The Ministry for Primary Industries (MPI) is responding to the detection of the cattle disease Mycoplasma bovis in a dairy herd in South Canterbury.
The disease is commonly found in cattle globally, including in Australia, but it's the first detection of it in New Zealand.
The Ministry's Director of Response, Geoff Gwyn, says Mycoplasma bovis does not infect humans and presents no food safety risk. There is no concern about consuming milk and milk products.
"This bacterial disease can, however, have serious effects on cattle including udder infection (mastitis), abortion, pneumonia and arthritis.
"Right now we're working with the farmer to contain the disease to the affected farm and treat the animals showing symptoms. We are very appreciative of his support in this work."
Mr Gwyn says MPI has put legal restrictions in place to stop any movement of stock from the property while the scale of infection is determined.
MPI was advised of sick cattle at the property last Monday and Mycoplasma bovis was confirmed by the Ministry's Animal Health Laboratory late on Saturday (22 July).
"Fourteen cows have tested positive for Mycoplasma bovis and approximately 150 cows on the property have clinical signs that indicate they may be affected. MPI is now tracing movements of animals on and off the property to ascertain if other properties are at risk.
"Right now, we do not know when or how the disease entered New Zealand," Mr Gwyn says.
Farmers are advised to contact their vet if stock show unusual levels of mastitis, abortions or present with arthritis or pneumonia.
Mycoplasma bovis only affects cattle and has no effect on other animals.