Farmers will soon know if they're going to have to cull tens of thousands of cows in a last-ditch attempt to end the Mycoplasma bovis outbreak.
Minister of Agriculture Damien O'Connor will meet with industry leaders on Tuesday to go over the evidence and come up with a plan.
But with winter approaching, there are fears the disease will be spread to so-far uninfected farms when herds get moved to greener pastures. That process usually begins on June 1, which farmers call 'Gypsy Day'.
"The migration has to go ahead," Mr O'Connor told The AM Show on Monday.
"Grass has stopped growing in the South Island, they need to move them where they can get feed over the winter. It's a big, big call to say 'stop, no movement'.
"But farmers have to double-check that firstly they're not moving infected animals... and that the farm you're going onto is not infected or one of interest. It's up to the farmers to check those things for themselves."
- Hope of rapidly eradicating Mycoplasma bovis 'almost gone'
- Cow black market putting industry at risk of Mycoplasma bovis
The problem is M bovis can be carried by cows that otherwise appear healthy. It's difficult to know whether a cow has the bacteria just by looking at it.
Federated Farmers president Katie Milne told The AM Show it could be November before it's clear how far the disease has spread, thanks to the winter migration.
"Animals that seem to be perfectly healthy have got this disease in amongst them. If it blows out when they come to springtime and they have cows that don't come into milk, calves that get sick... that's a hell of a lot to deal with when you're already under a lot of pressure with cows calving and all those things."
If the decision is made to cull entire herds, Ms Milne says farmers will be heartbroken.
"People with healthy cows and having to cull them is absolutely abhorrent to them... A lot of them have said, 'I would rather try and farm through this. Give me the tools, train me to look for it, have good diagnostics there so we can isolate animals immediately when they look sick, and deal with them by culling individuals.'"
Mr O'Connor says about 38 farms have so far been infected, but expects that to rise to about 70 after the migration. He says an expert panel last week was split 6-4 on whether the disease could be eradicated or not.
"If we think we can eradicate, then clearly the best thing is to go through and cull those herds in their entirety."
Slow to compensate?
In the meantime, the Government says it is putting "millions" into supplying farmers that can't migrate with feed for their herds.
But Ms Milne says compensation has been slow to come, and putting many farmers' businesses at risk because the process often takes too long - they're used to a 14-day turnaround on sale to payment, not several months.
"Once the stock are gone, there's no milk income... the process has taken way too long for those farmers who are in that situation. They're really, really struggling. Banks have supported them until now, but their backs are against the wall and their businesses are very close to folding in some cases because of the slowness of the compensation."
National Party leader Simon Bridges says there is a "lack of certainty" for farmers he hopes is cleared up after Tuesday's meeting.
"Let's not try and play politics on this. We're here to help if we can," he told The AM Show.
"Obviously we have had strong backing from farmers over the years, so we want to be supportive of them, and I think that's about supporting the Government to get on with it, provide certainty, go a good job."
Mr O'Connor admitted in some cases compensation has been slow to come, but not all, and delays were usually around to inaccurate information being supplied.
Last week's Budget allocated $85 million towards fighting M bovis. National's agriculture spokesman Nathan Guy has acknowledged farmers will have to bear some of the costs involved, and Mr Bridges said that is likely to come in the form of a levy, which he disagrees with.
"I reckon more costs on the farmers isn't fair."