The Veterinary Science Unit (VSU) under the Animal Health and Welfare Branch part of the Ontario Ministry of Agriculture, Food and Rural Affairs was founded more than 20 years ago. The VSU consists of four staff members with the ability to bring in additional staff as needed. The VSU investigates issues in both domestic and non-domestic animals, investigations are focused on birds, bison, cattle, companion animals, finfish, horses, honeybees, insects, poultry, small ruminants and swine to name a few. Investigation topics under their mandate include antimicrobial use/resistance, biosecurity, contaminants/hazards, emerging/endemic disease, food safety, foreign animal disease, governance, production-limiting, regulated, vector/vector-borne and zoonotic diseases. Investigations are launched when an issue is identified by a veterinarian, laboratory or regional agency and in specific instances the general public.