Causes of hemolytic anemia in dogs include autoimmune dysfunction, an underlying disease or exposure to a toxin, says VCA Animal Hospitals. The most common diseases that result in hemolytic anemia are cancer and neoplasia.
Canine hemolytic anemia is defined as either primary or secondary, according to VCA Animal Hospitals. In primary hemolytic anemia, a dog's immune system produces antibodies that target and destroy its own red blood cells. Approximately 75 percent of cases are defined as primary. In secondary cases, disease processes or toxins, such as cancer or snake venom, alter the surface of the red blood cells, causing the dog's immune system to falsely recognize them as a threat and then destroy them.