"He just reached up on the kitchen counter, grabbed the wash rag, and sucked that thing down like a Hoover!" said the owner of a big basset hound named Hugo, who was brought to the clinic.

Science will probably never be able to fathom why animals, especially dogs, occasionally eat objects that are not food. When a foreign object causes blockage of the intestine, however, it can be a life-threatening medical emergency. Dogs are more likely than cats to swallow foreign objects, and they are not always very selective. Things that a dog might decide to swallow range from plastic action figures to batteries to wash rags. Cats usually prefer things like string, tinsel, and Easter grass.

The most common symptom of a blockage caused by a foreign object is vomiting. Dr. Sheila McCullough, a veterinarian at the University of Illinois Veterinary Teaching Hospital in Urbana, says, "Instead of vomiting once or twice, the animal may vomit ten times in a day. If the animal vomits every time it drinks water, this may indicate an intestinal blockage." Dr. McCullough warns, "Unfortunately, the problem may not be that straightforward. Sometimes the object causes only a partial blockage, which means that some food and water will continue to move through the system." The object may also move but get stuck periodically, which means that the signs may not be consistent and vomiting may not occur every time the animal eats or drinks.

The object could be in the animal's intestine for a long time before it is discovered. Dr. McCullough says, "In my experience, the longest amount of time that an animal had a foreign object in its digestive system was 3 months!" The main way to diagnose an obstruction is by taking radiographs (X-rays) of the animal's abdomen.

The most important thing a pet owner can do to prevent this problem is to make sure that things that could be swallowed are kept out of reach of pets. Dr. McCullough says, "People go to great lengths to "child-proof" their homes. It would save people a lot of grief and money if they would 'pet proof" their homes as well." If your pet starts vomiting, look around and think about what is in your house and what the pet could have eaten. Dr. McCullough's rule of thumb is, "If they can get in to it, they will!"