454 SPORADIC DISEASES. 



Post mortem examination reveals the Lloocl dark-coloured, 

 having an ammoniacal smell, and semi-fluid ; congestion of the 

 lungs ; clots of dark blood on both sides of the heart ; the bladder 

 filled with dark or coffee-cololired Urine, and sometimes softening 

 of the liver and kidneys. 



Congestion of the sheaths of the great gluteal nerves has 

 been present in some cases, in which the spinal cord at the 

 lumbar region has been found red, congested, and softened, but 

 in others these appearances have been absent, the spasm and 

 loss of power being due to the effect of the altered blood on the 

 muscular tissue. 



Examination of the urine. — The urine is to be examined as 

 soon as possible after it has been obtained from the animal, 

 as it qiiickly becomes ammoniacal. In every case its specific 

 gravity is much increased — 1*185 or higher. It is highest 

 during the first few hours after attack, as it often becomes 

 lighter in colour, even in those cases which succumb after 

 the first day or two. Boiled, the urine generally gives no 

 reaction, except that ammoniacal gas is emitted. Tested with 

 nitric acid, it occasionally becomes almost solid, but the solidity 

 is rarely due to coagulation of albumen, but to the precipitation 

 of crystals of nitrate of urea in great abundance. These crystals 

 appear as mica-like scales of a brown colour, and fall to the 

 bottom of the glass. At first the addition of the acid causes 

 much effervescence, the urine being strongly alkaline, containing 

 ammonia carbonate. When the effervescence has ceased the 

 urea is rapidly precipitated, and the liquid loses much of its 

 dark colour. Microscopically examined with a quarter-inch 

 objective, it presents the appearances seen in fig. 2G. 



Fig. 2G. — Crystals of Nitrate of Urea. 



In some samples of urine analysed by Ivison Macadam sugar 

 has been detected. 



If the serum of the blood is carefully prepared, the crystals of 

 nitrate of urea can be detected in it by the following process : — 



