Mass cow cull will eradicate M bovis
Heather Chalmers explores what will be the biggest systematic animal disease slaughter in New Zealand’s agricultural history.
Dairy farmers whose herds will be destroyed as part of a mass cull to control the spread of Mycoplasma bovis are riding a roller-coaster of emotions, says rural support representative Sarah Barr.
‘‘It is great that they have some certainty, but it is obviously tainted with a great deal of loss.’’
About 22,300 cattle from 22 infected farms in Canterbury, Otago and Southland and one North Island farm near Hastings are expected to be culled by June 1 in the biggest systematic animal disease slaughter in New Zealand’s agricultural history.
Barr, a South Canterbury Rural Support Trust representative, said affected farmers were losing not only breeding lines of milking cows, but also younger replacement heifers and calves. The trust was helping to guide farmers through their compensation claims.
She said it was incredibly stressful for any farmer tied up with the M bovis outbreak. ‘‘It’s hard at every level - obviously for those infected farms, but all those under notices of direction, even people who are just trace farms that have been identified for testing.
‘‘Grazing contracts have been cancelled because graziers have felt morally obligated to say that they are being tested. Herd owners have then said, ‘Thanks for being honest, but actually that’s not a risk I’m prepared to take’. I am struggling with that, because hundreds and hundreds of farms have been tested and many go no further.’’
Earlier on there was not a lot of support from the wider farming community for those caught up in the outbreak. ‘‘Some communities are better. I am still finding farmers that feel that they are being marginalised by the primary sector community and it is unfair. These people have done nothing wrong.’’
A big element of complacency exists among farmers, she said. ‘‘Some have realised they have to be smarter in terms of on-farm biosecurity. We all have a responsibility to minimise the risks of this incursion. If it is not M bovis it could be something else in the future.’’
She advised affected farmers to ‘‘assess the risk and take whatever steps and actions you believe are needed to minimise this’’. ‘‘Do it with good information. There are a lot of untruths out there being spread as truth.
‘‘Be informed. Understand what the risk is with animals coming onto your property, whether it is for grazing, or being purchased and traded. Go through a pre-purchase checklist, ask the questions and assess the risk,’’ said Barr.
MPI’s response director Geoff Gwyn said culling was likely to begin on a small scale within the next few weeks. ‘‘We are aiming to have the culling completed by the end of May. We’re hoping to send as many animals to meat processors as possible. Any animals not fit for transport may be disposed of onfarm.
‘‘Once the last animal is removed the property is completely cleaned and disinfected. We will be working closely with each individual farmer to get them back to business as soon as possible.’’
Of an earlier cull of 4000 cows late last year, five of the seven farms were still going through the cleaning and disinfection process, with two starting to repopulate.’’It’s worth noting that once compensated, each farmer will decide how they spend the money, though it’s likely many will repopulate their farms,’’ said Gwyn.
After criticism that compensation payments were too slow after the first cull, MPI said it was likely to make partial payments while it sorted out the fine detail with individual farmers.
PGG Wrightson national dairy livestock manager Paul Edwards said the market should be able to supply sufficient numbers to restock farms without having a significant impact on pricing.’’It is a big number of animals, but I am confident the market will satisfy requirements.’’
While the culling and eventual restocking of farms was logistically a big exercise, it would be spread over months, which would stagger the buying decisions of farmers. Farmers would also be seeking different classes of stock from mature cows to young stock. The slowdown in dairy conversions and flatter export milk returns meant demand for surplus stock was otherwise lower than some previous years. ‘‘If it is staggered over a period of time the effects on price may not be great.’’
While some South Island dairy farmers were deliberately sourcing stock from the North Island, buying and selling of dairy stock was continuing within the South Island, including regions with infected herds, said Edwards.
Gwyn said farmers can expect a tougher stance on on-farm biosecurity and NAIT stock movement compliance in the wake of the M bovis outbreak. ‘‘There remains a big job to do around this disease and there is no quick exit from this situation.’’
Testing of milk from every dairy farm in New Zealand had to date only identified one new infected property. ‘‘This combined with MPI’s extensive surveillance work tracing every possible movement of animals from infected farms gives us the confidence to say the disease is not widespread, but is limited to a network of farms connected by animal movements.’’
M bovis was a bacterium that did not infect humans and presented no food safety risk. It was an animal welfare and productivity issue that can cause a range of serious conditions in cattle including mastitis that don’t respond to treatment as well as pneumonia, arthritis and late-term abortions.
Preventing the spread of M Bovis was everyone’s responsibility – not just those infected farms caught up in the immediate firing line – was the message at a series of combined DairyNZ and Beef + Lamb NZ meetings on managing winter grazing. The meetings, being held throughout Canterbury, were particularly targeted at those managing cattle from multiple sources through the winter period.
While best practice guidelines were being developed, some relatively simple, low-cost precautions can be taken, particularly around keeping cattle from different sources completely separate.
There are a lot of untruths out there being spread as truth. Sarah Barr