A fecal floatation for your cherished companion is one of the least expensive tests that I routinely recommend for every dog and cat. It can not only keep your pet safe; but it can also help protect your family as well.
First, animals explore their worlds with their mouths. This is especially true for dogs, but cats do it too. Our pets have a tendency to chew on almost anything with eyesight. And if it tastes good, they might even eat it. This is not limited to toys or things we can disinfect. The outdoor palate of a typical dog or cat commonly includes grass, plants, flowers, twigs, leaves, insects, mice/rats; and our favorite, poop from another animals. All of these items can be sources of parasites and/or bacteria.
Secondly, your pet's poop can look normal, and still be loaded with parasites and/or bacteria. Our cherished companions typically have a much stronger digestive tract than we do, and can tolerate some level of compromise without showing symptoms. This doesn't mean that the invading organisms are not doing damage. It also doesn't mean that your dog or cat isn't passing something on to you. Also, many of the stages of parasites are microscopic, so you can't see them by checking your pet's feces.
Thirdly, routine dewormers and Heartworm preventatives that contain dewormer do not protect against all parasites. There are many pathogens that can cause significant illness to your pets that are not covered by these products. In addition, only a small percentage of pet owners use these products; and most do not give them every 30 days year-round.
I normally recommend that every pet has a fecal floatation submitted 1-2 times annually. If your cherished companion is mostly outdoors, has a tendency to eat/chew on a variety of things from your yard, hunts small varmints, or tends to eat feces from other animals, than I would run this test more often.
I also suggest not to let your dog or cat lick you on the mouth, and do not share eating/drinking utensils with your buddy. Your companion's tongue is his/her toilet paper. Many parasites that affect our pets, can also be harmful to us. Roundworm can cause digestive upset as well as blindness in people. Giardia can cause severe digestive abnormalities. Hookworms can cause skin and digestive issues. Young children, the elderly, and anyone that is immuno-compromised is at more risk for these zoonotic pathogens.
It is best to have a fecal floatation test run by an outside lab because it greatly increases the accuracy of the results. An outside lab will spin down the sample, which increases the chance of finding parasite eggs. An outside lab will use zinc sulfate, a chemical that also increases the chance of finding the parasite stages. Technicians working for laboratories look at a large number of samples routinely, and have more practice at identifying pathogens.
At our clinic, it costs about 17$ to send a fecal floatation to an outside lab. A fresh sample is best. If you can't bring the sample right away, it can be refrigerated for up to 24 hours. 1/2 teaspoon is all that is needed. The results are available within 1-2 business days.