URINARY CALCULI. 
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existing in a thirty-seven days old calf—atresia ani; hernia, as large as 
a child’s head, in the linea alba, between the navel and os pubis; a 
fissure 2 inches long, in the umbilical region, through which both the 
open meatus urinarius and the urachus opened; faeces were discharged 
by the latter; a canal, the size of a goose-quill, existing between the 
occluded rectum and the bladder, whence the material made its way into 
the urachus. The latter also received the ends of the ureters and sper¬ 
matic ducts. Lancelot saw in calves and goats swelling of the navel, 
which to the touch gave the impression of an umbilical hernia. Several 
animals died because the urine found no exit through the urethra, 
and as the umbilical cord was also closed, the urine accumulated in its 
dilated end below the skin of the umbilicus. Greve found pervious 
urachus in a filly. 
The primary cause of disease is the obstacle to discharge of urine 
through the urethra, and attention should, therefore, first be directed to 
this point. When obstruction can be detected, blistering the parts will 
sometimes close the urachus ; Burmeister succeeded in this way. Should 
it prove impossible to lay open the urethra, the urachus may be further 
divided and the urine thus allowed to escape, a method which does well 
enough in animals intended for early slaughter. Herbet effected healing 
in five days by powdering the parts with burnt alum; March, in the case 
of a calf, by applying a ligature. 
II.—URINARY CALCULI. 
Urinary calculi have only a surgical interest when occurring in the 
urethra or urinary bladder. They result from materials deposited through 
the urine accumulating around hard substances, foreign bodies, clots of 
blood, masses of mucus, &c., which have accidentally found their way 
into the urinary passages; catarrh or inflammation of the urinary 
passages, therefore, often give the first impulse to their formation. 
Calculi are also said to be due to an abnormally high percentage of salts 
in the urine, produced by food and water rich in lime and to a specific 
tendency (lithiasis). Of more importance is the fact that retention and 
decomposition of the urine are liable to cause an alkaline reaction 
and calculous deposit. Such conditions are, therefore, to be provided 
against or removed as soon as possible, and care taken to disinfect 
catheters, &c., before use, and so prevent micro-organisms being carried 
into the bladder. Sometimes deposits occur in the pelvis of the kidney, 
pass into the bladder, there become enlarged, or being discharged 
with the urine remain fixed in the urethra. This explains why the 
symptoms of urethral calculus generally appear suddenly and aie apt to 
recur, and why the stone is almost always found at the nairowest point 
