Three more farms infected by Mycoplasma bovis have been confirmed in Canterbury and Southland by the Ministry for Primary Industries (MPI), bringing the total to 17 properties.
The discoveries come after the MPI released further information about its testing and tracing regime designed to contain and eradicate the spread of the cattle disease.
Ministry officials expect more farms will test positive as a result of disease testing being ramped up, including as many as 30 additional properties alone from an infected Ashburton farm.
They are working out how far the disease has spread in New Zealand. Tests will be carried out including for three samples of milk from every dairy farm in New Zealand starting February 1 with results expected over the next two months.
MPI will also trace animals moved from properties under restricted place notices. MPI staff have followed up almost 1000 leads for possible links to infected properties, with 39 under restricted place notices as tests continue.
The confirmed tracing of animal movements takes several days and involves using records from the National Animal Identification and Tracing (NAIT) scheme, animal status declarations, trucking dockets and interviews with farmers.
This is followed by genome sequencing, which worked out whether the strain of Mycoplasma bovis was the same across all infected farms. This takes several months as it involves growing the bacterium from samples.
MPI incident controller David Yard said MPI had changed its approach from reporting all new cases of Mycoplasma bovis through the media to only issuing press releases when there were major new developments, such as a positive detection in a new area or region.
“We expect that more properties will become positive as our tracing and testing programmes continue to ramp up. From one farm in Ashburton alone, we anticipate tracing some 30 additional properties.”
Two of the new cases are on Southland farms and one is in Ashburton.
Yard said the new properties were detected through tracing activities and were connected to existing properties positive with M bovis.
Farms infected with the disease are mainly in the Oamaru area with additional positive properties in Hawke’s Bay and Southland confirmed last December. Another two properties were identified in the Ashburton area this month.
All of the infected properties are under restricted place notices under the Biosecurity Act. The legal controls restrict the movement of stock and equipment on and off the farms to contain the disease.
Federated Farmers national president Katie Milne called for “patience and a dose of realism” as speculation around Mycoplasma bovis’ origins grew.
Milne said it was adding more stress to worried farmers at a time when the situation was still unfolding, with MPI and the wider industry working hard to contain the disease.
“Of course there is curiosity among farmers and the media as to how M. bovis started as it has never been detected before in New Zealand to our knowledge.
“This is a complex disease and there is a significant amount of resources going into testing and surveillance carried out by MPI and the industry.”
Milne was still hopeful that it could be eradicated with farmer support.
“Farmers have a role to play around traceability by ensuring NAIT tagging and recording of all cattle and deer. We advise also an on-farm disinfecting policy, buffers on boundaries and quarantine of newly introduced stock to their properties.
“This should become part of a new best practice of making your farm a fortress when it comes to biosecurity.”
Agriculture and Biosecurity Minister Damien O’Connor said he had great sympathy for farmers caught in the outbreak, who faced tough decisions to protect their livelihoods.
“There is a willingness out there to do whatever it takes to eradicate M bovis. This remains our focus.”
He visited farmers involved in the outbreak in Winton, Southland, after previously visiting affected South Canterbury properties before Christmas.
“Farmers have shared their concerns about the speed of the response, started under the previous National Government in July, and how we can contain the spread of the disease.”
Mycoplasma bovis is not a food safety risk for humans and is a disease that affects animal welfare and production. It only affected cattle, including dairy cows and beef cattle, and was first confirmed last July on two farms in South Canterbury.