150 DISEASES OF CATTLE, SHEEP, GOATS, ETC. 



by alkaline salts and mineral acids, respectively, but their failure 

 as a remedy does not necessarily condemn them as preventives. 

 One dram of caustic potash or of hydrochloric acid may be given 

 daily in the drinking water. In diametrically opposite ways these 

 attack and decompose the less soluble salts and form new ones 

 which are more soluble and therefore little disposed to precipitate 

 in the solid form. Both are beneficial as increasing the secretion of 

 urine. In cases where the diet has been too highly charged with 

 phosphates (wheat bran, etc.), these ailments must be restricted 

 and water allowed ad libitum. Where the crystals passed with 

 the urine are the sharp angular (octahedral) ones of oxalate of 

 lime, then the breathing should be made more active by exercise, 

 and any disease of the lungs subjected to appropriate treatment. 

 If the crystals are triangular prisms of ammonia-magnesium phos- 

 phate or star-like forms with feathery rays, the indications are to 

 withhold the food or water that abounds in magnesia and check the 

 fermentation in the urine by attempts to destroy its bacteria. In the 

 latter direction plenty of pure water, diuretics, and a daily dose of oil 

 of turpentine in milk, or a dose thrice a day of a solution containing 

 one-tenth grain each of biniodide of mercury and iodide of potassium 

 would be indicated. 



In considering the subject of prevention, it must never be for- 

 gotten that any disease of a distant organ which determines the 

 passage from the blood into the urine of albumen or any other 

 colloid (uncrystallizable) body is strongly provocative of calculus, 

 and should, if possible, be corrected. Apart from cases due to geo- 

 logical formation, faulty feeding, and other causes, the grand pre- 

 ventive of calculus is a long summer's pasturage of succulent grasses, 

 or in winter a diet of ensilage or other succulent food. 



The calculi formed in part of silica demand special notice. 

 This agent is secreted in the urine in the form of silicate of potash 

 and is thrown down as insoluble silica when a stronger acid dis- 

 places it by combining with the potash to its exclusion. In cases 

 of siliceous calculi, accordingly, the appropriate chemical preven- 

 tion is caustic potash, which being present in the free state would 

 attract to itself any free acid and leave the silica in its soluble condi- 

 tion as silicate of potash. 



STONE IN THE BLADDER (VESICAL, OR URETHRAL CALCULUS). 



Stone in the bladder may be of any size, but in the ox does not 

 usually exceed half an inch in diameter. There may, however, 

 be a number of small calculi; indeed, they are sometimes so small 

 and numerous as to form a small pulpy magma by which the blad- 

 der is considerably distended. 



Symptoms. The symptoms of stone in the bladder may be 

 absent until one of the masses escapes into the urethra, but when 

 this occurs the escape of urine is prevented, or it is allowed to pass 

 in drops or driblets only, and the effect of such obstruction be- 

 comes manifest. The point of obstruction is not always the same, 

 but it is most frequently at the S-shaped curve of the penis, just 

 above the testicles or scrotum. In cows and heifers the urethra is 



