The Urinary System
The urinary system performs several important functions, including the removal of waste products from the blood and the elimination of this waste as urine. The system is comprised of four key components: the kidneys (which produce urine), the ureters, (which transport urine from the kidneys to the bladder), the bladder (where urine is stored), and the urethra, (that carries urine from the bladder to outside the body). Several conditions can affect any of the components of the urinary tract, with a variety of clinical signs depending upon the condition. Common conditions include incontinence, urinary tract infections, bladder stones or crystals in the urine, urinary tract obstructions, chronic kidney disease, renal failure, and cancer.
Symptoms of urinary tract disease are varied: Increased frequency of urination or amount of urine; bloody or cloudy urine; pain during urination; loss of bladder control or soiling in inappropriate places; straining or passing only small amounts of urine; strong odor to urine; or fever, lethargy, or vomiting. If you see any of these signs your dog should be evaluated by your veterinarian.
The resources below will give you a more complete picture of the urinary system in your dog and the diseases associated with it. They offer a starting point for your own research that will be helpful when you talk with your veterinarian.
Overview of the Urinary System - Merck Vet Manual
Lower Urinary Tract Problems - Web MD
Common Urological Ailments - UPenn Vet
UTI Symptoms or Something Worse? - AKC
Getting Pet Health Information Online - AVMA