Acorn toxicity in dogs: rake up acorns ASAP
November 30, 2010 | 04:58 PM
As the leaves fall this time of year so do other parts of the tree, including acorns. Acorns are usually associated with cute little squirrels and chipmunks. However these nuts can be quite dangerous to dogs and other animals (cats don't seem to bother with them).
Acorns contain large amounts of gallotannins. Gallotannins are compounds that belong to a larger class of chemicals called tannins. Tannins are found throughout the plant world and stored in the leaf, seed, root, bud and stem. Small amounts of tannins have a beneficial effect. They are found in many fruits and nuts and act as antioxidants.
Tannins are also commonly found in certain foods, beverages and medications and in smaller concentrations as either coloring, flavoring or a base for other compounds. Plants, like acorns, that contain higher concentrations of tannins exhibit toxic effects.
In the past the biggest concern of acorn toxicity in veterinary medicine was with ruminants (animals that rely on plants and vegetables only for their nutrition) such as horses and cows. Although the bitter taste of acorns usually turns these animals away from acorns certain conditions give them no choice.
When the weather gets very dry and hot, the grass will not grow and these animals are forced to eat acorns in large amounts. The amount of tannins released into their system can lead to a very upset stomach, ulcers, kidney damage and seizures. It has been estimated that if an animal eats enough acorns to be equivalent to 6 percent of body weight toxic effects will occur.
In dogs the worry is not only about an acorn (or part of an acorn) forming an obstruction that requires surgical removal, but also the effects of the tannins. As bitter as the acorns taste some dogs will still munch away. In larger dogs I have seen just a mild upset stomach but in miniature and toy breeds (Maltese, Yorkshire terriers, poodles, Schnauzers, Chihuahuas, etc.) the effects are much more serious. They usually get a hemorrhagic gastroenteritis.
Hemorrhagic gastroenteritis is not really a diagnosis of anything, but rather a description of what is going on. Hemorrhagic gastroenteritis literally describes vomiting and diarrhea with blood in it.
The good news is I have never seen a dog with this condition bleed to death. The bad news is these dogs become rapidly dehydrated, which leads to shock, and lose large amounts of protein into the stomach and bowels that is difficult to replace rapidly.
There is another secondary effect to hemorrhagic gastroenteritis called bacterial translocation. Not only do small numbers of harmful bacteria that inhabit the gut at all times proliferate in numbers, but also the lining of the bowel will also be stripped of its cells. The cells will be replaced in a few days; however, the barrier that only allows nutrients (and not bacteria) to diffuse across the membrane is compromised and allows large numbers of dangerous bacteria into the blood leading to sepsis. This can still be treated but involves much more aggressive therapy and a longer hospital stay (big bucks). Infrequently patients do not respond to even the most aggressive therapy and the condition becomes fatal.
Remember, if you see your dog playing with acorns (especially if your dog is a miniature or toy breed) make sure that you take it away immediately and rake up the rest.
Dr. Kearns has been in practice for 13 years and is pictured with his son Matthew, as well as the newest member of the family, Jasmine, a Labrador retriever.