Australian dairy cooperative Bonlac Foods has reported a 51% fall in full-year net operating profit to A$18m (US$11.8m).

"Bonlac had a tough year due to under-utilisation of our plants and the effects of our hedge book," Bonlac chairman Noel Campbell was quoted by Reuters as saying.

The company said export sales revenues for the year to 30 June fell 20% compared to the previous year, mainly because of lower commodity prices and the rising Australian dollar.

Bonlac has recently struck a deal with New Zealand dairy giant Fonterra that Bonlac said will lead to annual cost savings of between A$35m and A$38m.

Under the deal, Fonterra is to increase its stake in Bonlac from 25% to 50%, as well as assuming day-to-day management of Bonlac.