CHAPTER V. 
DISEASES OF THE KIDNEYS AND BLADDER. 
Inflammation of the Kidneys. Retention of Urine. Incontinence of Urine. 
Stone or Caiculus in the Bladder. Infiammation of the Bladder. 
THE kidneys are two glands whose chief function it is to eliminate from 
the blood certain substances, the products of the waste of the various parts 
~ of the body. They vary much in weight in different horses, but the right 
one is always more voluminous and heavier than the left, its average weight 
being twenty-seven ounces, while that of the latter’is only twenty-five ounces. 
The diseases of the kidneys and bladder in the horse are not nearly so 
frequent or so varied as in man; but nevertheless they merit careful 
attention, for interference with the functions of these intricate glands is of 
serious moment. 
Before describing the diseases of the kidneys, we may say a few words 
regarding the conformation and structure of these important organs. In the 
horse, sheep, and pig, the kidneys are not composed of distinct lobules as 
they are in the ox; although during development they present a similar 
conformation. If the kidney be carefully examined with the microscope, 
it will be found to consist of a large number of tubes, made up of several 
distinct sections, which differ very much both in situation and in structure. 
. Anyone who has not made a special study of the wonderful conformation of 
these little organs, would hardly credit the wondrous formation, and the 
labyrinthiform intricacy of their secreting conduits, lined with variously 
shaped cells. : 
The little tubes or conduits commence as dilated capsules, composed of 
fibrous tissue, and are lined internally with little flattened plates called 
epithelium cells. Inside the capsule, will be seen a tuft of very small blood 
vessels bound together by tissue, and likewise covered by flattened epithelial 
plates. The tuft of vessels has a main vessel leading to it, and one leading 
from it. The blood brought by the former is freed from water and salts in. 
the capsule, and it returns purified through the latter. 
A is the capsule. B is the tuft of vessels. C and D are the two vessels, 
of which one enters and one leaves the tuft. E is the commencing tube 
lined by cells. The tubes are on an average about one six-hundredth of ‘an 
inch in diameter, and as they pass onwards, they vary greatly in shape, and 
