And others furnish the explanation

And others furnish the explanation

Rainey, Ord, and others furnish the explanation. They not only show that a colloid body, like mucus, albumen, pus, or blood, determined the precipitation or the crystalline salts in the solution, but they determined the precipitation in the form of globules, or spheres, capable of developing by further deposits into calculi. Heat intensifies this action of the colloids, and a colloid in a state of decomposition is specially active. The presence, therefore, of developing fungi and bacteria must be looked upon as active factors in causing calculi.

Source: Diseases of the Horse

And not as in itself an efficient one

And not as in itself an efficient one

The saturation of the urine from any or all of these conditions can only be looked on as an auxiliary cause, however, and not as in itself an efficient one, except on the rarest occasions. For a more direct and immediate cause we must look to the organic matter which forms a large proportion of all urinary calculi. This consists of mucus, albumen, pus, hyaline casts of the uriniferous tubes, epithelial cells, blood, etc., mainly agents that belong to the class of colloid or noncrystalline bodies.

Of lime and magnesia taken in the water must be again thrown out

Of lime and magnesia taken in the water must be again thrown out

In the same way the extreme hardness of the water in certain districts must be looked upon as contributing to the concentration of the urine and correspondingly to the production of stone. The carbonates, sulphates, etc., of lime and magnesia taken in the water must be again thrown out, and just in proportion as these add to the solids of the urine they dispose it to precipitate its least soluble constituents. Thus the horse is very subject to calculi on certain limestone soils, as over the calcareous formations of central and western New York, Pennsylvania, and Ohio, in America; of Norfolk, Suffolk, Derbyshire, Shropshire, and Gloucestershire, in England; of Poitou and Landes, in France; and Munich, in Bavaria.

Source: Diseases of the Horse

These are the chief mineral constituents of the urine

These are the chief mineral constituents of the

These are the chief mineral constituents of the urine which form ingredients in the horse's calculi, for though iron and manganese are usually present it is only in minute quantities.

The excess of mineral matter in a specimen of urine unquestionably contributes to the formation of calculi, just as a solution of such matters out of the body is increasingly disposed to throw them down in the form of crystals as it becomes more concentrated and approaches nearer to the condition of saturation. Hence, in considering the causes of calculi we can not ignore the factor of an excessive ration, rich in mineral matters and in carbonaceous matters (the source of carbonates and much of the oxalates), nor can we overlook the concentration of the urine that comes from dry feed and privation of water, or from the existence of fever which causes suspension of the secretion of water. In these cases, at least the usual quantity of solids is thrown off by the kidneys, and as the water is diminished there is danger of its approaching the point of supersaturation, when the dissolved solids must necessarily be thrown down. Hence, calculi are more common in stable horses fed on dry grain and hay, in those denied a sufficiency of water or that have water supplied irregularly, in those subjected to profuse perspiration (as in summer), and in those suffering from a watery diarrhea. On the whole, calculi are most commonly found in winter, because the horses are then on dry feeding, but such dry feeding is even more conducive to them in summer when the condition is aggravated by the abundant loss of water by the skin.

Source: Diseases of the Horse

Which unites with the magnesia derived from the feed

Which unites with the magnesia derived from the feed

Carbonate of magnesia, another almost constant ingredient of the urinary calculi of the horse, is formed the same way as the carbonate of lime from the excess of carbonaceous feed (organic acids) becoming oxidized into carbon dioxid, which unites with the magnesia derived from the feed.

The phosphates of lime and magnesia are not abundant in urinary calculi of the horse, the phosphates being present to excess in the urine in only two conditions (a) when the ration is excessive and especially rich in phosphorus (wheat, bran, beans, peas, vetches, rape cake, oil cake, cottonseed cake); and (b) when, through the morbid, destructive changes in the living tissues, and especially of the bones, a great quantity of phosphorus is given off as a waste product. Under these conditions, however, the phosphates may contribute to the formation of calculi, and this, above all, is liable if the urine is retained in the bladder until it has undergone decomposition and given off ammonia. The ammonia at once unites with the phosphate of magnesia to form a double salt phosphate of ammonia and magnesia which, being insoluble, is at once precipitated. The precipitation of this salt is, however, rare in the urine of the horse, though much more frequent in that of man and sheep.

Source: Diseases of the Horse

Füstenberg and Schmidt have demonstrated on man

Füstenberg and Schmidt have demonstrated on man

Oxalate of lime, like carbonate of lime, is derived from the burning up of the carbonaceous matter of the feed in the system, one important factor being the less perfect oxidation of the carbon. Indeed, Füstenberg and Schmidt have demonstrated on man, horse, ox, and rabbit that under the full play of the breathing (oxidizing) forces oxalic acid, like other organic acids, is resolved into carbonic acid. In keeping with this is the observation of Lehmann, that in all cases in which man suffered from interference with the breathing oxalate of lime appeared in the urine. An excess of oxalate of lime in the urine may, however, claim a different origin. Uric and hippuric acids are found in the urine of carnivora and herbivora, respectively, as the result of the healthy wear (disassimilation) of nitrogenous tissues. If these products are fully oxidized, however, they are thrown out in the form of the more soluble urea rather than as these acids. When uric acid out of the body is treated with peroxid of lead it is resolved into urea, allantoin, and oxalic acid, and Wœhler and Frerrichs found that the administration of uric acid not only increased the excretion of urea but also of oxalic acid. It may therefore be inferred that oxalic acid is not produced from the carbonaceous feed alone but also from the disintegration of the nitrogenous tissues of the body. An important element of its production is, however, the imperfect performance of the breathing functions, and hence it is liable to result from diseases of the chest (heaves, chronic bronchitis, etc.). This is, above all, liable to prove the case if the subject is fed to excess on highly carbonaceous feeds (grass and green feed generally, potatoes, etc.).

Source: Diseases of the Horse

And therefore forms in the passages after secretion

And therefore forms in the passages after secretion

The carbonate of lime, which is present in large quantity in the urine of horses fed on green fodder, is practically insoluble, and therefore forms in the passages after secretion, and its microscopic rounded crystals give the urine of such horses a milky whiteness. It is this material which constitutes the soft, white, pultaceous mass that sometimes fills the bladder to repletion and requires to be washed out. In hay-fed horses carbonates are still abundant, while in those mainly grain-fed they are replaced by hippurates and phosphates the products of the wear of tissues the carbonates being the result of oxidation of the vegetable acids in the feed.

Stricture of The Urethra.

This is a permanent narrowing of the urethra at a given point, the result of previous inflammation, caused by the passage or arrest of a stone, or gravel, by strong astringent injections in the early nonsecreting stage of urethritis, or by contraction of the lining membrane occurring during the healing of ulcers in neglected inflammations of that canal. The trouble is shown by the passage of urine in a fine stream, with straining, pain, and groaning, and by frequent painful erections. It must be remedied by mechanical dilatation, with catheters just large enough to pass with gentle force, to be inserted once a day, and to be used of larger size as the passage will admit them. The catheter should be kept perfectly clean and washed in a borax solution and well oiled before it is introduced.

Source: Diseases of the Horse

Urinary Calculi (Stone, or Gravel).

These consist in some of the solids of the urine that have been precipitated from the urine in the form of crystals, which remain apart as a fine, powdery mass, or magma, or aggregate into calculi, or stones, of varying size. (See Pl. XI.) Their composition is therefore determined in different animals by the salts or other constituents found dissolved in the healthy urine, and by the additional constituents which may be thrown off in solution in the urine in disease. In this connection it is important to observe the following analysis of the horse's urine in health:

Water	918.5
Urea	13.4
Uric acid and urates	.1
Hippuric acid	26.4
Lactic acid and lactates	1.2
Mucus and organic matter	22.0
Sulphates (alkaline)	1.2
Phosphates (lime and soda)	.2
Chlorids (sodium)	1.0
Carbonates (potash, magnesia, lime)	16.0
	1000.0

Source: Diseases of the Horse

If there is reason to suspect the presence of infection

If there is reason to suspect the presence of infection

Treatment in the early stages consists in a dose of physic (aloes 6 drams) and fomentations of warm water to the sheath and penis. If there is reason to suspect the presence of infection, inject the urethra twice daily with borax 1 dram, tepid water 1 quart. When the mucopurulent discharge indicates the supervention of the second stage a more astringent injection may be used (nitrate of silver 20 grains, water 1 quart), and the same may be applied to the surface of the penis and inside the sheath. Balsam of copaiba (1 dram daily) may also be given with advantage after the purulent discharge has appeared.

Every stallion suffering from urethritis should be withheld from service, as should mares with leucorrhea.

Source: Diseases of the Horse

And tenderness of the sheath and penis

And tenderness of the sheath and penis

Symptoms. The symptoms are swelling, heat, and tenderness of the sheath and penis; difficulty, pain, and groaning in passing urine, which is liable to sudden temporary arrests in the course of micturition, and later a whitish, mucopurulent oozing from the papilla on the end of the penis. There is a tendency to erection of the penis, and in cases contracted from a mare the outer surface of that organ will show more or less extensive sores and ulcers. Stallions suffering in this way will refuse to mount or, having mounted, will fail to complete the act of coition. If an entrance is effected, infection of the mare is liable to follow.

Source: Diseases of the Horse