A pitch black stool usually indicates an upper GI bleed. It is digested blood.

That means your dog is bleeding from his stomach or small intestine. It could be any number of things. Bacterial infection, ulcer, foreign object (bone, rock etc.), perforation of intestine and so on.

This is something I would take him to the vet for ASAP. Check his gums and mucous membranes (under his lower eyelid) for pink-color. If they are pale or gray the dog is likely anemic and needs to be seen immediately to stop the bleeding.

My GSD has an upper GI bleed a year ago with pitch black stool. She was borderline severely anemic because of it. It took two courses of different antibiotics to stop the bleeding which was likely due to a bacterial infection/ulceration.

This isn't something to write about on a forum. Call your vet, get a stool sample, and get your dog seen.

 

Just checked his gums and lower eyelid- very healthy bright shade of pink

I called my vet actually and he said that it could be his food, but I wanted to see what other people said here

 

only 3 things i know that will cause this, iron from vitamins , oreo cookies and bleeding. in a puppy i am thinking infection. need to make a trip to vet today and bring stool sample.

 

I agree with Huntergreen. I'm a nurse and when we see black tarry stools we think blood. When it comes from higher in the gi tract it has time to darken and turn from red to black. Iron will also do this and some food. But there's no reason to take a chance. I'd say you're due a trip to the vet.

 

I want to be clear- this isn't tarry, this is just black. So this IS something to be concerned about?

 

TOTW is the old formula for Timberwolf Organics. When my dogs were on TO, their stools were perfectly formed and black. Hope it's the food!

 

Really high protein foods w/a lot of iron can do this sometimes. Additionally, I noted that he's only 6mos. and he's eating TOTW and Orijen. I hope they're the large breed puppy formulas because he's getting way too much calcium if not, especially with the added raw. I have had and heard terrible experiences with the adult TOTW and it's lower quality, synthetic vitamins, especially the high calcium (1.6-2.1%) relating to bone growth problems.

Is it like a blackish-green? I think I've seen what you're talking about when feeding my oldest male exclusively Orijen. I do know what you mean by black and not tarry- they look perfect, just dark, right?

 

I just started feeding our mix the TOTW puppy formula. We think he has a grain allergy and I'm trying this to see if that's the case.

Almost immediately, his stools went from brown to black. Nice and firm, perfectly formed, but much darker than before I began feeding him this food.

I also spoke to my vet and given that this puppy has been in and out of the vet since he showed up, we're confident it's not blood, but rather the food.

 

That's good to hear that all of you have similar experiences. Yes, the stool is perfect, just black. Thanks for the reassurance!