Diabetes can be classified as either Type 1 (lack of insulin production) or Type II (impaired insulin production along with an inadequate response to the hormone.)
The most common form of the disease in dogs is Type 1, insulin-dependent diabetes, which occurs when the pancreas is incapable of producing or secreting adequate levels of insulin. Dogs who have Type I require insulin therapy to survive. Type II diabetes is found in cats and is a lack of normal response to insulin.
Find out more about pet diabetes here.