Protecting Pets from Internal Parasites
By Dr. Kim Everson, DVM
Just as I was patting myself on the back about my fat yellow Lab’s pronounced weight loss (which I believed to be the result of vigilant calorie control and exercise), I noticed a squiggly white tapeworm meandering over a fresh turd in the yard. Besides feeling disgusted, I was deeply disappointed. While effective, tapeworms are not an approved diet aid!
Intestinal worms are far more common than people would like to think. Regardless of whether you keep cattle, horses, pigs, sheep, dogs, cats and even fish, you also inadvertently keep parasitic worms. As a veterinarian I find myself constantly proselytizing the importance of regular deworming to skeptical clients. To most people “seeing is believing” but on the matter of whether or not your animal has worms, you’ve just got to take it on faith… they most likely do.
Ironically, of all the types of worms that infest dogs, tapeworms are the most likely to be noticed in the stool. Except in extreme cases of parasite load, most kinds of worm live happily in the gut and do not show up in the poop. Microscopic evaluation of a carefully prepared stool sample might reveal the otherwise invisible eggs of worms living in your animal’s intestines, but even this test is not 100% reliable. The maturity, quantity and species of worm present directly affects the odds of finding worm eggs in a given stool sample. It might take multiple tests over several months to definitively diagnose a worm infestation in tough cases.
If I had a nickel for every time a client reassured me their animal doesn’t have worms because the poop looks normal… While parasitic worms can cause weight loss, vomiting and diarrhea, most worm infestations turn up on routine screening of normal-looking poop from outwardly healthy animals. If a parasite is going to be successful, it should not debilitate its host to the point of compromising its own survival! Animals can live quite comfortably with worms in their belly, but over time these parasites take their toll on the health of gastrointestinal system and put humans at risk.
Roundworms and hookworms commonly affect the animals that share our personal space—our pet dogs and cats. These worms infect puppies and kittens before or shortly after birth and are so ubiquitous in the environment that pets are exposed regularly (especially the poop-eating, foot-licking ones). Hookworm larvae hatching in the yard from dog feces can penetrate a human’s bare feet leading to itchy inflamed tracts left as the confused worms (humans are not the proper host) migrate under the skin. Accidental ingestion of roundworm eggs by humans—particularly children who tend to put contaminated soil and dirty hands into their mouths—can lead to infection as well. The Center for Disease Control reports that 13.9% of U.S. residents have antibodies to dog and cat roundworms, indicating a remarkable human exposure to pet parasites. In people, roundworms (like hookworms) become confused and can migrate into the eyes as well as the gastrointestinal tract or nervous system, but most infections go unnoticed just as in the dog or cat host.
We and our animals share the world—for the most part peaceably—with infinite numbers of micro-organisms. Harmful parasites, however, lie in wait for us and our animals in the soil, water and uncooked flesh of our meals. Dining on raw rabbit is undoubtedly how my yellow Lab contracted tapeworms! The best way to avoid becoming host to unwanted parasites is to 1) wash hands after touching animals, their waste and potentially contaminated soil from the garden, sandbox and yard, 2) prepare and cook meat properly, and 3) regularly deworm even asymptomatic animals under the guidance of your veterinarian for maximum safety and efficacy.
Originally printed in farm news column, Fond du Lac Reporter, July 27, 2014