714 CERTAIN ABNORMAL CONDITIONS OF THE URINE. 



charge over a complete period of twenty-four hours are not 

 perceptibly augmented. 



The greater number of such cases of hydruria in the horse are 

 intimately associated with disturbed digestion and assimilation, 

 with perverted gastric and intestinal function, and more rarely 

 with skin disease ; they are attended with great thirst and 

 ingestion of large quantities of liquids. The occurrence of 

 dyspepsia of this form, complicated with increase of the urinary 

 secretion, may in a great proportion of cases be traced to im- 

 proper food or contaminated drinking-water. Fodder of any 

 kind which has been damaged by exposure to excess of 

 moisture, or otherwise deteriorated by the development in it of 

 certain ves^etable orgfanisms, or oats which have, by certain 

 chemical processes, been somcAvhat bleached or whitened, are 

 very fruitful causes of this unnatural condition of the urine. 



h. Deficiency of Water is, when occurring, probably not 

 associated with increase of solids as a whole, or in excess over a 

 definite period, but usually with a distinct increase of these in 

 a given amount of the liquid ; we observe this condition in horses 

 doing rapid and severe work, entailing considerable cutaneous 

 transpiration, and the consumption of much nitrogenized 

 food. Such cases are usually marked by an increase of urea. 

 When the quantity of urine secreted is much diminished, with- 

 out an obvious means of accounting for the decrease either of 

 water or solid matters, there is reason to fear impairment of 

 secretory power from elementary disease of the kidneys. 



c. Excess of Urea. — This, the complex, highly nitrogenized 

 material of urine, believed to be largely dependent for its 

 existence on the changes or disintegration of nitrogenous 



o o o 



tissues, and regarded as the medium or combination by which 

 they are removed from the animal body, appears also to be 

 largely influenced as respects the amount present in the urine 

 by the character of the food taken into the body, and the 

 relative amount of other activities taking place. It seems 

 probable that, although part is formed in the blood, a larger 

 amount is the result of changes taking place in the kidneys. 

 With horses enjoying good health, a liberal and rather highly 

 nitrogenized dietary, and in Avliich large quantities of moisture 

 arc thrown oft' by the skin, the urine will be found rich in urea. 

 In diseases of an acute febrile character it has been found in 



