Mycoplasma bovis

In July 2017, the bacterial infection Mycoplasma bovis was found in cattle in the Oamaru area of the South Island. With the support of farmers, industry bodies and local communities, MPI is working hard to locate the disease, contain it and, if possible, eradicate it from New Zealand.

Information for consumers

Mycoplasma bovis is a bacterium that causes illness in cattle, including udder infections (mastitis), abortion, pneumonia and arthritis. It does not infect humans and presents no food safety risk.

The disease is found worldwide and is not considered a disease of relevance to trade by the World Animal Health Organisation (the OIE). There are no regulatory restrictions for meat and dairy products due to Mycoplasma bovis.

Extensive national surveillance is underway to determine the distribution of the disease in New Zealand. To prevent further spread of the disease, the Ministry for Primary Industries has put in place strict controls and is developing plans with farmers for animals from the known infected farms.

On this page:

Situation report

The current number of 'active' Infected Properties (quarantined under movement restrictions) as at 17 May 2018 is 38.

The regional breakdown of total Infected Properties (IPs) from the start of the response is below. The number of 'active' IPs (some have since been depopulated, cleaned and had their restrictions lifted) is in brackets.

  • Waikato (near Cambridge) – 1
  • Hawkes’ Bay (near Hastings) – 1
  • Manawatu – 1
  • Canterbury – 3 (2 active)
  • North Canterbury (Cheviot) – 1
  • Mid-Canterbury (Ashburton) – 7
  • South Canterbury/North Otago – 12 (10 active)
  • Otago (Middlemarch) – 2
  • Southland (Winton, Lumsden, Invercargill, Gore) – 13

All infected properties are under quarantine controls restricting the movement of stock and equipment on and off those farms to contain the disease.

Map showing properties under legal controls and surveillance

This map shows properties (as at 10 May 2018):

  • under Restricted Place Notices
  • under Notices of Direction
  • under consideration for a Notice of Direction
  • identified as at risk through the tracing of animal movements.

Properties under legal controls and properties under surveillance – Map [PDF, 154 KB]

Presentation given to farmer meeting in Pahiatua 17 May 2018 [PDF, 1.3 MB]

Culling infected farms

In late March, the Ministry for Primary Industries (MPI) made the decision to cull all cattle on the 28 Infected Properties identified at that time in New Zealand. The cull is a critical measure to control the spread of the disease.

The depopulation is expected to be completed by the end of May, with the exception of a small number of farms where it may not be completed until June or July as we are working to accommodate the circumstances of the individuals impacted by the cull. All affected farmers will be compensated for their verifiable losses.

What is Mycoplasma bovis?

Mycoplasma bovis is a bacterium that can cause a range of quite serious conditions in cattle including mastitis that don’t respond to treatment – pneumonia, arthritis and late-term abortions.

The disease may be dormant in an animal causing no disease at all. But in times of stress (for example, calving, drying-off, transporting, or being exposed to extreme weather) it may shed bacteria in milk and nasal secretions. As a result, other animals may be infected and become ill or carriers themselves.

It does not infect humans and presents no food safety risk. It is an animal welfare and productivity issue.

This is the first time it has been found in New Zealand. The bacteria is an Unwanted Organism under the Biosecurity Act 1993.

Mycoplasma bovis is not listed with the OIE (the world animal health organisation) and doesn't present a trade risk for New Zealand animal products. Internationally, the disease is managed by farmers through:

  • good biosecurity practices on their farms
  • careful selection of replacement stock and breeding bulls
  • keeping herds in a good state of health.

No food safety risk

Mycoplasma bovis is not a food safety risk. It is a disease that affects animal welfare and production. It affects only cattle, including dairy cows and beef cattle. It is common in many food-producing nations where infected animals that aren’t showing symptoms are processed for human consumption.

Cattle that are slaughtered in New Zealand as part of measures to control Mycoplasma bovis are processed in line with standard procedures. Before leaving the farm, they are assessed by vets to confirm they are fit for transport. At the processing plants, MPI veterinarians assess the health of each animal before slaughter.

Any animals that are sick, severely injured, or have any medication in their system are not processed for human consumption. This is a requirement of New Zealand law. All animals are also examined after slaughter to ensure the meat is safe and suitable for consumption.

How is it spread?

On farm: Mycoplasma bovis is spread from animal to animal through close contact and bodily fluids, for example, mucus and also milking equipment. Calves can be infected through drinking milk from infected cows. Urine and faeces are not regarded as significant transmitters of the disease, but the bacterium does survive for longer in a moist environment such as in piles of moist faeces or wet bedding material.

Off farm: The disease is mostly spread through movement of cattle from farm to farm. Movement restrictions preventing the spread of stock off infected properties are therefore the most appropriate measures to contain this disease.

Farm equipment may play a role in the spread of the disease, especially equipment that comes into direct contact with infected animals such as artificial imsemination (AI) instruments.

Vehicles pose very little biosecurity risk. It is absolutely safe for trucks to move from infected farms to other properties. All infected farms are under strict legal controls under the Biosecurity Act which require comprehensive cleaning and disinfection before leaving the property.

Advice for farmers, contractors and transporters

Look out for and report Mycoplasma bovis

Look out for signs of the disease and report to your vet or MPI on 0800 80 99 66.

What to look out for - Mycoplasma bovis poster [PDF, 636 KB]

Practice good on-farm biosecurity

Keep NAIT and other animal movement records up to date

It's critical that you maintain up-to-date and accurate NAIT (New Zealand’s cattle and deer tracing system) and animal movement records. Accurate record keeping helps us track animal movements and locate any that could be affected.  


The work to contain the disease – the response

MPI, animal production industry bodies, veterinarians and farmers are working together on a large-scale biosecurity response to the disease. 

We're focusing on determining the scale and distribution of the disease across the country, containing any risk of spread from infected properties and ultimately making a decision on the best way to manage it in future. 

We are confident Mycoplasma bovis is not well established in New Zealand. The testing of milk from every dairy farm in the country, combined with our surveillance work tracing every possible movement of animals from infected farms, has shown the disease is not widespread but is limited to a network of farms connected by animal movements. 

To control the disease, we're issuing 2 types of legal notices to farms that are affected and farms that are suspected of being affected. The notices – Restricted Place Notices and Notices of Direction – are to restrict the movement of any risk goods, including animals, out of these properties. To make sure the requirements of the notices are followed, MPI follows up all incidents of non-compliance.

Testing and surveillance

A large operation is underway to build a picture of where the disease is and help decide how it should be managed. MPI is testing animals on known infected farms and trace properties (farms where animals or risk goods have been moved from infected properties, or which have supplied animals to infected properties).

MPI is also testing samples supplied through regional vet laboratories from cows with mastitis. With the support of the dairy industry, we're testing milk from all productive dairy farms across the country. Under the National Surveillance Programme, 3 samples are being analysed from each farm – one from the bulk tanker milk and 2 samples of discard milk from the sick cow herd.

MPI is a significant way through the testing process. We expect the National Surveillance Programme will show whether the disease is in more farms than those associated with the 2 known clusters.

Mycoplasma bovis is a complicated disease to rule out and we need to have absolute confidence in all test results. We need to be able to give farmers and the New Zealand public certainty. This means test results can take time to analyse.

Culling animals to prevent further spread

In October 2017, MPI made the decision to remove and cull animals from affected properties in the Oamaru area to prevent further spread of the disease. We made this decision after doing tens of thousands of tests.

The operation was completed at the end of December 2017.

All premises, transportation vehicles, and equipment involved in the de-population followed a strict decontamination and disinfection process to reduce any risk of the disease spreading.

Work is now underway to clean and disinfect the affected farms and repopulate them. 

Depopulating all remaining infected farms 

On 26 March 2018, MPI made the decision to cull all cattle on the 28 infected farms in New Zealand. This will involve some 22,300 animals either going to slaughter at processing plants or being culled on-farm if they are not healthy enough for processing. The cull is a critical measure to control the spread of the disease.

This will be a planned process that will take weeks or months to complete. MPI will work closely with affected farmers to plan the logistics of this large exercise. All affected farmers will be compensated for their verifiable losses. Once farms are de-populated and cleaned, it will be possible to start re-building a disease-free herd from scratch.

We're taking this action now as extensive milk testing and farm tracing has provided confidence that Mycoplasma bovis is:

  • not endemic in New Zealand
  • limited to a network of farms connected by animal movements.

Culling these animals is now the appropriate action.

Farms that are under Restricted Places Notices (RPN) or Notices of Direction (NoDs) aren't being directed to cull their herds because infection hasn't yet been confirmed. MPI will work with those farmers to develop individual management plans for each of these properties – until a decision on whether to eradicate Mycoplasma bovis or move to long-term management is made.

Industry support for depopulation 

DairyNZ, Federated Farmers, and Beef+Lamb New Zealand support MPI’s decisions. They also recognise that this is a difficult time for the farmers involved.

The industry organisations believe that the measures are necessary to protect all New Zealand cattle farms from the disease. New Zealand is one of the few countries where Mycoplasma bovis is not found naturally. Because of this, the industry groups support measures to keep it that way.

Technical Advisory Group (TAG) and pathway analysis reports

MPI convened a group of technical experts to review its response to Mycoplasma bovis. The report from the group includes a secondary addendum report produced after the group reconvened when the disease was found in Southland.

The ministry carried out an analysis of 7 potential ways Mycoplasma bovis could have entered New Zealand. The pathways report reached no conclusion about how the disease arrived here. MPI continues to investigate the means of entry.

Note: Redactions have been made to the TAG and pathways reports consistent with provisions of the Official Information Act 1982 (OIA). Where required, the Ministry for Primary Industries has considered the public interest when making decisions on the information being withheld.

We have always said with this disease outbreak that it is unlikely we will be able to determine the exact pathway. We remain of that view – however, the report provides insight into pathway risk to support future management decisions.

Welfare support

MPI is working closely with industry organisations, the Rural Support Trust, and government agencies to support people who are most affected. We’ve prepared a fact sheet with information on looking after yourself if you’re affected by the Mycoplasma bovis outbreak.


Affected farmers can claim compensation where MPI’s exercise of legal powers (under the Biosecurity Act 1993) has caused them a verifiable loss, either:

  • as a result of damage to or destruction of the person's property, or
  • as a result of restrictions imposed on the movement or disposal of the person's goods.

Learn more about Biosecurity Act compensation
Mycoplasma bovis compensation claim form – User guide [PDF, 446 KB]

Previous 2018 media releases

  3 May 18 April
16 April 28 March  26 March 
23 March 5 March 23 February
15 January 12 January 9 January

2017 media releases

12 December    
15 November  8 November 12 October
2 October 8 September 29 August
23 August 11 August 7 August
4 August 1 August 31 July
28 July 27 July 25 July

DairyNZ resources

Beef + Lamb NZ resources

Who to contact

If you have questions about Mycoplasma bovis:

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