Meanwhile, with farmers culling cattle from herds hit by drought, Dargaville's largest employer, the Silver Fern Farms meat works, has handled an additional 3000 animals between October and February.
Silver Fern Farms' chief executive Keith Cooper said markets were absorbing the increased supply well.
"This is normally a peak production period and we are coping with current livestock flows across our plants," he said.
Industry body DairyNZ ran two drought management meetings in Whangarei on Monday to provide farmers with advice.
DairyNZ Northland consulting officer James Muwunganirwa said with little rain since December, pasture covers were low and, with a shortage of supplementary feed, some farmers had moved to milking once a day and were either drying off or had dried off.
Despite recent rain, there is no drought relief in sight for farmers, with no significant rain forecast for the rest of this month.