What are the components of the canine urinary system?
The canine urinary system is really very simple. It includes:
• Kidneys: There are two, one on either side of the backbone just underneath the last rib, which gives the kidney some protection. The kidneys remove and collect a range of waste products from the blood, and additionally they are involved in functions like control of blood pressure and secretion of certain hormones. The kidney filters large quantities of fluid every day and concentrates the wastes into urine.
• Ureter: From each kidney the urine passes down a ureter to the bladder. The ureters are muscular tubes.
• Bladder: The bladder is the collection bag for the urine. As the bladder collects more urine the walls stretch. There are two sphincters at the bottom of the bladder that stop urine flowing out, until either a dog decides to eliminate, or the bladder is so full that it empties itself.
• Urethra: The bladder drains to the outside through the urethra. In males the end of the urethra is at the tip of the penis, and in the vulva in females. The prostate gland surrounds the urethra just below the bladder.
Common Canine Urinary Diseases
• Incontinence: This is most often seen in spayed female dogs or aging canines. Stress can also be a factor.
• Urinary tract infections are characterized by an urgency to urinate, pain when urinating, and straining to urinate.
• Bladder cancer: Although not thought to be very common in dogs, it is a possible cause of urinary problems. There may also be blood or mucus present in the urine.
• Canine cystitis: A bacterial infection in the bladder, dogs with canine cystitis may show signs of severe pain and difficulty when urinating. There may be blood or mucus in the urine and the urine may have a strange color and/or consistency and other signs of illness such as fever and loss of appetite.
• Canine bladder stones: Symptoms include frequent uncontrolled urination, straining, smaller amounts of urine, blood in the urine, fever, lack of appetite and lethargy.