Diabetes mellitus affects approximately one in 300 dogs, requiring daily insulin injections and dietary management. With good owner commitment and veterinary support, diabetic dogs can maintain excellent quality of life.
Uncontrolled diabetes causes significant welfare harm — hyperglycaemia causes weakness, weight loss, and susceptibility to infection, while diabetic ketoacidosis causes severe systemic illness and death. Well-controlled diabetes, however, allows most dogs to live comfortably for years. Cataracts develop rapidly in diabetic dogs and cause blindness within weeks to months of diagnosis — they cause disorientation and reduce quality of life but can be surgically corrected. The welfare burden of diabetes management falls partly on owners (daily injections, consistent routine, monitoring) and partly on the dog (regular venipuncture for monitoring, dietary restriction). Dogs generally tolerate insulin injections well with appropriate technique. The greatest welfare risk in managed diabetic dogs is hypoglycaemia from insulin overdose — a genuine emergency requiring immediate treatment.