Van Leeuwen Dairy Group was started by Aad and Wilma van Leeuwen, who arrived in New Zealand in the early 1990s and built a 600ha farm south of Timaru, installing robotic milking machines. Eventually they added a number of satellite dairy and drystock farms. But in May last year the group put nine of its properties on the market to focus on the robotic dairy operation, billed once as the world's largest. KELLY HODEL/STUFF Cambridge farmer Henk Smit details his personal experience of dealing with M. bovis. (First published in April 2019). The van Leeuwens were mentioned in NBR's 2017 Rich List as having an estimated net worth of $60 million.