342 HEALTH AND DISEASE 



Kreatin (i<peas, flesh). — This substance, which is found in muscle, is 

 a nitrogenous, very weak base, of bitter taste, having the composition 

 expressed by the formula C 4 H 9 N 3 2 + H 2 0. When crystallized from 

 its solution in hot water it forms colourless, oblique, rhombic prisms 

 (fig. 138). Liebig obtained about one ounce of kreatin from 100 lbs. 

 of horse-flesh, and it can easily be obtained from " Liebig's extract of 

 meat". The appearance presented by the crystals is here given. 



Fig. 138.— Kreatin Fig. 139.- 



Kreatinine is a strong base having the same composition as kreatin, 

 less one equivalent of water, and its formula is consequently C 4 H 7 N0 3 . It 

 is constantly present in the urine, and the crystals present the forms here 

 shown. 



Urea Ferment. — Shortly after urine is passed it undergoes decom- 

 position, the urea it contains becoming converted into ammonium car- 

 bonate. This change is associated with the appearance of large numbers of 

 a yeast-like micro-organism named the torula or micrococcus ureae, and is 

 believed to be also due to the presence of an enzyme or ferment in the 

 mucus of the bladder. 



MORBID CONDITION OF THE URINE 



The tissues of the body are constantly wearing away and being reno- 

 vated from the nutritive substances contained in the blood, and the blood 

 is at the same time constantly taking into itself the worn-out materials 

 or waste resulting from the wear and tear of the body, some of the more 

 important of which are discharged through the kidneys in the form of 

 urine. Upon the efficiency, therefore, of the latter organs to free the blood 

 from these impurities will largely depend the health of the animal. 



The normal urine consists of water carrying in solution certain organic 

 and mineral salts. 



In the horse it is a yellowish fluid, having a peculiar odour and an 

 alkaline reaction. Its specific gravity varies more or less according to 

 the nature of the food consumed, work, &c, the average being about 



