For privacy reasons MPI would not comment further on individual cases.
"This includes how and when they may have become infected," the spokesman said.
Hawke's Bay Federated Farmers vice-president and dairy chairman Matt Wade said MPI had informed him that the farm was linked to the original source property of the outbreak (thought to be a farm in North Otago).
"From my point of view, it shows the system is working, finding other properties and drilling down to be able to put a ring-fence around it.
"There will be some concern, especially those farms that are on the boundaries of the property or had animal to animal contact. Those farmers who are surrounding them immediately will be concerned that confidence to sell stock has been effected."
He was confident that 99 percent of the region's farmers were responsible when it came to moving stock.
There would also be a M. bovis information event in Havelock North in the coming weeks to provide farmers and the community with information about the disease.
Another Hastings farming property, with links with the South Island-based Van Leeuwen Dairy Group (VLDG) tested positive in December last year. The disease is no longer considered to be "active" there.
M. bovis is a bacterium that causes illness in cattle, including udder infections (mastitis), abortion, pneumonia and arthritis. It does not infect humans and presents no food safety risk.
It is spread from animal to animal through close contact and bodily fluids, for example, mucus and also milking equipment. Calves can be infected through drinking milk from infected cows.
MPI believes the infection was brought into New Zealand in 2015. A positive test for M. bovis was first noted in 2017 in the South Island.
