The Ministry for Primary Industries’ testing programme has identified one new property as positive for the bacterial cattle disease Mycoplasma bovis.
The newly identified property is a Van Leeuwen Dairy Group farm which was already under a Restricted Place notice under the Biosecurity Act.
Response Incident Controller Stephen Bell says the disease doesn’t always present symptoms and often doesn’t show up through just one test.
The ministry therefore has developed a testing protocol which tests herds up to three times at three to four week intervals.
Testing like this, over two to three months, “gives us the confidence we need that we have definite results for each farm,” Mr Bell says.
“This latest detection is evidence of that protocol working.
“It has meant there has been a long period of disruption and uncertainty for farms that are being tested but we have to be absolutely thorough in diagnosing positive and negative farms. It’s important for New Zealand that we take that time to get accurate results”, he says.
The testing programme for Mycoplasma bovis has resulted in over 26,000 of the planned 39,000 tests being completed by the ministry’s Animal Health Laboratory at Wallaceville.
These tests have been focused on the infected properties, stock movement traces from and to those properties, and the neighbouring properties. No adjacent properties have yet been identified as infected.
Officials have also been taking a multi-layer approach to testing to find how far Mycoplasma bovis might have spread.
District-wide surveillance in Waimate/Waitaki has been part of this. Bulk and discard milks were collected from approximately 260 farms in the area and tested. All these results are now back and no further infection outside the Van Leeuwen Group has been found on farms in this area.
There has been a nationwide testing programme, too. Samples of mastitic milk have been collected from regional labs across the country for testing.
Approximately 2,300 samples have been received but tests have not identified infected farms elsewhere in New Zealand.
Mr Bell says taken together, these results are encouraging, suggesting the ministry’s surveillance plan is working “and this disease is not spreading in the local area around the infected farms and is not widespread across the country”.
While the sampling and testing programme continues, the ministry is also preparing for what might happen next.
This involves preparing plans for the different possible scenarios. Eradication is one of the scenarios.
“We hope to have a clear picture by mid-October,” Mr Bell says.
“If samples continue to test negative for Mycoplasma bovis and if the evidence is pointing to the infection being contained to the current properties and not having spread wider, we would expect to have sufficient confidence to assess whether this disease can be eradicated.”
“We know this is an enormously stressful time for the impacted farmers and also for the wider farming community. We are carrying out all our work with urgency to limit the impact on the farming community as much as possible.
More information on Mycoplasma bovis can be found HERE.