The farm is one of four that currently has the disease.
M. bovis eradication programme director Simon Andrew said testing would be stepped up because of the discovery.
"This strain doesn't behave any differently than the strain we have been dealing with, and our existing testing will pick it up, as it has done in this case. It doesn't affect our efforts to eradicate M. bovis from New Zealand."
Andrew said a thorough investigation was under way into historic pathways, which included recorded and unrecorded animal movements dating back to 2018, imported feed and farm machinery, and frozen semen imported prior to the tightening of import health standards for bovine germplasm.
"While considered a very low risk, frozen semen used on the affected property, which had been imported prior to the introduction of the new import health standard, is being looked at.
"Our team is carrying out an investigation on the affected property. At this stage, there is no evidence to suggest that there has been any forward spread on any farms that received cattle from this farm."
The new strain had not been found anywhere else, Andrew said.
"But disease control is all about being cautious, so we will be increasing the summer frequency of our national bulk milk surveillance testing from once a month to every fortnight, as we do over spring."
He said if MPI's investigation into pathways revealed that further action was required, including targeted testing and surveillance on-farm, farmers would be told.
"But at this stage the increased frequency of summer bulk tank milk testing, beef surveillance and tracing animals will serve us well."
Farmers with concerns about the disease can call 0800 00 83 33 or email info@mpi.govt.nz.
Eradicating M. bovis
The Mycoplasma bovis Eradication Programme began in May 2018 and is jointly funded by Government (68 per cent) and DairyNZ and Beef + Lamb New Zealand (32 per cent).
Since M.bovis was discovered in 2017, a total of 276 properties have tested positive for the disease, and nearly 3 million tests have been completed.
In terms of compensation, $231 million has been paid out in 2795 claims.
The cost of the programme, as of June 30, 2022, stands at $588 million, and a total of 178,000 cows have been culled to date.
-Additional reporting NZ Herald
