Dairy herds are on the move as sharemilkers change farms to take up new contracts, coinciding with the end of the milk production season.
The flurry of moves at the end of the dairy season as sharemilkers re-locate their cows to new farms is commonly known as "gypsy day". The switch can also cause a stir in small rural schools as rolls fluctuate.
Councils sometimes receive a flow of complaints from motorists upset about the effluent being spilt on to roads from stock trucks moving the cows to new homes.
Spills and complaints have already begun in the largest dairying region, Waikato.
Waikato Regional Council senior transport planner Isy Kennedy says some of that can be avoided if farmers prepare their stock for the trip.
The council says truckies can do their bit by using effluent disposal sites set up for the purpose and motorists should be patient when following stock trucks.