New research will determine if there is a better way of prioritising investigation of farms potentially infected with Mycoplasma bovis.
The Dairy Risk Assessment tool is an online questionnaire that helps a farmer to accurately understand the M. bovis risk on their farm. Used with their veterinarian, it can help a farmer make informed decisions about managing M. bovis risks and reduce possible spread of the disease on or off a farm.
The New Zealand Veterinary Association’s (NZVA) chief veterinary officer Helen Beattie says dairy farmers should talk soon to their veterinarian about using the tool.
“It’s a critical stage in the season when farmers may be considering buying or selling herds, sharemilkers may be considering moving to new contracts, and contract milkers and managers are considering next season’s job,” she says.
“Other than feeding raw milk, the main risk factor in M. bovis spread is stock movement. Farmers should talk to their veterinarian about a dairy risk assessment consultation before making decisions about buying a herd or moving cattle on or off their farm.”
During a consultation, farm management practices known to be a biosecurity risk are discussed with the farmer and recorded in the Dairy Risk Assessment tool by the veterinarian. The tool calculates the M. bovis risk assessment score and generates a risk rating of low, moderate or high.
The result is available immediately and can be shared by the veterinarian with the farmer, with recommendations to reduce risk.
Developed by NZ veterinary group XLVets and distributed by the NZVA, the tool has had almost a year of beta testing NZ-wide, and has been refined as understanding of the disease has developed. It uses known transmission risks, including findings from reports released by the Ministry for Primary Industries about the epidemiology and risk of M. bovis spreading in NZ.
The tool is used by registered veterinarians during onfarm consultations with farming clients.
“As a dairy farmer’s trusted onfarm biosecurity advisor, a veterinarian is the right person to reassure a farmer that their stock, moving on or off farm, will not be exposed to greater risk,” Beattie says.
“Veterinarians have the in-depth understanding of farm systems and animal diseases… required to recommend changes to a farm system that are practical and will reduce disease risk on-farm,” she says.
“The DRA is informative, affordable and faster and safer to carry out than surface-swabbing individual animals, which is required for laboratory testing.
“Individual negative (or not detected) test results are of limited value in understanding a herd’s true M. bovis infection status.”
Cattle sale biosecurity
Weaner sales are underway and Beef + Lamb New Zealand is reminding farmers to implement good onfarm biosecurity practices to protect their businesses from imported diseases.
BLNZ’s senior biosecurity advisor Will Halliday says while Mycoplasma bovis is front of most people’s minds on cattle diseases, any farm that has or is suspected of having M.bovis will be under a notice of direction (NOD).
This means animals cannot be moved from the property.
However, buyers should check all the cattle they are purchasing have NAIT tags and where possible ask the vendor directly about their NAIT records to ensure they are all up-to-date.
When purchased cattle arrive onfarm, the purchaser needs to receive them through the NAIT system and fill out the forms accurately and in a timely manner. They also need to make sure they have received an ASD form with the animals and this should be retained in the farm records.
As well as stock being moved through weaner sales, early dried-off dairy cows are often sent to grazing at this time of year and the same principles should apply, especially ensuring their records are up-to-date.