We tend to not think much about our dog’s bladder other than when dogs need to be taken out to potty or when dogs develop some annoying bladder infection, but those bladders are always working around the clock, and aren’t much acknowledged for the hard work they do. A bladder may just seem like a pretty much boring body part, but turns out it has its own little story to tell us if we are ready to listen. So here are some interesting facts about your dog’s bladder, coming straight from your dog’s bladder mouth!
Hello, it’s your dog’s bladder talking today! Let me tell you a bit about me. I am simply a hollow organ that’s meant to store your dog’s urine coming from the kidneys. For sake of comparison, I am similar to a water balloon. I am pretty much round when I am empty, but will distend and become pear-shaped when I fill up with your dog’s urine. On one end, each of your dog’s kidneys send urine to me through tubes known as ureters, on the other end, urine exits me through the urethra. During the day, I get filled up on a continuous basis and am emptied occasionally.
Did you know? Micturition is the medical term for urination
The beauty of me is that I am “intelligent.” You see, when I stretch beyond a certain “trigger point,” special nerves in my bladder wall will send a message to your dog’s brain, eliciting him to go to the door and bark or ring a bell (if he’s trained to do so of course!) Once your dog is outside, he will look for a spot and relax the sphincter, (a special muscle around the neck of the bladder) so that urine is released.
It’s very important that you pay attention to your dog when he needs to be let out. Sometimes owners leave their house trained dogs home alone for extended periods of time with no opportunity to relieve themselves. You see, the problem is that the kidneys keep sending me urine all the time. This means that as time elapses, I keep getting fuller and fuller and fuller. Your dog can hold it only up to a certain point. If I get too full, more pressure is put on the dog’s sphincter making him more and more uncomfortable. A time may come that your dog may no longer able to hold it so those sphincters relax and urine is released. And if the dog has superb control, and thus, doesn’t have an accident, it’s still not healthy making me store urine for too long. A doggy door or a pet sitter can be a blessing for both me and the dog.
Curious fact: in male dogs, the urethra is longer, allowing them more voluntary control. This undoubtedly plays an important role in a male dog’s marking behavior, explains Dr. Cathy E. Langston, a board-certified veterinarian specializing in internal medicine.
A Word About Puppies
As seen, it is thanks to the dog’s control of the muscular sphincter that urine doesn’t escape from me at the most inappropriate times. Most dogs attain this level of control as they mature. In very young puppies though, as soon as I start to stretch, they are unable to control their muscles of their sphincter so I end up emptying prematurely. By the time the puppy realizes he has to go, a puddle is already made. You can’t blame the poor puppies of course! Their sphincter muscles just haven’t developed yet.
At what age do puppies attain sufficient muscle tone to allow them to control things a bit more? Stanley Coren, in his book “Born to Bark: My Adventures with an Irrepressible and Unforgettable Dog” claims that full control isn’t reached until the puppy is 5 to 6 months. Prior to that though, the good news though is that you’ll see gradual signs of progress. As with human children, most puppies at one time or another will become potty trained. It’s therefore worthless and counterproductive punishing the poor pups for accidents they can’t control! For more on this, read: the physiology behind puppy accidents.
In a healthy, mature dog, with no medical problems, urine flows out of me when the dog wants me to empty with no problem. but even though I am a simple bag-like structure, I can also encounter problems. In most cases, your dog will let you know when something is wrong with me as I will cause changes in his elimination habits that are beyond his control.
However, sometimes things may go unnoticed, especially to busy pet parents. Not always though I am the source of the problem, sometimes neighboring organs may have an impact on my correct functioning. If your dog starts urinating inappropriately out of the blue, consider the possibility of a medical problem.
Urinary incontinence is the involuntary leakage of urine from me. This can happen even when I am not full. In female dogs, the hormone estrogen helps maintain good muscle tone of my sphincters. As spayed dogs age though, these muscles tend to weaken and you may notice a leakage of urine when they’re resting or sleeping, explains Dr. Marie. Fortunately, female dogs with bladder sphincter control problems can be given a medication called PPA (phenylpropanolamine, yeah try to pronounce that!) to help strengthen my sphincters.
Incontinence may be caused by several other problems. Sometimes at birth, puppies are born with defective bodies with ureters that bypass me and open directly into the urethra. These “ectopic ureters” common in Siberian husky puppies will cause incontinence. Dogs with brain or spinal cord disease may dribble urine as nerves can no longer effectively communicate with their brains to send them my message of needing to go. Prostate enlargement in intact male dogs may also cause involuntary leakage of urine. Any medical condition that causes increased drinking such as diabetes, kidney disease and Cushing’s, may cause incontinence and so can certain medications
Sometimes, I may get infected. Female dogs are more predisposed to this because they have a shorter and wider urethra which makes it easier for bacteria to reach me, but male dogs may occasionally get a bladder infection too. When I get infected, the associated inflammation causes me to become overactive causing me to contract more than normal. When this happens, I typically cause frequent urination and the sensation of needing to urinate despite being empty. Blood in the urine is another common symptom.
Sometimes, stones may form. When this happens, I cause symptoms similar to bladder infections. When stones interfere with my urine output, things though may get critical. You see, your dog’s urine contains waste substances that need to be absolutely removed. If they fail to be removed, these waste products can poison cells and cause what’s known as uremic poisoning.
Fortunately, this type of cancer doesn’t affect me at a high rate. According to veterinarian Dr. Deborah W. Knapp, out of all the types of cancer that may affect dogs, bladder cancer comprises approximately 2% of all cancers. The most common type of cancer affecting me is called “invasive transitional cell carcinoma (TCC).” As the cancer enlarges, it interferes with my ability to obtain urine from the kidneys or to excrete urine. On top of that, this cancer may spread to the dog’s lymph nodes and other organs.
Now that you have seen many things that can go wrong with me, here comes some positive news. There are many things you can do to keep me in good health. Here are just a few tips from optimal urinary health from Dr. Karen Becker.
- Keep your dog’s rear end clean. If your dog has long fur in his rear end, keep it well groomed and dry. This can help prevent bacteria from reaching me.
- Let your dog urinate frequently. The longer I store urine, the higher the chances that bacteria will accumulate. By allowing frequent urination, you will help keep me in good health.
- Always provide access to fresh, clean water so all bad bacteria are flushed out routinely.
- Provide a healthy diet and exercise to keep your dog’s body and immune system in good shape.
As seen, I am quite a work of art! Don’t take me for granted. Successful urination is the combined effort of optimal nerve function, mental awareness and the relaxation and contraction of muscles. When any of these components go wrong, you have a problem. I hope you understand me better now! Just don’t forget about me and when you notice a problem with me, see your vet.
Disclaimer: The article is not intended to be a substitute for professional veterinarian advice
- Dr. Mercola, Help Your Pet Experience Optimal Urinary Tract and Bladder Health, retrieved from the web on March 21, 2016
- Clinical Anatomy & Physiology for Veterinary Technicians, Thomas Colville DVM, Joanna M. Bassert VMD, Mosby Inc. St Louis, MO, 2002
- DVM360, Urinary incontinence in dogs, by Cathy E. Langston, DVM, DACVIM, retrieved from the web on March 21, 2016
- Perdue University, Canine Bladder Cancer, by Deborah W. Knapp, DVM, Dipl. ACVIM, retrieved from the web on March 21, 2016
- Born to Bark: My Adventures with an Irrepressible and Unforgettable Dog By Stanley Coren, retrieved from the web on March 21, 2016