B+LNZ and Wormwise acknowledge the recent death of AgResearch Parasitologist Dr Dave Leathwick and the significant contribution he made to this country’s livestock industry over his lifetime.
After leaving school, Dave got a job with the Ministry for Agriculture and Fisheries which introduced him to science. In 2025, Dave said he was always cut out to be a scientist.
“I was never going to be anything else.”
Early in his career he saw that parasites were becoming immune to the chemicals that farmers had been using for many years and that this would change the way farm systems function.
In 1991 he joined the Parasitology team at Flock House and dedicated the rest of his working life to research that directly benefited New Zealand’s farmers and farming systems, focusing on the long-term sustainability of this country’s pastoral sector.
For Dave, the highlight of his career was working directly with farmers and vets, going onto real farms, dealing directly with real-world issues, and having an impact.
In his trademark self-effacing manner, Dave often said the only thing he had done really well in his career was to build a great team; a team that carried out ground-breaking experiments that no-one else had ever done or had been able to do.
Ginny Dodunski, B+LNZ’s Wormwise Programme manager, says Dave’s work was his life, and although he had black belt in Karate and was a keen hunter and fisherman, he was always aware of the latest parasite science internationally and available to help people with their work, even after his retirement from full-time work last year.
She says he was one of only a handful of agricultural scientists in this country that farmers would contact directly, and farmers appreciated his understanding of the complexity and practicability of farm management as well as his in-depth knowledge of parasites.
“Dave was always so accessible, he was frank, and people knew that what he told them was what they needed to hear – not necessarily what they wanted to hear. He never sugar-coated anything.”
In one project, Dave, along with another parasitologist and a farm advisor, identified farms with multiple drench resistance and worked alongside the farmers to help them apply whathad been identified as best practice parasite management.
The farmers that followed their advice improved their drench resistance status, but the project also reinforced to Dave the importance of ensuring farmers knew that they were being respected as experts about their farms and farm systems and weren’t being dictated to by scientists
For Ginny, Dave’s passing doesn’t just leave a hole – it leaves a chasm.
“If I had to name the one person who was most helpful to me (as Wormwise Programme Manager), it was Dave. In particular, his willingness to contribute to Wormwise’s on-line vet discussion forum and the time he took to put together comprehensive answers to often difficult questions.”
Dave’s expertise in anthelmintic resistance was recognised both nationally and internationally. In 2010 he was awarded the McMeekan Memorial Award recognising his leadership in understanding and managing drench resistance and was named Primary Industries Champion at the Primary Industries New Zealand Awards for his “unwavering commitment to the rural sector.”
Dr Dave Leathwick died on 27 December 2025.
B+LNZ and Wormwise send sincere condolences to Dave’s family, friends, and colleagues.