DIABETES 349 



neither albumin nor sugar. Normal solids are very much 

 reduced in quantity. 



(6) The animal will show intense thirst; large quantities 

 of water are consumed each day, in dogs as much as four to 

 ten liters. Often animals will show a vitiated thirst and 

 will drink contaminated water or even urine. The appetite 

 is usually normal during the first stages, but gradually 

 diminishes and becomes variable. During the later stages 

 the appetite may be lost entirely, the animal becoming 

 emaciated, and various complications develop. The tem- 

 perature remains normal until the very latest stages when 

 it may be subnormal. 



Course. When polyuria results from the food it may 

 disappear in a short time following the change in food. This 

 has been observed particularly in rabbits. In cases of real 

 diabetes insipidus the course is chronic, the disease lasting 

 one or two years. 



Diagnosis. A differential diagnosis must be made between 

 diabetes insipidus, polyuria and diabetes mellitus. Polyuria 

 is distinguished from diabetes insipidus by the symptoms 

 disappearing when the food is changed. The symptoms of 

 polyuria are also more variable. Diabetes mellitus is dis- 

 tinguished by the increased specific gravity of the urine and 

 the sugar content. 



Prognosis. ^Yhile in polyuria the prognosis is usually 

 favorable, in real diabetes insipidus it is bad, the disease 

 terminating fatally after a prolonged course. 



Treatment. An investigation of the food should be made, 

 and if found of poor quality, containing moulds or other 

 objectionable substances, it should be discontinued and other 

 foods substituted. Regulation of the diet is an important 

 factor during the early stages of the disease. Limiting the 

 water supply does not have any appreciable effect on true 

 diabetes insipidus, but if it is a simple polyuria it would be 

 well to restrict the patient to a small amount of water. 



Medical treatment has not been satisfactory. Small doses 

 of valerianate of zinc (0.2 to 0.4) daily, may be tried; or 

 vasoconstrictors used, such as fluidextract of hydrastis, or 

 fluidextract of ergot. Stomachics and general tonics may be 



