Bovine tuberculosis (TB) has turned up in a small dairy herd near Matamata, in the Waikato.
The identification of a cow showing symptoms of bovine TB infection late in 2016 triggered a programme of responsive testing of dairy cattle and the slaughter of a small number of calves, OSPRI - an organisation formed to eradicate the disease - said.
OSPRI national disease manager Kevin Crews said the animal was found at a routine post-mortem inspection at a slaughter facility.
The infection was confirmed with laboratory testing and herd tests continue to be conducted on the farm concerned.
OSPRI immediately introduced measures to restrict animal movements in the area, it said.
The area had been considered TB-free, with no recent history of infection.
The outbreak is considered to be a stock movement-related and not by way of the usual transmission through possums. The area has no recent history of TB infection.
Crews said the property concerned had been temporarily restricted to reduce the risk to cattle and deer in the area while testing and treatment of the herd was completed.
The herd will undergo repeated TB testing until there are two whole-herd tests, six months apart, where no infection is confirmed.
The final whole-herd test will involve a parallel blood test. The herd will remain classified as infected status until that time, he said.
Waikato TBfree committee chair Chris Irons said that while the recent infection is not good news for the region, with the assistance of OSPRI and local herdowners the issue can be dealt with effectively.
"As the TB testing programme proceeds, I urge all landowners to co-operate with contractors in completing their tests and allowing access to their properties," Irons said.
A spokesman for OSPRI said TB outbreaks were not uncommon in New Zealand. As at the December 31 last year, 43 herds had been tested positive for the disease, down from 1900 or so in the 1990s.
OSPRI is a not-for-profit limited company through the mergert of the Animal Health Board and National Animal Identification and Tracing (NAIT). Its shareholders are DairyNZ, Beef and Lamb New Zealand and Deer Industry New Zealand.