Workmates and others in the veterinary sector say he has made an "enormous contribution" over the last 30 years, as a vet, director and latterly general manager.
"His wisdom, practical farming knowledge and wit are going to be sorely missed," said new general manager and previous business manager Brendan James, who has been with the company since April 2011.
Hilson's career as a veterinarian began in a mixed-practice clinic in late 1989 in North Canterbury, where he quickly found his feet in practice and established relationships in the local farming community and with clients.
An approach from Vet Services co-founder and then-managing director Bert Middleberg during the Christmas holidays of 1990 meant the North Canterbury stint was short and sweet, and Hilson returned north the following year.
He's become renowned for his knowledge of the Hawke's Bay countryside, closely involved with many local farms through an enjoyable and rewarding mixture of vet work, including the provision of animal health plans, advisory work and hands-on trials.
During the three decades he had seen animal health and welfare make tremendous advances, particularly in production stock management, and been involved with numerous ground-breaking research projects, notably the bearing study which contained findings still often referred to today.
As general manager, he led the company with a strong message about community, and had been publicly vocal about his frustration with the lack of understanding and government support shown to farmers, particularly with this year's drought.
In May, a photo of the Waipukurau clinic went viral after staff stripped down to bare all in support for their local community and to encourage those who were struggling to get in touch.
The general manager was pleased with the positive response, and that isolated farmers were happy to open up and reach out to their vets for support.
"It's quite a privileged position in a way," he said. "It's not always easy, you have a few gnarly conversations at times."
Hilson and wife Karen look forward to taking on new challenges on the farm, and hope to help educate young shepherds and vets with a keen interest in deer farming moving into the industry. He will continue to be heavily involved in many community groups and deer farming group Advance Party, along with other industry roles.
Since 1974 Vet Services (HB) Limited has worked alongside the Central Hawkes Bay Farmers Vet Club to deliver a quality veterinary service to its members. It now has a staff of about 150 across its Hawke's Bay-Wairarapa region.