PART VI. 

 DISEASES OF METABOLISM. 



CHAPTER I. 

 DISEASES OF METABOLISM. 



DIABETES. 



Definition.— Diabetes is a disease ordinarily characterized 

 by an excessive secretion of urine. It occurs in two forms: 

 (a) Diabetes insipidus; (b) diabetes mellitus. 



Diabetes Insipidus.— Definition. — A chronic disease charac- 

 terized by the passage of a large volume of urine of a low 

 specific gravity and containing no albumin or sugar. There 

 should be a distinction made between diabetes insipidus and 

 polyuria. The latter is a symptom of some other disease. 

 In polyuria, often confused with diabetes insipidus, the 

 volume of urine passed is not constant. The disease is 

 evidently a functional disturbance of the kidneys in which 

 large quantities of water are voided and equal amounts taken 

 into the system. The solid content of the urine is naturally 

 reduced. 



Occurrence.— Diabetes insipidus is not observed very often, 

 but perhaps the larger number of cases is found in dogs. 

 Polyuria is frequently seen in rabbits from improper feeding. 

 Certain foods tend to produce it, which, if continued, may 

 result in a chronic condition resembling diabetes insipidus. 

 There is no doubt but that it is often not diagnosed. 



Etiology. — Several things have been recorded as having to 

 do with the cause of diabetes insipidus: (a) Observed dur- 



