What causes my Great Dane to bleed from his rear end?

The rectal bleeding may be the result of a number of problems. Probably the most common causes of this are mild constipation leading to hard, irritating stools, colitis and proctitis. Dogs get rectal polyps which can lead to intermittent bleeding. Tumors can occur around the anus or in the colon. Rectal fissures and anal sacculitis can lead to intermittent rectal bleeding. The constipation/colitis problem can sometimes require a bit of a workup and rectal polyps can be pretty frustrating to find without an endoscope. Dogs have rectal bleeding at times for no apparent reason. Most dogs with occasional rectal bleeding do not have serious problems as a result of it and many vets do tend assume that most owners are not interested in spending a lot of money to figure out what the cause is, due to this.

Paintedrain2's answer was/is very informative; however, PLEASE take your dog to the vet!

It may be something benign as explained; it could also be something very serious -- and you won't know until a professional tells you.

I'm *not* trying to sound like an alarmist; but, the bleeding could be caused by many things including tumors, cancer, obstruction (from eating something he shouldn'tve), or other illness.

Again, I'm not trying to tell you the sky is falling; it's just that we take the responsibility when adopting a pet to make sure it has the best life we can provide. Our pets cannot tell us what is wrong -- it is up to us to watch them and care for them and when something is just not right, to have a doctor look at them. I mean, if it turns out to be nothing, you'll have only "wasted" $100 (vet visit and maybe an x-ray) and you'll have gained peace of mind.

Check with your Vet. There are several things that it could be including constipation, but you need to know for sure what it is. You can't get the right answer at a board where people can only go by what you are describing. Even a Vet wouldn't suggest treatment for your dog without seeing the dog first.

Blood from the rear end is not "healthy". To directly answer your question, the cause could be anything from a tumor to constipation to poor diet to something stuck in his colon to a hundred other things. Speak with a vet about this as it is not normal.

clara aka BYB Claire - I have now asked you numerous times to stop stalking me. You are a BYB who couldn't handle being told that. A responsible breeder doesn't have the time to wander around Yahoo Answers stalking people and giving immature answers. Don't you have a pregnant puppy mill dog that you should worrying about, not following me around like some ignorant moron? I realize I'm attractive and that Stalkers Love Me, hence the name, but please. I would never love a BYB. No matter how many wonderful things they said about me.

What are you adding to answers other than a permanent record of your ignorance and cruelness? I know, nothing. Go join a BYB group and harass them. If you don't agree with my judgment of you, go read your Cocker code of ethics and the AKC breeding guidelines. I can guarantee you that they don't say "Your source of breeding information should be Yahoo! Answers."

Worms can also cause this to happen, if he gets a sever infestation. Even one ingested flea can cause him to eventually become severely infested.

Take him into the vet and have a fecal done on him...it's inexpensive and quick to rule out at least one condition!

http://wwwlibertydogtraining.com/

I would have a vet check him out..check his anal glands and also have a fecal test done. It may be nothing more then the passage of hard stool on occassion, but it also could be other issues that are more serious.

SEE THE VET it probablly has to do with his glands

see a VET ASAP, Just in case.

VET VET VET VET VET