The commercial diagnostic tool for the bacterial disease would hopefully speed up lengthy official tests, but its release has more hurdles yet to pass. The tool is not a do-it-yourself test but farmers could commission veterinarians to carry it out.
The Ministry for Primary Industries (MPI), which oversees the official tests, is among a partnership developing the tool with commercial laboratories and industry groups.
MPI lately had to reassure farmers it was responding to compensation claims as fast as it could in return for cows being culled in an attempt to prevent the disease from spreading. Farmer impatience has also been directed at the pace of testing for the difficult to diagnose disease. Equally, farmers have acknowledged their record keeping needed to improve.
Before the tool is released it must meet sampling guidelines, a testing strategy and possibly an accreditation programme to ensure it is accurately used and interpreted.
MPI response director Geoff Gwyn said since the discovery of M. bovis in New Zealand last year the partnership had been working hard to provide farmers and other people with better diagnostic tests to assist in detecting the cattle disease on their farms.
“However, while testing options and solutions are becoming available, we have identified that interpreting a one-off test result, even at the herd level, in isolation to other factors, is challenging and carries inherent risk for farmers. The tests currently available will lead to a significant number of farms being falsely identified as positive and farms that may be real positives being missed.
“That’s why we are developing robust processes, including a testing strategy and sampling guidelines which may form part of an accreditation programme.”
The partnership behind the test programme includes the NZ Veterinary Association (NZVA), Beef + Lamb NZ, DairyNZ, Dairy Companies Association of NZ, Federated Farmers, AsureQuality, MilkTest NZ, Livestock Improvement Corporation, New Zealand Veterinary Pathology, SVS Laboratories and Gribbles Veterinary Pathology.
NZVA chief veterinary officer Helen Beattie said the partnership was focused on helping farmers who were dealing with the many uncertainties around the disease.
“All parties in this partnership are acutely aware of the need for a robust on-farm solution for farmers who are concerned about Mycoplasma bovis. All parties are working urgently on developing this tool, and all the elements needed to support it.”
An accreditation programme will likely consider test results and other factors such as herd management, animal health and record keeping, including NAIT records. They will be used to inform farmers of the likely risk of M. bovis in their herd.
MPI is continuing to test milk from every dairy farm, in a programme nearly completed, alongside its surveillance work tracing movement of animals from infected farms.
“We acknowledge that some farmers may be disappointed they don’t have access to a commercial diagnostic tool now to give them some certainty about whether their animals, or animals they may be purchasing, carry the infection. However, it’s critically important that we don’t rush this – we have to get it right,” said Gwyn.
Thirty properties have tested positive for the cattle disease and last month MPI decided to cull 22,000 cattle from them. The disease is confirmed at one property each at Hawke’s Bay and Canterbury, six in Ashburton, 10 in South Canterbury/North Otago, two in Otago (Middlemarch) and 10 in Southland.
The bacterial disease causes illness in cattle including mastitis, abortion, pneumonia, and arthritis. M. bovis is hard to treat and once infected animals may carry and shed it for long periods of time with no obvious signs of illness.
Farmers with cows showing signs of mastitis are still being urged to contact veterinarians who will pass on samples to diagnostic labs for M. bovis testing, in a cost covered by MPI.