Comparison of Disease Resistance Among Heritage Chicken Breeds

Organic poultry farming is uniquely threatened by infectious disease, because organic farming practices increase chicken exposure to parasites and pathogens while simultaneously restricting the use of drugs and chemicals that control infections. “Heritage” chicken breeds, which are commonly used in organic farming, may possess endogenous disease resistance. However, it is unclear how resistance to infection varies among heritage breeds. We hypothesize that heritage chicken breeds differ in susceptibility to infection by intestinal parasites and pathogens. Farmers could use breeds resistant to infection to compose flocks more robust to disease and thus enhance the resilience of the organic poultry industry. To test our hypothesis, we will compare experimental infections among six heritage chicken breeds inoculated with Eimeria sp. (protozoa) or Campylobacter jejuni (bacteria) that affect poultry health (Eimeria) and cause foodborne illness in people (Campylobacter).