The highly infectious cattle disease Mycoplasma bovis has been cleared from Northland.
The affected properties can now get back to farming as normal, according to Ministry for Primary Industry's M.bovis programme director Stuart Anderson.
Mycoplasma bovis is a bacterium that can cause a range of serious conditions in cattle – including mastitis that doesn't respond to treatment, pneumonia, arthritis, and late-term abortions. It has no cell wall so is resistant to penicillin and other antibiotics.
It does not infect humans and presents no food safety risk. However, it has a serious effect on animal health.
The cattle disease may be dormant, causing no symptoms. But in times of stress such as calving, drying-off, transporting, or extreme weather, the animal may shed bacteria in milk and nasal secretions, infecting other cattle.
Anderson said only nine properties are still infected, all in Canterbury, which is where the disease was first confirmed in July 2017.
More than 250 properties have now been cleared of infection in a major operation by MPI, Dairy NZ and Beef & Lamb NZ over the past three years.
"There are 45 properties under Notice of Direction movement controls to stop the risk of spread, while we progress them through testing to ensure their cattle do not have M. bovis. None are in Northland," he said.
Considered very low risk of having M. bovis, 100 properties are getting precautionary tests under Active Surveillance without restrictions to provide assurance their cattle are not infected; eight of these properties are in Northland.
At its height, M.bovis was confirmed on 26 properties in Northland and many more were put under movement control to restrict the potential for the disease to spread.
Anderson said the M.bovis programme provides a wide range of support to farmers, their whānau and workers affected by the disease.
Support includes compensation for financial loss and reimbursement for operational costs involved in meeting the programme's requirements such as extra transport costs, mustering and feed supplies. The programme also provides support through organisations like the Rural Support Trust, which has been heavily involved in supporting affected farmers. The DairyNZ Beef + Lamb New Zealand Compensation Assistance Team (DBCAT) was also set up to help farmers prepare their compensation claims.
Overall the numbers of M.bovis infections are notably lower than they have been in previous years.
"We are looking harder than ever and finding fewer instances of infection. This indicates we are getting in front of the disease and closer to our goal of eradication," he said.
"We're on track to achieve eradication,
"But there's still more work to do. We expect to find more infected herds as we actively look for those final pockets of infection, so everyone needs to remain vigilant."
The movement of infected cattle into other herds and calves being fed infected milk are the two main ways M. bovis is spread in New Zealand.
Whenever cows, calves or bulls from different farms or herds mix there's a risk of spreading infection, Anderson said.
When buying stock, farmers should always check the source of cattle and their health history with their stock agents.
Anderson said keeping National Animal Identification and Tracing (Nait) records up to date is important for all farmers. It helps track animal movements faster and prevents the spread of M. bovis infection to other herds.
All animal movements, even between properties a farmer owns, should be recorded, he said.
The programme introduced national surveillance tools, including bulk tank milk screening and beef surveillance, which are helping to provide confidence that M. bovis is on track to being eradicated.
"These tools play an important role looking for infection outside the tracing network. They'll also play a significant part in providing the confidence needed to declare New Zealand M. bovis free," he said.
The bulk milk tank screening programme takes samples each month at the point of collection as part of the normal milk collection process.
"This is screened for M. bovis antibodies and detects where we need to take a closer look. This screening tool helped find the cluster of infected farms in Mid Canterbury.
"Our monthly bulk tank milk screening of dairy farms across New Zealand continues to indicate there is no widespread infection in the dairy sector.
"Historical data shows we will see more detections during the drying-off period in autumn and winter and at the start of lactation for winter milking herds so it will not be unexpected to [see] some increase in numbers during this period,'' he said.
The beef surveillance programme screens beef cattle not connected to known infected properties, alongside tuberculosis testing.
Testing results from more than 22,100 beef cattle on more than 10,100 farms has found no infected beef farms.
"These results give us increasing confidence that M. bovis is not widespread in the beef or dairy sectors," Anderson said.
Dairy NZ, Beef and Lamb NZ have developed biosecurity guidelines to help farmers to prevent pest and diseases entering their properties.
These are available on their industry websites.
Farmers are strongly encouraged to discuss biosecurity with their veterinarian, especially as winter grazing approaches, and to develop a biosecurity plan for each farm.