Mycoplasma bovis

What you need to know about the Mycoplasma bovis infection.

M. bovis Technical Advisory Group Report

The independent Technical Advisory Group (TAG) has provided its latest report on the M. bovis Programme. The report shows that the Programme is making multiple changes to ensure we all have the best chance of getting rid of this disease from New Zealand.

Farmers are our priority and insights from the independent TAG group confirms the programme is continuously improving for farmers, and for affected farmers. Those farmers are under enormous stress - undergoing testing, movement restrictions or in the worst-case scenario and at worst having their herd depopulated. We are committed to reducing this stress and the overall impact of the Programme on farmers.

The TAG supports the changes made following both the DairyNZ-commissioned review and MPI review of the backlog that happened earlier this year. While the TAG says it is too early to see the full impact of changes made, there are positive signs of improved performance - including fewer infected farms, and more farms with high-risk exposure testing clear.

The TAG have made further recommendations for action. DairyNZ supports the recommendations for continued work on ELISA test validation, ongoing review of the backlog impact, beef surveillance and options for defining and declaring we’ve gotten rid of this disease. We still have more work to do and the Programme will continue to focus on these recommendations in the coming months.

DairyNZ continues to work closely within the M. bovis Programme to ensure positive outcomes for farmers. By sitting at the table, we are committed to ensuring farmers are getting value for money, costs are scrutinised, performance is monitored, processes are continually improved and that farmers views are represented.

Managing service bulls

The highest risk for the spread of M. bovis is the movement of infected animals from one herd to another. Bulls who have been in contact with infected cows, and then moved to another herd are a risk for the spread of infection.

Testing for Mycoplasma bovis in bulls

M. bovis is not an easy disease to test for on an individual animal basis, especially in animals not showing clinical signs. The tests available are designed to either work at a herd level, to show animals are having immune responses to circulating infection in the herd, or on animals actively shedding the bacteria. Animals only shed M. bovis intermittently, and immune responses to infection vary. Therefore, negative results on a single bull can’t be interpreted to mean that that animal is not infected, and a positive result on the herd test does not mean that the bull has M. bovis either. The best indicator of whether an animal may be infected is the health status of the herd the animal comes from.

Interpreting the test results

Animals from dairy herds that have been tested and where infection is not detected can be considered low risk for spread of infection. Herds with test results that indicate evidence of M. bovis infection will receive directions from MPI on the management and movement of animals, and owners of bulls that have been there will be contacted. Ensuring your animals' NAIT movements are recorded will assist in this situation.

Bulls

It is essential that the bulls are properly identified and NAIT records are completed promptly for all movements.

Recommendations for management of bulls:

Bulls arriving on farm – all ages

Bulls should arrive properly identified and accompanied by details of their movement history and health status of the herd they have been in. Make sure you let the vendor or agent know that you will be expecting to be provided with these details.

On arrival the bulls should be held separately from the main herd for at least 7 days to enable an assessment to be made of their health status, and for any procedures such as drenching to be completed. If you have any concerns about the health of the bulls, contact your veterinarian before you mix the bulls with the herd. Minimising the number of herds bulls are sourced from will make this process easier.

Bulls leaving the farm

If the bulls are leased, then talk over the options with the owner.

R2 bulls – once mating is finished these bulls should be sent directly to slaughter. It is important that they go from the farm to the slaughter premises directly and not via saleyards or some other intermediate stopping point. If they are being held for further use (mating in autumn 2020, or spring/summer 2020/2021) then the recommendations for R1 bulls should be followed.

R1 bulls – these bulls may be a risk for the spread of infection. The best indicator of the level of risk from these bulls is the health status of the herd the bulls have been running with - pay particular attention to the herd’s levels of mastitis and lameness.

All farmers must ensure their NAIT records are correct and up to date.

Using imported or local semen
The Import Health Standard (IHS) that regulates the importation of semen into New Zealand recognises that semen is a potential pathway for M. bovis. The IHS has controls in place around the husbandry and health status of donor bulls to reduce the risk of introducing disease.

Tests for the disease in semen exist but are not particularly reliable. M bovis can survive freezing, and antibiotics routinely used in the processing of frozen semen may not be completely effective in killing mycoplasmas.

What can farmers do?

Ask your semen supplier:
- What kind of assurance can your semen supplier give that insemination of your herd will not lead to M. bovis on your farm?
- Have the donor bulls been tested for M. bovis?

Weaned calves

Many farmers will now be buying, selling, and/or moving weaned calves to grazing. There are steps you can take to help protect your animals from M. bovis.

Sending weaned calves to grazing
Stock movements are the highest risk for spreading M. bovis.

Protect your calves from exposure to M.bovis by preventing nose to nose contact with cattle from other sources. Discuss your expectations with everyone who is involved in the transport and care of your calves once they leave the home farm.
- Transport - Ask your transporter to avoid mixing your calves with other cattle in holding yards or on the truck.
- NAIT - Make sure all your calves have their NAIT tags in their ears and promptly record all movements.
- If your calves are being grazed on a property with cattle from other sources, measures must be taken to completely prevent your calves from coming into contact with them.
- Visit the Biosecurity for Grazing Properties page to learn about the risks and solutions for specific areas on the grazing block.
- Graziers can use this Communication Plan to help them get organised and protect their property.

Buying and selling weaned calves
Stock movements are the highest risk for spreading M. bovis.
- Know the source
  - Purchase from as few sources as possible.
  - Deal directly with the source farm or via an agent.
    - Ask if the farm is subject to any bovistracing by MPI.
    - Ask about the stock trading practices for the farm.
    - Ask about the source of all milk fed to calves on the farm.
    - Ask if all stock movement records are up to date and recorded in NAIT.
    - Ask about cow and calf health on the farm for the past two seasons, and use the pre-purchase checklist.
  - NAIT
    - Purchase only calves with NAIT tags and promptly record all movements.
  - Transport
    - Ask your transporter to avoid mixing calves with other cattle in holding yards or on the truck.
  - Quarantine
    - Keep purchased calves isolated from your main group for seven days and monitor them for signs of disease.
  - If you are selling, be prepared to provide the information above to people buying your calves.

Bulk milk testing recommences

The Ministry for Primary Industries have announced that all dairy farms supplying milk will have a bulk sample tested from July 1. Tests will be carried out once a month and will run indefinitely.

Protect your farm and animals

You can protect your farm and animals by undertaking some simple biosecurity practices on farm.

Complete the Biosecurity WOF, developed with farmers and vets, work through this guide and develop on on-farm biosecurity plan.

The biggest risk for spread of M. bovis is through direct animal contact, focus on preventing contact with cattle from other herds. If purchasing new stock, read the pre-purchase checklist.

Complete NAIT records

Always complete your NAIT records and make sure if you have had movement over the last month they are correctly recorded. Knowing where your cows have been is crucial to understanding and preventing the spread of disease.

Grazing

If moving animals for grazing - check the grazing property’s biosecurity health status. All M. bovis infected properties are under Restricted Place Notices under the Biosecurity Act. Ensure that the grazing property has good biosecurity measures in place, such as preventing your stock from having nose to nose contact with stock on the farm or neighbouring properties.

Fencing

Check your boundary fences are secure

Put in double fencing at least two metres apart to stop nose to nose contact between you and your neighbour’s stock. Permanent is best but in the short term it can be simply putting a reel up if your neighbour’s stock are going to be in the adjacent paddock.

Feed

If bringing in supplementary feed - there is no risk of M. bovis infection from bringing in hay or baleage from uninfected farms. If the feed is coming from a farm under a Notice of Direction or a Restricted Place Notice, confirm that it meets any conditions on the Notice.

Contractors and machinery on farm

The risk of spreading M. bovis bacteria between farms on machinery is low. However, it is good biosecurity practice to have a “clean on, clean off” policy for both machinery and people, which will protect your farm business from weeds, pests, and diseases. You should expect machinery to arrive clean to your property, and expect the machinery to be cleaned before it leaves your property for the next job. Disinfection should be used after cleaning on equipment and boots/gear that have been in contact with stock and/or effluent. Check out the cleaning and disinfection poster for more information.

What is Mycoplasma bovis?

is a bacterial disease
is commonly found in cattle all over the world, including in Australia
it does not infect humans and presents no food safety risk. There is no concern about eating meat, milk and milk products
it does lead to serious conditions in cattle and therefore constitutes an animal welfare and productivity issue
it spreads from animal to animal through close contact. Between farms it spreads through the movement of animals that are infected but may not be showing symptoms. It is also potentially spread on contaminated equipment and the feeding of untreated milk to calves. It is not windborne.
while some of the conditions can be treated, affected cattle will always be carriers of the disease
the disease does not affect sheep or cause illness in goats although it is thought goats could carry and transmit it.

How does it affect cows?

untreatable mastitis in dairy and beef cows
severe pneumonia in up to 30% of infected calves, starting as a hacking cough
ear infections in calves, the first sign typically being one droopy ear, progressing to ear discharges and in some cases a head tilt
abortions
swollen joints and lameness (severe arthritis/synovitis) in all ages of cattle
know the signs to look out for, download the 'Signs to look out for' poster. If stock show unusual levels of mastitis, abortions or present with arthritis or pneumonia, contact your vet.

Working to eradicate M. bovis

The decision has been made to continue to focus on eradicating M. bovis from New Zealand. We believe that we have a chance to get rid of it for good by undertaking phased eradication.

Phased eradication will mean continuing to trace all potentially affected cattle, and testing and culling those herds with infected animals in them. This will continue until regular surveillance finds no further evidence of the disease. By phased, we mean that it will take place over a number of years. We expect to do most of the eradication work in 1-2 years. It will be done in cooperation with affected farmers to allow flexibility around timing of culling to offset production losses.

Read more about the decision to eradicate and what it means for you.

M. bovis compensation

If you are a farmer directly affected by M. bovis, we have a a team that can help you with compensation.

The DairyNZ and Beef + Lamb NZ Compensation Assistance Team can help you with:

understanding whether you are eligible for compensation
clarify what losses you can claim for
working through the compensation claim forms with you
supporting you through the compensation claim process

This is a free service that is supported by MPI, run independently by DairyNZ and Beef + Lamb NZ.

Call us on 0800 322 281 and we will put you in touch with a compensation assistant to help step you through the process and ensure you have the answers you need. Alternatively you can email the team at dbcat@dairynz.co.nz or dbcat@beeflambnz.com.

To help you with your compensation claim check out the M. bovis Compensation Guide.