The arrival of cattle disease Mycoplasma bovis has been a wake-up call to farmers to keep their NAIT animal identification up to date, Federated Farmers policy and advocacy manager Gavin Forrest says.

Forrest was in Whanganui on April 13 to talk at a Whanganui Federated Farmers executive meeting about the disease, the difficulties of controlling it and repercussions if it is not controlled.

He doesn't know whether there are any Whanganui, Ruapehu, Rangitīkei or South Taranaki properties suspected to have the infection.

There are some in the North Island. Their names are kept private, because it's stressful for farmers to know they may have animals with the disease, and the testing process takes some time.


Mycoplasma bovis is a bacterial disease that can lie dormant in cattle but appear when they are stressed, especially at calving. It manifests as mastitis, pneumonia or arthritis and can't be killed by antibiotics.

It's not highly infectious and spreads through milk, semen and nasal fluids. Cattle with no visible signs of the disease can spread it.

It doesn't affect humans, and poses no threat to food safety.

It is hard to detect, and interested parties are working on a commercial test for it. Tests to date have arrived at false positives, and also false negatives.

The disease probably arrived in New Zealand in mid-2016, Forrest said, and was confirmed in a cattlebeast in Oamaru in July last year.

"Hopefully we can find out how it got in so we can reduce the risk of it getting in again."

Some countries live with it, but the Ministry for Primary Industries decided to try eradicating it. It is offering compensation to farmers whose herds are slaughtered.

At the moment there are 22 farms with infected stock, and the cull began in late March. So far there have been at least 85 claims for compensation.


The infected properties are in Canterbury and Southland, with one in Hawke's Bay.

Cattle, especially calves, are bought and sold and moved around a lot.

There is a another set of 700 properties that cattle from infected or possibly infected properties have been moved to. Some of them are at very low risk.

Properties at higher risk have been asked not to move any animals.

"It's causing quite a bit of stress for people. They are running out of feed and have had to bring more in," Forrest said.

The names of those "trace properties" have also been kept private, which he predicts will cause big debates about confidentiality.

People with closed and stable herds have fewer worries about the disease.

Having National Animal Identification and Tracing scheme (NAIT) records up to date would have helped a lot in dealing with it.

Forrest, a former Rangitīkei farmer, said NAIT was a pain in the neck but he is realising its importance.

People who suspect they have Mycoplasma bovis on their property are asked to ring the Ministry for Primary Industries on 0800 80 99 66.