CHAPTERV. 



DISEASES OF THE KIDNEYS AND BLADDER. 



Infianunaiion of the Kidneys. Retention of Urine. Incontinence of Urine. 

 Stone or Calculus in the Bladder. Ijtflanmiation 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 sa 

 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 



