The canine urogenital regulates body fluid. Substances produced during metabolism, or substances which can even be harmful to the body, are excreted via the production and expulsion of urine. The urogenital system consists of kidneys, the urethra, and the urinary bladder. Kidneys Dogs have two kidneys. They are connected to the bladder via the urethra, and are located near the lumbar section of the vertebral column. A kidney can be divided into a cortex (outer layer) and a renal pelvis, and an additional adrenal gland, which produces hormones. The most important task of the kidneys is to clear metabolites from the bloodstream. This is achieved through a complex process in which urine is filtered from the blood, collected inside the renal pelvis and transported via the urethra into the bladder. The amount of water excreted changes depending on the amount available. If no sufficient amounts of water are consumed, urine is concentrated in order to limit any further loss of fluid. The kidneys also produce a hormone that stimulates the production of red blood cells. This mechanism helps to correct a drop in blood pressure. Urinary bladder and the urethra The urinary bladder collects urine. A sphincter muscle allows the dog to open the bladder and excrete urine through the urethra. In female dogs the urethra is much shorter than in male dogs. This makes it easier for bacteria to ascend into the bladder. For that reason, inflammation of the bladder is more commonly seen in female dogs. Urine Canine urine is normally bright yellow and has strong smell. An important compound of urine is urea, which is synthesized in the liver, and allows the body to discard ammonia - a waste product of protein metabolism. Small amounts of sugar and salt may also be found in urine. When the amount of water excreted increases, the urine becomes lighter in color. On the other hand, if more water is reabsorbed, the urine becomes a more intense yellow. In case of injury or trauma, an involuntary loss of urine into the abdomen may occur. If this happens, these ammonia metabolites can severely affect the central nervous system, and cause internal poisoning.