Australian retailing billionaire Gerry Harvey's NZ Thoroughbred Holdings has posted a wider full-year loss as the owner of Westbury Stud builds its line-up of stallions.

The net loss widened to $NZ4.9 million in the 12 months ended June 30, 2014, from $3.97m a year earlier, according to the company's annual report.

Revenue rose 1.6 per cent to $4.39m and other income fell 15 per cent to $2.8m, for a total gain in income of 0.7 per cent to $7.2m.

Expenses rose 8.8 per cent to $12.2m including a 55 per cent jump in agistment, or pasture fees, to $2.6m.

The results amount to small beer for Harvey, whose bloodstock interests include Australia's thoroughbred auction house Magic Millions, which has one of that country's richest competitions in the Magic Millions Race Series.

Harvey's $A1.55 billion ($NZ1.63b) fortune, built up via the Harvey Norman retail chain, ranked him 21st in the 2014 BRW Rich List.

NZ Thoroughbred's assets include Westbury Stud, which runs stallions and yearlings at a 86-hectare property at Karaka, south of Auckland and a 121ha property near Matamata that houses more than 180 mares, according to its website.

Harvey took control of Westbury, which was established by businessman Eric Watson, in 2009 when he bought out property developer Michael Tololi.

NZ Thoroughbred's auditor noted in the annual report that the company's ability to be a going concern depended on the continued financial support of Harvey's GH Westbury Trust.

As at June 30 last year, the company owned shares in eight stallions, up from seven a year earlier, including Makfi, whose yearlings sold for up to $A200,000 in Sydney last year and up to $200,000 at the Karaka Premier sales in New Zealand.

Makfi's stud fees run to $17,500 plus GST.

"This is a long-term game and that's Gerry's approach," said Westbury general manager Russell Warwick.

"It is a five to six year cycle of investment Gerry is putting into New Zealand, based on building a stallion line-up and getting results. The last six months are telling us we're well on track."