"This whole operation is about managing the disease while keeping our future options open. We want to minimise the risk of further spread of the disease. Moving ahead with de-population of the affected farms will allow them to get back to normal business as soon as it is safe to do so."
There was no need to remove animals from other farms in the Van Leeuwen group that were under restrictions. Testing of animals on those farms continued and should infection be found, they would be subject to the same measures.
In the coming weeks MPI would work closely with the animal industry bodies, the Rural Support Trust and others to support the affected farmers.
DairyNZ, Federated Farmers and Beef+Lamb New Zealand supported MPI's actions, while at the same time recognising it was a difficult time for the farmers involved.
The industry bodies believed the measures are necessary to protect New Zealand cattle farms against this disease, Gwyn said.
New Zealand was one of the few countries in the world where Mycoplasma bovis is not endemic, which is why the industry groups supported such significant measures to keep it that way.
"The coming weeks will present new challenges and will be tough for these affected farmers. MPI will work with those affected to make the process as straight forward as possible. I'd like to particularly thank the owners, sharemilkers and farm workers involved for their ongoing support, recognising this is a very difficult time for them."
"I want to be very clear that this isn't something that's going to start tomorrow. This is a big logistical exercise, it needs to be thoroughly planned and co-ordinated and we will be doing it with the farmers who know their businesses best."
MPI anticipated the first stage of the process - removing the animals - would start after consultation with affected parties. Most of the cattle would be sent for slaughter in accordance with standard practice.
All premises, transportation vehicles and equipment involved in culling would follow a strict decontamination and disinfection protocol to mitigate the risk of spreading the disease.
Once de-population was completed, there would be at least a 60 day stand-down period where no cattle would be permitted on the farms. During this time the infected properties would be cleaned and disinfected.
Following this work, the aim would be to get cattle back on the farms as quickly as possible. Surveillance, monitoring and testing will to remain in place for a period as a further safeguard.
The affected farmers could apply for compensation for verifiable losses relating to MPI exercising legal powers under the Biosecurity Act.
Federated Farmers said destroying the stock was the only logical move.
President Katie Milne said the decision to destroy stock which had been in contact with affected animal was the only option which would ensure peace of mind for the rest of New Zealand's dairy and beef farmers.
"We also support the continuation of strict movement controls on the remaining 13 properties that have been placed under Restricted Place Notices.
"These restrictions have significant implications for the people concerned, and all other farmers, so this action is essential to keep the option of eradication on the table.
"We recognise the disease has come at a significant emotional cost to the affected farming families and their animals. The process of culling whole herds will be very stressful for the people concerned.
"But the disease does not respond to treatment and cannot be vaccinated against. Culling is the only logical option to prevent ongoing suffering of the animals."
From a national perspective, our size, relatively low population and geographic isolation gives us the ability to manage and attempt to eradicate biosecurity incursions, when other countries cannot.
"M. bovis is found in most countries, including Australia, this is a disease that we definitely don't want and we should seek to eradicate it, if feasible.
"We've remained free of many pest animals and pest plants (weeds) and diseases that have decimated other country's livestock industries. For the sake of our livestock industries and the economy, it's crucial we act now to ensure this remains the case," she said.
