Today we'll be sharing some interesting discoveries pertaining a marvelous organ that is often underestimated, the dog's liver.
For those folks who loved reading stories from Reader's Digest around the mid 80s' may remember the author J.D. Ratcliff who wrote compelling articles featuring organs as if they were talking in first person.
We thought it would be fun to share some interesting discoveries of our dog's bodies in a similar fashion on a weekly basis. So we got our dusty veterinary textbooks out and visited several websites that are posted in the reference section.
So here come some interesting facts about your dog's live, inspired by Ratcliff's style and presented under the "I am Rover's Liver" format.
Let me Introduce Myself!
Hello, it's your dog's liver talking. As an organ, you likely don't know me well as I am tucked deep within your dog's abdomen, right under the ribs, but don't expect me to make my presence much relevant even when I am not doing well. I am notorious for causing vague symptoms that may mimic many other conditions. But first let me introduce myself.
My name is liver, and just from the origin of my name, you can tell a whole lot about me. My name comes from the Old English word "lifer" which most likely refers to life. In German, the liver is called "die Leber" and the word "leben" is a German verb that means "to live."
Even our English word "life" has quite a close resemblance to the Old English word "lifer." Perhaps, that's because I sure play a great role in your dog's life and the life of any living being who hosts me, as I am a vital organ that carries out a wide range of functions which are necessary 24 hours a day.
I Don't Look Great!
I was once considered the largest organ of your dog's body, but now that many physiologists claim that the skin is an organ too. What can I say? The skin has outranked me, but I come right after with a honorable second place.
From an aesthetic standpoint, my appearance is not much candy for your eyes, as you may attest when you chop up liver treats for your dog's training sessions.
I am a basically a brownish/red colored blob with several lobes. The real beauty of me though relies in my "intelligence" in carrying out many complex tasks.
This is not an understatement. According to veterinarian Race Foster, I am capable of performing more than 1,000 different tasks! It would take a whole book to list them all, so I'll try to make it short and sweet for you. My main tasks include metabolizing food, storing items for later use and disposing of stuff that aren't needed or that are potentially toxic. Here's a rundown of them.
I'm a Filtration System
Loads of blood comes in and out of me on a continuous basis. I am technically a sponge saturated with blood, squeeze me and I'll secrete droplets of blood.
Blood is delivered to me via the hepatic artery which supplies me with oxygen-rich blood straight from the heart that keeps me healthy and happy, but the great majority of the blood supplied to me comes from the portal vein which carries particles of digested food straight from the small intestine.
When blood makes it into my filtration system, I sort it into various components: things that are helpful, things that should be disposed of and things that should be stored for later use, yes, just like dogs who bury bones!
I'm a Processing Factory
After your dog eats his chow, I start working on breaking down and processing all the fats, carbohydrates and proteins. For example, I transform carbohydrates into glucose, break down the amino acid building blocks of protein so to separate the nitrogen and help in the digestion of fats by secreting bile.
I basically work extra hard in processing all the good stuff that comes in and transform them into easy-to-assimilate forms that the rest of your dog's body can easily utilize.
When I secrete bile, a substance that aids in your dog's digestion of fats, the bile is stored in the gallbladder and released into your dog's small intestine via the bile duct. Bile also helps wipe out bilirubin, which is the residue of old, broken down red blood cells that need to be discarded.
If you ever wondered why your dog's poop is brown, it's thanks to the presence of bilirubin which is orange/yellow in color. If I get ill, I no longer can effectively get rid of bilirubin which is why dogs suffering from liver disease sometimes get yellow skin (jaundice) and may have gray colored stools.
But wait, there's more. I also make a protein known as albumin, which prevents fluids from the dog's blood vessels from seeping out. When I get ill though, I may fail to produce enough albumin and fluids may start leaking out into tissues causing ascites, which shows up as abdominal distention.
And what about my ability to manufacture blood clotting factors? If you accidentally cut your dog's quick as you clip his nails, it is thanks to me that he doesn't bleed to death.
Should I get sick for some reason though, I might be unable to produce these important clotting factors which can make your dog bleed more easily.
I'm a Garbage Disposal
Along with breaking down those carbs, fats and proteins your dog eats, I also try my best to also metabolize any crap I am exposed to such as harmful substances that are added to processed dog foods nowadays.
I can do this though only up to a certain extent. Remember those pet food recalls from 2005, 2006 that killed hundreds of dogs? The foods in that case were contaminated with aflatoxins and I couldn't always keep up and work hard enough to excrete these. So sadly in such cases, I ended up raising the white flag and failing.
Along with getting rid of harmful substances, I am also responsible for metabolizing medications your dog takes. What I do is try to make them easier to excrete.
Please make sure you follow your vet's dosing instructions to a T and read the accompanying package inserts for symptoms suggesting liver or other problems. If your dog is taking certain drugs that may impair my functionality, your vet may recommend routine blood work just to make sure I am doing OK.
Not all the stuff I dispose of come from bad stuff your dog ingests, some stuff are just part of the body's normal functioning as in the case of proteins. When I process proteins, I end up with urea, a byproduct that is toxic to the body and should be discarded. So I send this urea to the kidneys, where it's filtered from the blood and expelled next time your dog urinates.
And what do I do with the remnants of food after all the goodies have been removed? I simply send them off back into the intestine and out of your dog's body next time he poops.
I'm a Storage Unit
While your dog may not take as many vitamins as you do, I play a role in the metabolism and storage of vitamins. I am responsible for storing several fat soluble vitamins such as vitamins A, D, E, and K.
This is why when a dog goes into liver failure their diet is often supplemented with several vitamins, further explains veterinarian Race Foster. Without these, dogs wouldn't live much longer.
Along with vitamins, I also store metals such as iron, copper, and zinc in the right quantities so they're ready when Rover needs them. My storage unit also houses a nice amount of blood. Consider that I store about 15 percent of the total blood in the body.
Should your dog ever lose a large quantity of blood, all sorts of alarms go off and within seconds I will send off my reserved supply to try to help as much as I can. I also store glycogen in case your dog needs it when his blood glucose gets too low. All I need to do is convert the the stored glycogen into glucose to give your dog a quick energy boost.
I Can Regenerate Myself!
Perhaps this is my most amazing feature. You might have heard about lizards being able to grow back their tails after losing them, well I am proud to say that us livers are also equipped with similar powers.
When we're on the surgery table and the vet finds us injured or affected by disease, we can afford to have even up to three-fourths of us removed, and by the end of the year, we can regenerate and grow back to our original sizes.
Also, I am capable of still performing my duties despite 70 to 80 percent of me being damaged. Pretty amazing, huh? This doesn't mean though that us livers should be taken for granted and neglected! It's important to take good care of us!
As the Canine Liver Disease Foundation explains, my ability to continue to perform my duties despite being damaged by some infection or a massive tumor, is a double edged sword considering that symptoms may show up only once a disease is well advanced, and possibly, non treatable. So prevention is worth a pound of cure.
To keep me healthy and happy make sure to feed your dog a healthy diet, provide access to fresh water, reduce the amount of toxins he's exposed to and keep up with health checks as suggested by your veterinarian.
According to Merck Veterinary Manual possible signs denoting liver problems in dogs include loss of appetite, vomiting, stomach ulcers, diarrhea, seizures, fever, blood clotting problems, jaundice, ascites, increased drinking and urination and weight loss. If your dog is not doing well, play it safe and don't hesitate to have your dog see the vet!
I hope this article has helped you understand me better. You know, I think I am sometimes underestimated and feel a bit in the dark hidden how I am under your dog's rib cage. Take good care of me and I'll likely effectively perform my duties so you can enjoy your four-legged companion for many years to come. Yours dearly,
Disclaimer: The article is not intended to be a substitute for professional veterinarian advice, diagnosis, or treatment. If your dog is sick, please see your vet.
- Merck/Merial Manual for Pet Health, Merck & Co, INC. Whitehouse Station, NJ USA, 2007
- Clinical Anatomy & Physiology for Veterinary Technicians, Thomas Colville DVM, Joanna M. Bassert VMD, Mosby Inc. St Louis, MO, 2002
- Digestive Disease in the Dog and Cat, James W. Simpson & Roderick W. Else, Blackwell Scientific Publications, Oxford, London, 1991
- Pet Education, Race Foster DVM, Anatomy & Function of the Liver in Dogs, retrieved from the World Wide Web on January 4th, 2016
- Canine Liver Foundation, Canine Liver and Anatomy, retrieved from the World Wide Web on January 4th, 2016
- Tufts University, Feeding the Dog with Liver Disease, September 2014 Issue, retrieved from the World Wide Web on January 4th, 2016