My male hamster is bleeding from the bottom, with visible blood at the anus

First, a bleeding bottom may be caused by internal ‘heat’ from eating too many high-calorie snacks such as peanuts, sunflower seeds, and nuts, which can lead to anal bleeding. It is recommended to stop such foods and give more water to help metabolism.

Second, it could be from cage fighting or injury; rule out fights with cage mates and check for sharp objects in the cage, removing any that could cause puncture wounds. The owner can first disinfect with iodine, press with a cotton swab to stop bleeding, and see a vet if possible.

Third, it may be caused by intestinal bleeding, such as prolapse from chronic diarrhea; in that case, promptly take the hamster to a clinic for examination and treatment.