200 PEACTICE OF EQUINE MEDICINE. 



The presence of sugar is how ascertained ? 



The urine is generally pale in color, the specific gravity high, 

 and is more or less permanently frothy when shaken. 



Before testing the urine for sugar the albumin should be first 

 separated by rendering the urine very slightly acid with acetic acid, 

 heating, and filtering. 



Give test for sugar, 



1. Take equal volumes of urine and liquor potassas and heat; 

 if sugar be present, a yellow to a brown color is presented, varying 

 according to the amount of sugar. 



The odor of molasses is observed on the addition of nitric acid 

 (Moore's test). This should not be relied on altogether, so that other 

 tests should be made. 



2. Heat to boiling a drachm or two of Fehling's solution in a 

 test-tube; no change should take place. Now add the urine to be 

 tested, drop by drop, and if sugar be present a green color is pre- 

 sented, together with a yellow or red precipitate of cuprous oxide 

 (Fehling's test). 



Other tests may be resorted to, as Trommer's test, Boettger's 

 test, the fermentation test, etc. 



Give a test for the presence of the chlorides in the urine. 



Silver nitrate gives a white precipitate, which becomes dark if 

 exposed to the light. The precipitate is soluble in ammonium 

 hydrate, but insoluble in nitric acid. 



How may pus be detected ? 



If pus be present it can best be detected by the use of the 

 microscope. By the addition of acetic acid the numerous nuclei 

 of the pus-cells are made distinct, so that mistakes ought not to 

 be made. 



In all cases when pus is present in the urine albumin is also 

 present. 



What kind of casts may be found in the urine ? 



Epithelial casts, hyaline casts, granular casts, blood casts, fatty 

 easts. 



