The van debuted at the Temuka Saleyards last month.
Of the people checked, 34 per cent were referred to see a doctor, he said.
The aim was to get the van to two or three rural events a month.
The van featured at the National Fencing Field Day at the Otago Taieri A&P Showgrounds and the Charlton Ewe Fair, near Gore, last week.
"The idea is to check as many farmers with gumboots on as we can because a lot of them don't get to see a doctor very often."
The aim was to check about 60 people a day at each event.
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He was finding at the events farmers were pressuring each other to get a check in the van.
"We've had a steady stream here all day," he said at the fencing field day.
He hoped the trend would continue at future events.
The plan was to take the van across New Zealand.
"Come and get yourself checked when you've got the opportunity."