The police officers immediately abandoned the pursuit to tend to the injured animals and help the farmer, Symonds said.
The driver kept going but crashed a short distance down the road. The occupants fled on foot but another police unit managed to catch three of five young men.
When officers stopped a car seen leaving the area a short time later they found a young man hiding in the boot.
A dog handler and his dog found the last alleged offender soon after. Police who stayed with the injured cows called a vet but the farmer was able to euthanise them quickly and humanely, Symonds said.
Five youths, three aged 15 and two aged 14, were expected to be held in custody overnight and to appear in the Kaikohe Youth Court today.
Police are supporting the farmer and will seek reparation on his behalf for the loss of his stock.
Yesterday's chase is likely to further focus attention on youth crime in the Kaikohe area.