Internal Parasites in Chickens

Red chicken outside
Internal Parasites can be classified into two basic groups, worms and protozoa.
Parasitic disease differs from bacterial and viral disease in specific ways:
  • Parasites have a complex lifecycle.

  • Parasites are transmitted from bird to bird differently than viruses or bacteria.

  • Serology (blood analysis) doesn’t work for diagnosing parasites.

  • Quarantine and disinfection are of little use in controlling parasites.

Modern commercial confinement systems have significantly reduced the incidence of worm infestation by limiting the bird’s access to many parasites’ alternate hosts. On the other hand,
confinement systems and high-density stocking rates have led to an increase in the incidence of protozoan parasitic disease in these flocks.
Intestinal parasites - worms - are common in backyard and free-range flocks. Low levels of parasitism don’t usually cause a problem. If the infestation becomes severe, however, worms can lead to significant losses of production, feed efficiency, and overall health.
Download the Resource for the complete printable fact sheet.