The Ministry for Primary Industries confirmed yesterday that more than 22,000 cattle at properties infected with Mycoplasma bovis will be culled.

Director for Readiness and Response at MPI Geoff Gwyn spoke to The Muster's Andy Thompson about the reasoning behind the cull.

"It's based off some 113,000 tests that we've completed over the last eight months...we think we understand where it is and where it isn't and that's the important question if you're going to depopulate."

There are 28 infected properties and Gwyn confirms that all will be compensated.


"Any act we carry out under the Biosecurity Act that leads to a verifiable loss for the farmer is a compensatable [sic] activity."

Gwyn says that there is the possibility that more properties may be affected by Mycoplasma bovis but the cattle disease is not endemic throughout New Zealand.

"In context it's actually quite a small network, though 28 does sound like a big number to the layperson."

Gwyn says there are continuing investigations into how M. bovis got to New Zealand and from which country.

"It's very rare you find a smoking gun," says Gwyn but he believes the index farm is in the Winton area.

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