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Why is my dog's poop dark or black after switching dog food?

Updated On September 23rd, 2025

Pet's info: Dog | Golden Retriever | 3 years and 6 months old

My dogs poop has been a lot darker lately, almost black. It's healthy texture. She did start eating Purina dog chow this week (she's eaten Pedigree her whole life), otherwise as far as I know she didn't get into anything weird. It isn't consistent either, I found some dark ones in the yard early this week, but yesterday she was pooping normal. Today dark. Is this reason for concern? I can sometimes be a little too vigilant about her poop cause she rarely shows she's sick but dont want to ignore

4 Answers

Most Helpful Answer

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Answered By Dr. Leigh, DVM

Veterinarian

Published on November 1st, 2016

More than likely it is from the change in food but black, tarry stool can be a sign of gastrointestinal bleeding. You could take a sample to your vet, when you notice that it is black, and have it tested for blood. That way you will know if it is anything to worry about or just normal color change.

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Other Answers

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    Answered By Andrea M. Brodie, DVM

    Veterinarian

    Published on

    Dark well-formed stools that are not tarry are quite normal and the color is likely due to the new feed. As long as the stool is not liquid, tarry, or light clay colored it is likely normal. When in doubt you can bring a fresh poop sample in a plastic bag to your vet office and have the techs have a quick look at it.

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    Answered By Jessica Desrosiers

    Veterinary Technician

    Published on February 19th, 2021

    Hi there! That is a dark stool. If you're in the process of switching foods, it could be that the switch is happening too quickly and causing GI irritation which is causing both the grass eating and change in stool consistency. Gradually switching over a slower period of 7-9 days, or adding in a probiotic such as plain yogurt (not low-fat or low-sugar) can help. Sometimes, dark or tarry stool can also indicate an issue such as an upper GI bleed (the stool darkens as the blood goes through the digestive tract and is digested partially). If Sabrina continues to have dark stools, shows signs of GI pain or abdominal pain, the stools become mucusy or tarry, or don't improve, a vet visit is best to rule out more serious GI issues.

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    Answered By Dr. Melanie, BVSc MS

    Veterinarian

    Published on April 30th, 2017

    No, this isn't normal. The dark color of the feces can indicate bleeding in the upper GI tract, and that can be caused by a sudden change in diet. I would have him seen by a vet because there can be a medical cause as well for the black poop, such as a foreign body, toxin ingestion, or GI tumors. He should have a health check and the vet can prescribe medications if needed.

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