My sister's dog is a border collie and was up all night with diarhea( looked like tar) anyone have any thoughts/diognosis?

I'd just observe till morning.  check for fresh blood in its stool next time it comes out

The dog may have worms. I would bring the dog to the vet ASAP.

Is it a puppy? could have gotten it from eating another dogs stool that had worms or a cats stool that had worms.

Definitely not normal and definitely not something that I would take lightly.

Edited to add link : www.luvncare.net/faq.htm#B017

Was there any blood?


Get the Dog to a vet ASAP!

black or dark stool is a sure sign of blood

Quoted: black or dark stool is a sure sign of blood

Yes!

thanks everyone.... i talked to my sister and the blood thing was a surprise to her, let her know of the seriousness of the situation, and as a result she is taking her to the vet tomorrow. thanks again.

Bowel obstruction?

Brothers dog had one, made a hell of a mess.  Vet time.

looks like tar can be dangerous. Does it smell a lot worse than common? 1 thought is it could be parvo, depends on the age though whether or not that's likely or possible. They throw up parvo a lot also and just sit around like they feel really bad.

Another thing is it could be some type of internal bleeding. My german shepherd had that 3 or 4 times in his last year or so, it turns out he had had a bleeding ulcer or something like that, but the last time his system was to weak and I watched him bleed to death throughout the night and into the morning without being able to do anything about it.
At 1st it was the diareha like so, so I gave him anti diareha medicine and "pumkin" which does a lot for diareha, but it didn't stop it, and not to long after it was just running out of him even when he wasn't going, like he was leaking.
Then he could only lay around with it running out of him. The vet wasn't able to advise anything over the phone, only an iv might have done something and there's no emergency vet around here. About 2 hours before I sensed that he was going to pass away from it.
1 of the worst nights and mornings of my life. I layed there and cried all day.
Another of my big dogs had passed away only 4 days before on top of that.


Anyhow, that can be serious. If it gets over it, take it to the vet because there's likely still something wrong longterm that could be life threatening another time.
Not medical advice, but based on experience that would be my guess.