I'll go over both possibilities for you, however he definitely needs to be examined by a veterinarian.

First off, color change can be a result of plant pigments in the diet. If he has been fed any vegetables or fruits within the last 3 days that had red pigment in them, this could be a direct result of that.

As far as health issues go, blood in the urine can be a sign of bladder problems. This can range from being as nonserious as a bladder infection, to the more serious problems such as cancer or bladder stones. The rabbit may not show any other symptoms other than blood in the urine. Bladder stones, bladder crystals, and cancer, are all common diseases in older rabbits. If the rabbit is not neutered, the risk of cancers increase.

If the blood is indeed coming from his stool, this could signal a much more serious problem. Blood in the stool can be an indication of anal cancer, cancer of the glands in the anus, or prostate cancer. Blood in the stool can also be an indication of a serious disruption in your rabbit's gastrointestinal (GI) tract.

My advice is to have your rabbit seen by a veterinarian as soon as possible. They will need to examine him in order to diagnose, or rule out, any possible illness he may have, and determine an appropriate course of treatment.

Hope this helps!

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I am NOT, nor do I claim to be, a Veterinarian.
Always check with your vet for any symptoms your pet exhibits.

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Ahhhhh, then that is MUCH better! Definitely nothing to worry about. You most likely pulled off a tiny piece of skin, which caused the minimal bleeding. The stool sticking to him, once dry, would cause some tugging when trying to remove it. This most likely caused some irritation to the skin, which may have also resulted in the light bleeding. Definitely nothing to worry about.

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I am NOT, nor do I claim to be, a Veterinarian.
Always check with your vet for any symptoms your pet exhibits.

Please press Accept if you find my answer helpful.

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