DIABETES INSIPIDUS. 449 



causes much thirst and diuresis, probably containing some 

 ingredient which acts as a stimulant to the kidneys, but it does 

 not induce diabetes so readily as hay that is musty, oats or beans 

 which have been musty or damp, even if kiln-dried, and bran 

 having a peculiar greasy odour, more especially foreign bran. 



Diabetes sometimes occurs as an enzootic disease — not due to 

 any atmospheric influence, but following a bad harvest, and 

 caused by damaged food. All writers agree in condemning kiln- 

 dried oats. I am of opinion that these, if of fair quality when 

 put on the kiln, are not so hurtful as is generally supposed, and 

 that they are much more likely to cause disease if given when 

 damp or musty. 



In a stud of horses where glanders prevails, the slightest error 

 in feeding the apparently healthy animals will often bring on 

 profuse diuresis. In one stud under my care, a supper of warm 

 boiled food was sure to be succeeded by several animals being 

 attacked by inordinate thirst and diuresis. Habitual feeding on 

 boiled food is a very common cause, and although animals so fed 

 may look moderately sleek, and lay on fat, they are incapable of 

 performing the same amount of work as others fed on similar 

 tbod given uncooked. 



Semiology and Fatliologij. — The diagnostic signs are excessive 

 ihirst and profuse urination : in addition to these there is 

 failing of the appetite. Some teachers say the appetite is 

 increased ; I have never known this in the horse, but in the 

 do'jr there is often a cravincr for flesli. The visible mucous 

 membranes are pale or sometimes rusty yellow ; the skin is 

 harsh and the coat unhealthy looking ; the animal is debilitated 

 and rapidly loses flesh. The pulse is often slower than 

 natural, sometimes quicker, and always atonic. The mouth has 

 a sour odour ; the horse prefers unclean food and water, and is 

 fond of licking the walls and manger. The urine is of a very 

 pale colour, sometimes as clear as clean water, and has a specific 

 gravity little higher than distilled water, the specific gravity of 

 which is 100, whilst that of diabetic urine is from 100"2 to 100'3, 

 and that of healthy urine in the horse ranges from lOOSO to 

 lOO'oO. According to Lassaigne, the diabetic urine of the horse 

 contains — water 98"0 ; urea, benzoate of soda, acetate of potash, 

 acetate of lime, chloride of sodium, and free acetic acid, 1-5 ; 

 mucus and sulpliate of lime, 0-5 ; and differs from healthy urine 



2 G 



