Don't forget to deworm your dogs every three months. I just recently dewormed my dogs because of intestinal worms. One of them exhibited symptoms on worm presence and the other had poop with blood.
Some bloody discharges can be caused by intestinal parasites. Other times it can be due to the parvo virus or cancers or tumors. What's important is, before your dog ends up with intussusception, we should try to prevent the causes that we can control... this includes deworming them regularly and annual vaccinations.
Viral caused enteritis such as parvo or distemper can make a dog's intestines "telescope". This is often caused by one part of the intestine moving faster or slower than the other. Although this often resolves itself, others require surgery. I hope this short bit of information has helped.
