She was speaking at a public meeting to discuss the response to the outbreak, which will result in about 4000 dairy cattle being culled from five Van Leeuwen Dairy Group properties in the Waimate district.
Van Leeuwen Dairy Group is a high-profile operation founded by Aad and Wilma van Leeuwen and includes the world’s largest robotic dairy barn.
During the question session in Waimate, farmer Mark Adams asked about farming stock "under a roof" in New Zealand, saying the skill set was "open range and sunlight".
He questioned if health protocols would have to be adjusted when moving stock indoors, and if it was something to be mindful of.
On one of the first two farms where the disease was detected, where the animals had been inside for a time, the clinical signs presented were "horrendous", while on a more traditional farm, where the cattle were grazing outside, there were no clinical signs, Ms Barrell, who is a vet, said.
Overseas literature showed intensive farming and high-end technology were often where some of the worst clinical cases of the disease were being seen, she said.
Ms Barrell did point out that the countries where the disease was endemic did have different farming systems.
Bringing cattle under cover did have certain stresses on those animals and required a higher level of management.
The MPI was looking at regulations around that sort of farming activity, which was increasingly being seen in more of the dairy industry, she said.
Beef and Lamb New Zealand farmer-director and Cave farmer Bill Wright had been contacted by two beef farmers in the past two days — one a near neighbour at a property under a "restricted place notice" who was trying to sell cattle, and another trying to sell bulls — but people were refusing to buy cattle out of South Canterbury. He also had 60 bulls cancelled.
It was unfortunate farmers outside the risk area were being penalised financially and he said stock agents were "buying into this nonsense".
"Either they are playing a game or they are misinformed," Mr Wright said.
Ms Barrell said people suffering were not just those being immediately impacted by the disease, but farmers in the community.
"Human nature being what it is, people run for the hills."
