When to one or more of the above conditions there are added overfeeding or what is worse a low condition from starvation or unwholesome food (permeated by bacteria or cryptogams or containing vegetable acids), and when to crown all there are frequent exposures to cold or wet, we have a vicious combination especially conducive to kidney trouble. Habitual retention of urine in mares in harness, in house dogs, or in horses in railway cars, and violent exertion, or sprains of the back are among the remaining accessory causes. _Symptoms._ These are often slight or obscure, so that not only owners and attendants but even veterinarians are liable to overlook them. Loss of flesh, flabbiness of the muscles and a lack of spirit and energy are among the first symptoms. The _horse_ appears stiff, especially in his loins and hind limbs, and fails to advance the hind feet as far under the belly as formerly, and straddles more. When put to work he is early fatigued and appears unfit for sustained exertion. His movements are slow and if urged to a trot he may even groan with every step and quickly settles back to his sluggish pace. If turned sharply round on himself he does so with difficulty and often groans. When he is mounted or when the loins are pinched he may droop to excess. If you come on him lying down, and urge him to rise he may rise on his fore limbs and sit on his haunches until urged before he makes any attempt to raise himself on his hind. The _dog_ may spend most of his time in the kennel, and show little disposition to run, play or hunt. On the contrary the owner may have to call him several times before he will come out and then he moves listlessly, wearily and even weakly. In all animals the appetite is poor or capricious, and the patient gradually loses condition, at first slowly and later, after a few weeks or months, more rapidly. The advance of anæmia is also steadily progressive. Dropsical effusion is not uncommon. It is often prominent in the horse as stocked limbs, but may be absent for a length of time. In other animals it is more likely to appear later in the disease and under the chest or abdomen or in one of the internal serous cavities. Trasbot has found it absent for months in the nephritic dog. The exploration of the kidney through the flaccid abdominal walls in small animals, and through the rectum in small horses and cattle, may reveal renal tenderness and even swelling. If there is a tendency to frequent passage of urine in small quantities, or to straining without micturition, the indication is of value. There may be little or no fever, and, when left at rest, little evidence of discomfort.