Parasites

• Parasite infection can cause diarrhea in poultry. Common parasites found in poultry with diarrhea include coccidia and roundworms. These parasites cannot be seen with the naked eye. A microscope is needed to find the eggs in the stool.
  
  

Blackhead

• Turkeys are affected by Blackhead caused by the cecal worm, Heterakis gallinae. Chickens are not affected by this worm, but can pass it on to turkeys.
  
  

Bacteria

• Many bacteria can cause infection in poultry. Some bacteria that have diarrhea as a primary symptom include Escheria coli (E. coli) and Pasteurella multocida, the bacteria that causes fowl cholera.
  
  

Salmonella Infections

• Fowl typhoid, caused by the bacterium Salmonella gallinarum, is another cause of diarrhea. The bacterium Salmonella pullorum causes Pullorum, also known as white diarrhea.
  
  

Erysipelas

• Turkeys are especially vulnerable to erysipelas, caused by the bacterium Erysipelothrix rhusiopathiae. Ducks can also contract this disease.
  
  

Viruses

• Many viruses can cause a bird to have diarrhea. Avian influenza and Newcastle disease are two viral diseases that cause diarrhea in poultry. Rotaviruses are also a leading cause of poultry diarrhea.