Research Project: Characterization of Avian Pathogenic E. coli Field Isolates and Identification of Potential Vaccine Targets in Commercial Poultry

Location: Poultry Research

Project Number: 6064-13000-014-015-A
Project Type: Cooperative Agreement

Start Date: Aug 1, 2024
End Date: Jul 31, 2029

Objective:
1. Continue characterization of Avian Pathogenic Escherichia coli (APEC) isolates. 2. Continue lethality testing. 3. Identify/screen target antigens for vaccine application. 4. Initiate development of APEC challenge models. 5. Development of subunit APEC vaccines from strongly immunogenic antigens (Subobjective 2b).

Approach:
Conventional and real-time PCR will continue to be applied to confirm putative Avian Pathogenic Escherichia coli (APEC) isolates and to determine serogroup typing and antimicrobial susceptibility. An embryo model will be used as in the previous year to assess APEC isolate virulence/lethalilty. Research will continue to identify and screen potential immunological targets as in the previous year. Research will be started to develop challenge models for APEC in broilers, layers, and breeders. Initially 14 d old broilers and day old layer chicks will be vaccinated intramuscularly and subsequently challenged with virulent APEC. ELISA immunoassays and bactericidal assays will be used to compare treatments. In addition, fecal microbiomes and extraintestinal populations of challenging APEC organisms will the quantified and compared among treatments.