Postmortem Survey of Disease Conditions in Backyard Poultry

The laboratory information systems of the Avian Health and Food Safety Laboratory (AHFSL) and the California Animal Health and Food Safety Laboratory System (CAHFS) were analyzed to determine the disease frequency, by etiology, for backyard chicken submissions. Marek’s disease and Escherichia coli infection were by far the most common disease conditions diagnosed in both laboratories (17.7% and 17.4% at AHFSL versus 14.5% and 13.5% at CAHFS), followed by coccidiosis (AHFSL = 5.9%, CAHFS = 3.8%), ascaridiasis (AHFSL = 5.6%, CAHFS = 3.1%), and Mycoplasma gallisepticum (AHFSL = 3.2%, CAHFS = 3.6%). Neoplasia of the reproductive tract, ascites syndrome, and fatty liver hemorrhagic syndrome were found at a higher rate at AHFSL (13.9%, 8%, and 5.1%, respectively) than at CAHFS (1.6%, 1%, and 1.8%, respectively). This difference might have been related to the flock purpose and age of birds submitted. The 2 notifiable diseases of poultry, Newcastle disease and avian influenza, are rare in backyard poultry and neither of these diseases was diagnosed during the investigated period.