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Fecal Testing for Dogs

Learn about fecal tests and intestinal parasites in dogs.

A fecal test, also referred to as a stool sample, is a standard test run on dogs in veterinary clinics.

What Is a Canine Stool Sample?

A stool sample is a tiny piece of your dog's poop that you take into your veterinarian's office to be tested for intestinal parasites. It's an essential task that should be done at least twice a year for most dogs. Some intestinal parasites are contagious to humans, and they're all contagious to other dogs, so it's crucial that all dogs are tested routinely and treated whenever any parasites are found.

How Is a Fecal Test Performed?

Of the many types of intestinal parasites that can infect dogs, only a couple of them can be visible to the naked eye. The rest are too tiny to see, so a fecal test is done to look for parasite eggs present in a stool sample. There are three ways to perform a fecal test:

  • Smear. For this type of fecal test, the veterinarian or a veterinary staff member takes a tiny bit of your dog's poop and smears it across a microscope slide. They then examine the slide under the microscope and look for parasite eggs. This test is routinely done if the results are needed quickly or if there is only a very tiny sample of stool available to test. That can be the case when a dog has diarrhea.
  • Flotation. A fecal flotation or fecal float test is probably the type of analysis used most often to check a stool sample in a veterinary hospital. For this test, a tiny amount of poop is mixed with a particular solution and allowed to sit for a little while with a microscope slide on top. The solution encourages parasite eggs to float to the top of the mixture, where the slide catches them. The slide is then examined under the microscope by the veterinarian or staff to identify parasite eggs.
  • Centrifugation. Sometimes a centrifuge is used to spin the stool sample after it's mixed with the special solution. This can help the parasite eggs float out more effectively so they can be identified on the microscope slide.

Additionally, a special test can be done for Giardia, a protozoa that infects dogs' intestines and is harder to find on a regular fecal flotation test. Giardia tests can be sent to a laboratory to perform, or some veterinarians can do a SNAP test in-house for Giardia.

Which Dogs Should Have Fecal Tests Performed?

Adult dogs should have at least one or two fecal samples tested per year. Also, any time you bring a new dog into your home, he should be checked before being allowed around your other pets.

Puppies are more commonly infected with intestinal parasites then older dogs, so they should be tested regularly until they are at least a year old.

Which Parasites Can Be Found on a Routine Fecal Test?

The following intestinal parasites are most commonly diagnosed through a routine fecal test:

Fecal samples are not 100% accurate. There are not always parasite eggs in every bit of stool passed by your dog, even if he is infected. That means that your dog could have parasites and get a negative fecal result. If your veterinarian highly suspects parasites, even though the sample comes up negative, he or she may wish to deworm your dog anyway. Alternatively, the doctor might request additional stool samples.

A fecal sample that is old is not as likely to show accurate results as a fresh sample that is less than 24 hours old.

It's a good habit to get into to collect a fresh stool sample and take it with you every time your dog has an appointment with the veterinarian. If the doctor doesn't need the sample, he or she can just discard it, but if the sample is needed, it will be ready. You only need to collect a sample about the size of your thumbnail in a clean container.

Remember, dogs don't always show any signs when they're infected with intestinal parasites. You might not see diarrhea, decreased appetite, lethargy, or anything else that indicates there's a parasite load. However, when a dog is infected with intestinal parasites, they can contaminate soil and spread the parasite to other dogs and, in some cases, people, especially children. That's why it's critical that you have your dog's stool tested for parasites routinely, even if you don't notice any health problems.

What If My Dog Is on Full-Time Parasite Prevention Medication?

Your dog should be routinely tested for intestinal parasites even if he is on full-time parasite prevention like that which is included in some heartworm prevention medications. No medication is 100% effective all the time, plus there is no medicine that protects against all intestinal parasites.

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Coccidia in Dogs

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Hookworms in Dogs

Roundworms in Dogs

Dog Worms: Canine Intestinal Parasites

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Bothersome Bugs for Dogs

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