shareholding in the business" and senior managers will be retained. The deal needs Overseas Investment Office approval.

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.

Navis is no stranger to poultry, with what it calls "significant portfolio investments in chicken and duck operations in the UK, Europe, Thailand and China". In 2016 it sold Golden Foods Siam, one of Thailand's largest exporters of "higher value breaded and roasted chicken products", to Brazil's BRF for an enterprise value of US$360 million, having taken a controlling stake in the business in 2009. It teamed up with Rabo Capital in 2013 to sell duck processor Bangkok Ranch for 5.7 billion Thai baht, having bought that business in 2007 for an enterprise value of 4.3 billion baht.

Navis manages about US$5 billion in equity capital, invested across the Asian region. It was advised by Ernst & Young and Bell Gully on the Mainland deal.

The Australian also reported that Navis is interested in buying Freshmax, controlled by Maui Capital and being marketed by Goldman Sachs. Freshmax had a net profit of $2.17 million in the 12 months ended 30 September last year on sales of about $219 million. It imports, wholesales and distributes fresh produce including apples, pears, stonefruit, kiwifruit and avocados to a wide variety of countries.