Experts split on whether cattle disease Mycoplasma bovis can be eradicated from Kiwi farms

New documents show the Government's advisory panel is split over whether eradication of cow disease Mycoplasma bovis is possible.

The experts have also warned the disease is highly likely to have spread to new farms authorities don't know about.

The Government is trying to eradicate the disease at a cost of nearly $900 million.

However, four members of their advisory panel say eradication is no longer achievable or economically rational.

While the other six members of the panel believe eradication is technically possible, they say there are some red flags.

For example, the movement of animals around the country recently, including on Gypsy Day, is highly likely to spread the disease further.

The expert group is also worried about the effect killing entire herds is having on farmers, concerned the harm that was causing could be outweighing the benefits of eradication.

The Government will reassess whether eradication is still feasible in spring, but for now believes the programme is on track.