What Are the Causes of Blood in a Puppy's Stool?

There are several causes of blood in a puppy's stool. Blood in the stool may be indicated by an obvious bright red color. Tarry-black soft droppings also indicate the presence of blood in the stool.

  1. Types

    • Bright red blood in a puppy's stool is called hematochezia. The tar-like stools, melena, are black because the blood was partially digested by the puppy.

    Common Causes

    • According to veterinarian Dr. Bari Spielman, the most common causes of blood in a puppy's stool are parasites, such as whipworms, hookworms and roundworms. Bright red blood may also come from constipation if the puppy has been straining to produce hard stool.

    Illnesses

    • Illnesses or infections that can cause bloody stool in puppies include salmonella, parvovirus, colitis or Guardia.

    Considerations

    • Another serious cause of blood in a puppy's stool is by swallowing a foreign object or human medication. The object or drug can damage the puppy's internal organs.

    Warning

    • "The Veterinarian's Guide to Your Dog's Symptoms" (Michael S. Garvey, DVM, et al.; 1999) warns that any puppy or dog that passes only bright red blood and nothing else may have hemorrhagic gastroenteritis, a potentially lethal condition. The puppy needs to see a vet immediately.