Photo: Unsplash
- No further infections yet at the Moeraki farm
- Investigations are underway at a Dunedin farm
- Dunedin farm is not linked to the six farms initially identified as being at risk
The Ministry for Primary Industries is confident it has the resources it needs if the bird flu outbreak becomes more widespread.
On Thursday, MPI said ongoing testing was not showing any signs of disease on other farms operated by Mainland Poultry.
The H7N6 strain was found at its Moeraki farm, where two of four sheds had the high pathogenic strain of avian influenza.
Samples from a smaller free-range poultry farm near Dunedin, that is not owned by Mainland Poultry, are expected on Thursday or Friday and the farm remains under restrictions.
About 1000 samples have been received for testing at the laboratory at Wallaceville, Upper Hutt.
But as the wait goes on to see if a second farm has the virus, one conservation biologist said the logistics of free-range farms means they present a huge risk.
Auckland University conservation biologist Dianne Brunton said she will not be surprised if the infection is found there.
"I mean, it's incredibly contagious and without knowing the details of of the farming practice you know about who moves where, how eggs are collected and moved around without knowing all of that, you can't say they're not connected at this stage."
Brunton said it could even spread further.
Mainland Poultry's infected Hillgrove Egg Farm. Photo: Supplied / Otago Daily Times
"I wouldn't be surprised at all if it does get detected at a number of other farms in the region, you know, knowing those connections and those connections can be very, very small connections because it's so highly contagious.
"So knowing those connections will be kind of the answer to figuring out how this thing is moving around."
Laying hens foraging outside are thought to have been infected with the H7N6 strain at an Otago farm through a low pathogenic virus from wild waterfowl.
But Brunton said while wild birds can carry the low pathogenic form, free-range poultry farms with large numbers of birds can act like an incubator.
"Free-ranging is great because that takes care of the welfare of the birds, but you're still concentrating tens of thousands of birds together in quite an unnatural way.
"And those birds all have fairly low genetic diversity, they are all the same kind of birds, all the same breeds, so that's a perfect incubator," Brunton said.
Chicken carcasses from Otago farm taken to landfill
Culling of the 80,000 birds from the Moeraki site continued on Thursday, using CO2 containerised gas.
Mainland Poultry chief executive John McKay said the carcasses, among other things, were being moved to a secure landfill.
"We're also disposing of all the material on site, so the manure, the leisure, the eggs, the PPE equipment that we have there.
"All of that material is is being moved and via secure trucks to a high security landfill in Southland, so that work is continuing as well," McKay said.
MPI director-general Ray Smith. Photo: RNZ / Samuel Rillstone
MPI director-general Ray Smith appeared before select committee on Thursday, confident MPI had the resources if bird flu becomes more widespread.
"What I'm pleased about is the way we've got ourselves organised, we've been able to activate all of our people and we are we're managing the workload as we need to at the moment.
"You know, if this thing spreads to a whole range of farms all at once to become infected, it will start to create a different sort of mode."
Smith said compensation for impacted farmers is currently being figured out.
Testing will continue for the next few weeks as the incubation period for the disease can be up to 21 days.
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