A Mid-Canterbury property has been confirmed to have mycoplasma bovis, for the first time this year.
Photo: RNZ / Rebekah Parsons-King
The infection was found in a spring-calving herd during routine bulk tank milk (BTM) screening.
Two further herd tests also returned positive results.
The Ministry for Primary Industries (MPI) is working closely with the farmer to investigate, manage and remove the infection, with a restricted notice in place to prevent animal movement.
A small number of other properties which have had cattle movements from the farm in the last year, are also under a restricted notice.
Ministry for Primary Industries (MPI) M bovis eradication programme director Simon Andrew said the cause of the infection was not yet known, though it was likely linked to animal movements.
But Andrew said it was not cause for concern.
"The BTM screening programme provides confidence that M bovis is not widespread, and we remain on track for eradication, as shown by our very low rate of case finds from testing.
"Based on previous years, we know autumn and spring are our peak periods for detections picked up from the BTM screening and it is not unexpected to find infected farms at this time."
BTM screening takes samples each month at the point of collection as part of the normal milk collection process.
Samples are then screened for M bovis antibodies and results indicate whether an on-farm investigation is needed.
Recent MPI analysis of screening data found detection of the infection is higher in the first 30 days of milking.
As a result, from July to September, fortnightly BTM screening will be implemented.
The confirmed result is the first for 2022, and brings the current number of properties with active infections in New Zealand to two.
The disease was first detected in a South Canterbury farm in 2017, and has since been cleared from 271 properties, with more than 176,000 cattle culled.