Diabetes mellitus in the 13-lined ground squirrel (Citellus tridecemlineatus).

Spontaneous diabetes mellitus was diagnosed in six of 126, 13-lined ground squirrels, Citellus tridecemlineatus. Serum glucose values were significantly higher in the diabetic ground squirrels than in the non-diabetic ground squirrels, while serum insulin values of fasted diabetic squirrels were significantly lower than fasted nondiabetic ground squirrels. In addition, the classic diabetic signs of poly-dipsia, polyuria, glycosuria, ketonuria, polyphasia, and weight loss were present. The proportion of islet tissue to total pancreatic area in diabetic ground squirrels was less than 25% of that in the nondiabetic ground squirrels. Both the number and size of the islets of Langerhans in diabetic ground squirrels were less than those in nondiabetic ground squirrels.