Collecting Your Pet’s Urine and Fecal Samples


Veterinarians don’t have magic wands or crystal balls. They don’t even have wizard caps! When your pet is sick, doctors often rely on diagnostic tests to know how to proceed with treatment. Often this includes blood and urine tests, and fecal tests if diarrhea is the issue.

Sometimes YOU might be the one who has to collect these samples. Obviously, we leave venipuncture (poking a needle into a vein to collect blood) to the professionals, and you probably wouldn’t want to be the one doing that anyways! Urine or fecal samples are simple to collect at home, however, and you may be asked by your veterinarian to do so if they are unable to collect it at the clinic. Here are a few tips and good things to know when collecting them.

  1. The fresher the better – samples that have sat in a container on the counter for two days don’t have much diagnostic value. Old urine can develop crystals or multiply bacteria, leading to false results. Fresh feces increases the chances of discovering giardia, and old feces can cause parasite eggs to larvate and make them harder to identify. General degradation of cells can also occur.
  2. The cleaner the better – more so for urine. Wringing out urine from a towel that your cat peed on will confuse the diagnostics, “mudding up the waters” so to speak as it will be full of artefacts that shouldn’t be in there. Using a dirty container can also introduce bacteria that may not be otherwise present in the urine.
  3. The quicker the better – the sooner a sample is provided, the sooner the test can be run and treatment started. Often urine tests are included in the blood panels sent to the lab, and can still be included if the urine follows it within 5 business days.

But how DO you collect urine and fecal samples?

Fecal samples

Collecting a fecal sample in cats and dogs is fairly straight forward. When your dog is on a walk and it defecates, simply pick it up in the poop bag as you normally would, and bring it in for testing. If you are unable to bring the sample right away, or your appointment at the vet isn’t for a few hours, place the sample in the fridge. We would advise putting it in a zip lock bag to avoid smell seeping, and maybe a paper bag so others don’t have to look at it next to their food! For cats, simply pick a sample from the litter box. Do your best to collect it soon after the cat has had a bowel movement.

Urine samples

Urine is often collected differently in dogs than in cats. Since cats don’t usually go for walks with us (much less urinate on the ground if they did), it is a bit trickier to collect. Often if your cat has urine in its bladder, it is easiest for the veterinarian to simply stick a needle into the bladder and extract urine. This is called a cystocentesis. It is considered a sterile sample. Sometimes there is not enough urine for the veterinarian to palpate a bladder, or the cat is too overweight to be able to feel one. In this case, often a collection kit is sent home. There are a few ways to collect urine from your cat at home:

  1. Slip a tray under your cat when it squats to urinate. This is a bit tricky, as cats don’t often announce when they are headed to use the litter box. There is also a risk of startling the cat and causing an aversion to the litter box, which we don’t want!
  2. Replace the regular litter with a non-absorbable substance. There are commercial products out there such as Nosorb which are meant for this very thing. Once your cat has urinated, you can suck it up with a syringe provided in the collection kit and transfer it to a clean container. You may need to isolate your cat in a bathroom to ensure it doesn’t urinate anywhere else if it doesn’t appreciate the change in litter.
  3. Isolate your cat overnight in the bathroom with the litter mentioned above. If there is no urine present in the morning, you know there is likely a big enough bladder to poke with a needle at the veterinary office.

Collecting urine from your dog is much easier. Simply take your dog for a walk, and slip a tray under them when they urinate to catch the stream. Doing it on the first walk of the morning is best, as it is the most concentrated sample of the day, and it is your best chance that they will urinate as they haven’t done it all night! Sometimes sterile samples are required, which would be done by cystocentesis at the veterinary clinic.

Just like feces, if you cannot bring the sample in right away, place it in the fridge.

Good luck with your future collections!

Written by Michelle Stoyko, RVT