“And please remember to bring a fecal sample.” Whenever a client schedules a wellness or sick pet visit, our front staff requests they bring a fresh stool sample. We are not fascinated by your pets’ poop, per se, but are concerned about your pets’ well-being and the potential for transmission of parasites to people. That being said, we are routinely amused by the containers in which people bring us their pets’ sample.
So what do we look for in a fecal sample? Mainly parasites, but we also want to see that the color is appropriate, assess if obvious blood is present, and evaluate consistency. What goes in must come out, they saying goes, but lots can happen in-between. Parasites can affect a whole host of organs, blood may indicate tumors or ulcers, color changes may indicate pancreatic or digestion issues, and consistency may be an indicator of allergies or inflammatory bowel disease. Poop is a valuable diagnostic tool.
Many parasites are passed through fecal material. Numerous parasites live within the intestines and colon and lay their eggs within the lumen of the intestines. When the pet defecates, the eggs of the parasites are shed into the environment, waiting for a new host to infect. Most parasites obtain entry into their new host via the fecal-oral route – aka the host eats the eggs in a small quantity of fecal matter. As for dogs this is very common, whether they eat feces off the sidewalk or simply clean their feet after a nice stroll through the park. Roundworms, one of the most common parasites in dogs, can even infect a host by penetrating through the skin of the their feet. Commonly transmitted parasites via the fecal-oral route include round and hookworms and giardia. Less common, but more concerning is toxoplasmosis (a conversation for another day).
Some other parasites take a bit of a more circuitous route, but still need to pass through the intestines of the pet. This includes tapeworms, flukes, and several other parasites. Tapeworm eggs are shed into the stool and ingested by fleas. When the dog or cat eats the flea, the tapeworm is released into the pet, starting the lifecycle over again. Other tapeworms and some flukes require a snail eat the feces, then the pet eats the snail and here we go again.
When you bring a fecal sample and we send it out to the lab, the technicians analyze the sample for the eggs of these parasites. This is performed either by the floatation method where they scan the feces for actual eggs, or via the ELISA method, where the sample is tested for chemical markers to the parasites. It is important to remember that parasites are like chickens: they do not lay eggs every day. Frequently we will ask for several samples from different times – this is especially true for puppies and kittens. We want to maximize our chances of catching any parasitic infections. If an infection is found, appropriate treatment is initiated.
Before the sample is sent out to the lab, it is inspected. Is the color correct? Is there blood present? Is the stool too soft? Is there a large amount of mucus present? If abnormalities are found, we then assess if further testing is needed or if there is a problem with the pet. A particular pancreatic dysfunction results in the stool being a very light cream color. Early in the disease, this is the only clinical sign. If treated dogs usually fully recover. Blood may also be the only sign of a tumor or a parasite. Extremely hard stool may indicate constipation, dehydration, kidney disease, or a lack of fiber. And loose stool may be a sign of a food allergy, parasitism, or an inflammatory process within the intestines.
Simply put, poop can tell us quite a bit about overall health. No one loves playing with a stool sample, so here are a few suggestions to make collection easier. We have stool collection vials that you can take home and then return to us – they have a small spoon and once sealed, contain all the odors. If you collect it in a plastic bag, please double bag the sample. You may also use a jar or other suitable container. We don’t need a large sample, either: about several pennies weight of sample is sufficient. Don’t bring a Great Dane’s worth, please. It is important that the stool be as fresh as possible. If there may be a lag between collection and bringing it to us, you may refrigerate (not freeze) the sample for a day. Don’t neglect bringing samples for cats, either, but do take care to not bring a sample that is old and dried out.
And most important, bring a sample to every annual exam, even if it is in a Tiffany’s box.
Dan Teich, DVM