What does it mean when a dog passes wine-red, paste-like stool?

According to the photo, the dog is passing bloody, paste-like stool, which may be caused by hemorrhagic enteritis. Because the dog’s energy is good, parvovirus infection can generally be ruled out. Hemorrhagic enteritis may be caused by irritating food, viral infection, bacterial infection, or parasites. It is recommended to take the dog to a veterinary hospital promptly to prevent the condition from worsening. The vet will perform appropriate tests based on the situation and apply suitable treatment according to the results.