Spontaneous animal models for insulin-dependent diabetes (type 1 diabetes).

Insulin dependent (type 1) diabetes in humans is a polygenic, auto-immune disease that is characterized, among other things, by the infiltration of the islets of Langerhans by immune cells (insulite) as well as many serum auto-antibodies (including islet cell antibodies: ICA). The medical goal is to diagnose the condition at a sub-clinical stage and then to prevent the disease from developing. Spontaneous diabetic rodent models, in particular the NOD mouse and BE rat are invaluable to the continuing progress of the work aimed at better understanding the human disease. In addition to these models, the study of type I diabetes in larger animals, having a longer life-span would also be helpful. In dogs and cats, certain minor kinds of diabetes appear to be of type 1. The classification of diabetes types in carnivores remains poorly defined, however; epidemiological, genetic and metabolic studies an required before these diabetes can be used as operational models for the human pathology. Even if the classification of these diseases is clarified, the ethical and social considerations involved with the use of companion animals, will limit the use of these animals as models for spontaneous diabetes. The selection of a specific line of diabetic dogs should perhaps be considered.