II5 THB HORSB. 



kidneys. Exposure in cold rain or snow storms, cold draughts of air, 

 and damp beds are liable to further disorder an already overworked or 

 irritable kidney. 



Examination of the "Urine. In some cases the changes of the 

 urine are the only signs of disease that can be detected. Of these 

 changes the following may be looked for : 



Color— White from deposits of salts of lime; brown or red from blood- 

 clots or coloring matter; yellow or orange from bile or blood-pigment; 

 pale from excess of water. In giving medicine remember santonin makes 

 it red; senna and rhubarb, brown; tar and carbolic acid, green. 



Density— The horse's urine may be 1.030 to 1.050, but it may greatly 

 exceed this in diabetes and may sink to 1.007 i^^ diuresis. 



Chemical re-action— as ascertained by blue litmus or red test papers. 

 The horse on vegetable diet has alakline urine turning red test papers 

 blue, while in the sucking-colt and the horse fed on flesh or on his own 

 tissues (in starvation or abstinence during disease) it is acid, turning 

 blue litmus red. 



Organic constituents — as when glairy from albumen coagulable by 

 strong nitric acid and boiling, when charged with microscopic casts of 

 the uriniferous tubes, with the eggs or bodies of worms, with sugar, 

 blood, or bile. 



In its salts — which may crystalize out spontaneously, or on boiling, 

 or on the addition of chemical re-agents. 



Sacctiarine Diabetes or Glycosuria. This disease is also called 

 Diabetes Mellitus and Inosuria. This is primarily a disease of the nerv- 

 ous system or liver rather than of the kidneys, but since the most prom- 

 inent symptom is the sweet urine it may be treated under this head. Its 

 CAUSES are varied, but are chiefly disorder of the liver and disorder of the 

 brain. One of the most prominent functions of the liver is the formation 

 of glycogen, a principle allied to grape-sugar, and the passing of it 

 into the blood for further oxidation. This is a constant function of 

 the liver, but in health the resulting sugar is chemically destroyed in the 

 circulation and does not appear in the urine. On the contrary, when 

 the supply of oxygen is defective, as in certain cases of the lungs, the 

 whole of the sugar does not undergo combustion and the excess is given 

 off by the kidneys. Also in certain forms of enlarged liver the amount 

 of sugar produced is more than can be disposed off in the natural way, 

 and it appears in the urine. A temporary sweetness of the urine often 

 occurs after a hearty meal on starchy food, but this is due altogether to 



