Mycoplasma bovis: battle fatigue is growing but Government claims to be resolute

Last week I was in Wellington speaking to Federated Farmers Dairy Council.    It gave me an opportunity to assess persistent rumours that Government and MPI were losing confidence in relation to the Mycoplasma eradication battle.

I heard both Acting Prime Minister Winston Peters and Agriculture Minister Damien O’Connor say that they were resolute in their determination to eradicate the disease. Whether or not public positions and private concerns coincide could be another matter.

Everything I heard reinforced my concern that there is a gulf between the information MPI is providing Government and the realities of the situation.

Currently, the major battle ground is in the South Island, although that may well change in the future. The Mycoplasma bovis stealth bombers have travelled widely, well embedded in calves.

Farming attitudes also vary according to location. Many of those who are well away from the action are fervent supporters of eradication. But those farmers who are in the thick of it are feeling a mix of fear, anger, frustration, despondency, scepticism and battle fatigue.

The crucial issue remains: how long has Mycoplasma bovis been here?

MPI is still sticking to the notion it arrived around two years ago at the start of 2016 or the end of 2015. Their only apparent evidence for this is theoretical calculations using the genetic clock. I have written of this previously.

In contrast, I am relying much more heavily on information from farmers and other industry people. These people are contacting me to tell what they know. Some are prepared to talk to MPI and have tried to do so, but they feel that their information goes into a black hole. Others are too scared to go near MPI because they don’t trust the compensation system, they are not comfortable dealing with bureaucracies, and they certainly don’t want to raise their heads above the parapet.

For some months I have been trying to alert decision makers to the strong likelihood that Mycoplasma bovis has been here since at least 2014 and the implications of this for the eradication campaign.

As time goes by, I find the evidence continues to build for early arrival by at least early 2014. In recent weeks, I am also getting stronger indications that Mycoplasma bovis was in New Zealand from at least 2008. There is also some intriguing evidence that it may even have been here several years before that – with the initial outbreak possibly being in the North Island. Or perhaps that was a different outbreak.

First looking back just to 2014, there is one farmer who has been saying to me that with hindsight, he now strongly suspects that he had a Mycoplasma outbreak back in both 2014 and 2015. He says that as a graduate in applied science he has been taught to be careful on such matters and not to claim anything without evidence. However, having spent several hours talking to this farmer – who is no longer on this particular property – I am well over 90% sure that he had Mycoplasma bovis.

Unfortunately, the heifers from this property were raised together with the heifers from a considerable number of other properties, before being returned to the parent farms as rising two-year-olds. From there, infection will have fanned out via male calves born in 2016, 2017 and 2018, which were sold for rearing up and down the length of the country.

Another industry person has come to me outlining a situation back in 2008 where there was a major outbreak of uncontrollable mastitis and lameness in a mob of cows that now, with hindsight, has all the distinctive characteristics of Mycoplasma bovis. For reasons which I won’t go into here, there are good records of how these animals were shifted from Canterbury to Otago, where the mastitis and other conditions suddenly flared up, and how the survivors were then sold south into Southland.

This was well before the advent of NAIT, but it is possible to draw a trail of where these animals travelled. It seems there are links through to the Zeestratens, which could mean they were not the original source.

There are other stories that I know, but where disclosing the information publicly would make the farmers identifiable and I do not have permission to do that.

For many months, I have been aware of a historically pervasive health condition in calves in the South Auckland district that goes back the best part of 20 years.  The condition could not be diagnosed at the time as any known disease, so was called ’droopy ear’. The possibility this was Mycoplasma bovis was canvassed but supposedly it could not be correct – after all, we all supposedly knew there was no Mycoplasma bovis in New Zealand. The condition was written up in Proceedings of the New Zealand Veterinary Association in 2013, and several years earlier in a rural lifestyle magazine.

An American-trained vet with considerable experience with Mycoplasma bovis tells me that when he started practising in New Zealand some ten years ago he made a tentative diagnosis of Mycoplasma bovis in some New Zealand animals. However, there was no laboratory here with the expertise to confirm or deny that it was Mycoplasma bovis.

A number of industry leaders have said to me that their support for the eradication program is a consequence of the recommendation of the technical Advisory Group (TAG) who are seen as the experts. However, I don’t believe the TAG ever provided any recommendation. Rather, what they voted on was the more restricted question as to whether or not eradication was technically feasible.

Back in May of this year, and using information available to them as at 10 May, four members of the TAG said that eradication was in their opinion not technically feasible, and six said it was technically feasible.  But the six added various caveats including that they were operating with big information gaps. They also noted that the investigation focus had been on forward tracing rather than also undertaking back tracing.

The TAG emphasised that this was going to be an eight to ten-year war, and that battle fatigue and ongoing resources would be important. Additional caveats were redacted from the report, which was only released last week.

More generally, the messages that I keep getting by phone and email are indicating that MPI is still ‘building the plane while flying it’. And we all know what that means. I am also hearing that the MPI and AsureQuality staff within the system are more than a little stressed by having to travel blind without efficient organisational systems.

It seems that MPI is so busy that it does not have time to adequately check out the alternative infection scenarios and timelines. As such, with almost exclusive focus on forward tracing, and over 3000 farms to trace, everything supposedly still links back to the Zeestratens farms in Southland. But not everyone in MPI is convinced about this ‘company line’.

There are now more than 3000 farms with direct and indirect traces back to the Zeestraten farms. Given these trace farms are where MPI is looking, then that is where they are finding the disease. But even then, some of those links are very tenuous. These links may or may not be how the disease got here, and there lies the nub of the problem.

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About Keith Woodford

Keith Woodford is an independent consultant, based in New Zealand, who works internationally on agri-food systems and rural development projects. He holds honorary positions as Professor of Agri-Food Systems at Lincoln University, New Zealand, and as Senior Research Fellow at the Contemporary China Research Centre at Victoria University, Wellington.
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14 Responses to Mycoplasma bovis: battle fatigue is growing but Government claims to be resolute

  1. Honora Renwick says:

    HI Keith or anyone else who can answer my question:
    “However, there was no laboratory here with the expertise to confirm or deny that it was Mycoplasma bovis.”

    I’m wondering why if that was the case, would samples then be sent overseas? I say this, as a phlebotomist who frequently takes samples of blood that are sent overseas for testing e.g. chromogranin A.

    cheers, Honora

    • Keith Woodford says:

      Honora,
      If authorities had thought it sufficiently important then this could have been done but it was not done.
      KeithW

      • Stephen Averill says:

        hi Keith .Still reading all your articles and thanks for all your information that you are giving the farming community on M Bovis.Can you name the TAG members responsible for this decision to continue with the eradication program.My understanding is that there are at least four members that are against the current decision.Is it not time to start holding these so called farming leaders to account?I have yet to find a farmer in my district that is in favour of the current policy.As per usual the silent majority carry on suffering while the vocal minority get their way.

      • Keith Woodford says:

        Stephen
        The TAG were asked to give their advice as to whether or not eradication of Mycoplasma bovis was feasible.
        Back in May, four members said they thought it was not technically feasible.
        Six members said they thought it was technically feasible but added caveats that they had imperfect information, and that eradication would be dependant on ongoing substantial resourcing, with the program continuing for 8-10 years before victory could be claimed with any certainty.

        The decision to move forward on eradication was not made by the TAG. This decision was the responsibility of the Government after consultation with industry groups and getting endorsement from those groups. They based that decision at least in part on advice from the TAG, but the TAG provided advice around feasibility and did not provide a recommendation as such. The distinction is important.

        It is not clear whether or not the TAG has met since May17. If so, their advice has not been made public. I have heard an MPI official say they have met 5 times (mainly by telephone) but there are only three reports in the public domain
        Keith W

    • Stephen Averill says:

      Dear Keith . Thanks for your reply. As you quite correctly stated, the decision to continue with the M Bovis eradication process was made by the government after consulting with farming industry leaders. It would not have been remotely feasible for the government to continue with the current program without the majority support of the TAG members. The TAG members were a major part of the decision and the individual members need to own and take responsibility for their actions. If these TAG members think they can hide in their rabbit burrows and take no responsibility for their decisions, they are only fooling themselves. Over the last 30 years farming, I am often bewildered how our so called farming leaders who are meant to be representing the farming community, choose to head west while the majority of farmers want to head east. The TAG members I’m sure will be handsomely rewarded for towing the government line. Overseas trips, wonderful overseas hospitality is all part of the job!! The farmers have the absolute right to know who the TAG members are and how they voted on this M Bovis decision. After all, we are supposed to be living in a democracy.
      Thanks Stephen Averill

      • Keith Woodford says:

        Stephen
        The TAG are independent advisers to MPI and the Government. Their names are on the MPI website – the names were made public back in May.
        I disagree with you strongly in regard to your comments about the TAG.
        They have provided their professional expertise, and applied that expertise to the facts as provided by MPI.
        They cautioned as to the quality of some of the information that was provided to them and the challenges of providing good advice given that situation.
        If anyone is hiding behind others, it is the industry. It is the Government that has taken the technical advice from the TAG as to what was feasible and turned that into a policy of eradication, and industry has agreed with that.
        If the policy works, then it is Government and industry who will deserve the credit, but with an acknowledgement to the TAG for their assistance on technical matters. If the policy fails then it will also be the Government and the industry that has to bear any criticisms that might be made. They must not be allowed to hide behind the TAG.

        You may be surprised as to how little the TAG has been paid for their expertise. I I do not know the specific amount, but I know how the system works ,and it is unlikely to be great.

        There are indeed great opportunities for snout in the trough, but I doubt whether the TAG are close to the trough.
        KeithW

  2. malcolm says:

    if you look at animal transfers for every dairy farm infected property i would expect at least 5 non dairy farms

    • Keith Woodford says:

      Malcolm
      Unfortunately, the traces per infected farm can be a great deal more than that. One of the problems is that calves from different properties travel together to saleyards and then beyond – for example across Cook Strait – and then get segregated at the other end of the journey. But NAIT records cannot show this intermingling during transport.
      Most farmers donate a couple of calves per year to the IHC program, or to rugby club or school projects, and all of these calves are intermingled as they work their way to destination farms.
      KeithW

      • malcolm says:

        i know what you are saying i should of said for every dairy farm i would be expecting MPI to have found at least 5 infected non dairy farms i had a trace of an animal that arrived in late 2015 , i pointed out to MPI , it had contact with animals that were live exported to both china and sri lanka

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  4. malcolm says:

    Malcom
    You wrote:
    what i would like to ask you to be as certain as possible with a 100% spring calving herd over 11 weeks

    1. if i got bulk tank milk samples tested by PCR which would give a quicker result than culture testing from 10 days into calving at 4 day interval for 5 periods , then 2 tests at 2 week interval followed up by a couple of monthly tests and if all tests came back negative , would i have a high level of certainty that M Bovis is not present instead of one of tests outside of the calving period

    Answer: Just for background information: The PCR test and the culture test do not always agree. The PCR tests for DNA from specific organism. The culture work up will grow a live organism. Not all DNA comes from live organism- the organism could have been alive, the immune system killed it and residual DNA remains, so PCR would recognize it and culture not. Also, each test has a different sensitivity- A PCR may be able to detect, or not detect with precision, an organism when present in very small concentrations. Now having written all that, the PCR and culture agree a significant percentage of the time, but occasionally there will be disagreement. Some people like things all in black and white- you run a test and either the cow has M. bovis mastitis or she does not. But it is not that simple and the factors that influence sensitivity will often be the most problem. So just to let you know there is some grey area. But by the nature of your question you probably understood a lot of the grey area in the process, but nonetheless I wanted to at least start by making sure the grey area was described.
    My experience in US and knowledge of the literature indicates that if the bulk tank milk is “free” (not detectable) of M. bovis on 3 consecutive samples the herd can be considered with reasonable certainty to be M. bovis clinical mastitis negative. Now the operative word here is clinical mastitis. In our part of the world the producers are concerned with the clinical disease. In NZ you folks are also concerned with the subclinical form of the disease and M. bovis associated bovine diseases, which is not restricted to mastitis. The literature findings would suggest that if a cow is going to develop clinical disease, either new or from an existing subclinical one, it would be most likely occur at calving, and more broadly during the first 60 days postpartum. So if I understand your thought, taking multiple samples during the calving period and then for the first 60, perhaps 100, days post calving is a very good idea. But we do not know much about the subclinical form of mycoplasma mastitis as heretofore it is has not been much of a concern. Our best mastitis control producers are taking bulk tank samples and determining the Mycoplasma sp. content weekly. If they get a positive test on the bulk tank they take samples from cows with recent clinical cases of mastitis. Generally they find the infected cow and most will cull that cow. If those samples come back negative they will continue to look for the high somatic cell count cows and culture the milk of those cows looking for mycoplasma mastitis. They then often will cull those cows. The cost to us of bulk tank test for M. bovis or Mycoplasma sp. runs from $10-$25. To me that is pretty inexpensive relative to the problem that can happen to miss detecting the beginning of a problem. So, I would recommend weekly testing of the bulk tank to monitor mycoplasma mastitis. But again, most of our knowledge of detection is based on ferreting out the cows with clinical mastitis or recent clinical mastitis or highly reactive subclinical mastitis cows. You folks have some concerns about the “quieter”, less clinical cows, subclinical cases.

    You wrote:
    secondly by practicing culling high somatic cell count cows and cows that do not respond to treatment be a tool in itself for eradication of M Bovis

    Answer: I hope the answer above will answer this question. I have also attached a couple of review papers where mycoplasma mastitis is discussed in terms of control and other aspects of the disease.

    I hope I have given you a better basis to understand the problem and have answered your questions satisfactorily. Please let me know what additional information I can provide.
    Larry

    “The greatest obstacle to discovery is not ignorance, but the illusion of knowledge” (Daniel Boorstin)
    Larry Fox, Professor,
    College of Veterinary Medicine, Washington State University
    Pullman, WA 99164-6610
    Phone: 509 335-0786
    FAX: 509 335-0880
    email: Fox@wsu.edu

    Shipping address:
    205 Ott Way
    Pullman, WA 99164-7060

    • Keith Woodford says:

      Malcolm,
      Yes, you have indeed tracked down one of the experts. And as you probably realise, he is part of the Technical Advisory Group (TAG). A key point that he makes is that the international experience is in relation to clinical cases, whereas in NZ we are seeking out the much more common (in our environment) sub clinicals. And bulk milk PCR tests only work for clinicals.
      Over the weekend I was looking at the results of a herd that has gone strongly positive on the ELISA antibody tests but consistently negative on the PCR tests. This is happening again and again in NZ. The somewhat arbitrary judgement in NZ is that ELISA positives of less than about 7% are classed as false positives. More than that and it is classed as Mycoplasma bovis positive. But the cutoff of around 7% is more than a little arbitrary.

      And I do like the quotation Larry uses: “The greatest obstacle to discovery is not ignorance, but the illusion of knowledge” (Daniel Boorstin).
      Keith W

  5. malcolm says:

    I am not an expert , this is my understanding is the PCR test is effective for clinical cases and getting on to M Bovis early to avoid the worse effects of M Bovis
    as larry stated most clinical cases occur from calving to post 60 days
    within a single calving period and during the high risk period the postive tests for antibodies (ELISA) and PCR, the results should be closer
    further you move away from the high risk period the detection of antibodies by ELISA would be greater compared to PCR for clinical from what material i have read the results you descibe are within the ball park latter you go into the lacation for example when they did the bulk testing in feb/march most farmers had culled their high somatic cell count cows and hard to treat cows removing high risk cows for shedding M Bovis i would expect very few herds to go positive for M Bovis using PCR tests

    with M Bovis Maststis it appears in all 4 quaters , and with most dairy farmers practices those cows are put straight onto the truck and ends up as beef burgers

    when you take account of dairy farmers practices and the nature of M Bovis and NZ dairy farming systems my thinking is Most farmers have it already covered to mitigate M Bovis

    also from the reading the ELISA test is not that reliable

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