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Why is my pet's poop dark, bloody, or tarry with mucus? Is it serious?

Updated On September 23rd, 2025

Can IBD or cancer cause black tarry stool or reddish brown or reddish brown with blood and mucus? Can both occur, basically dark stools with blood and mucus?

1 Answer

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Answered By Dr. Melanie, BVSc MS

Veterinarian

Published on January 20th, 2018

Yes, both can cause blood in the feces, either from bleeding in the upper GI tract (dark stools) or in the lower GI tract (bright red blood in the feces). It could be possible as well to see bleeding in both the upper and lower GI tract. Blood in the stools can have very serious causes, so if you are seeing bloody stools in your pet, I would have them seen by a vet as soon as possible for it. I hope this helps!

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3Pet Parents found this answer helpful

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