Degree Type


Date of Award


Degree Name

Master of Science


Animal Science



First Advisor

Mark Rasmussen


Avian pathogenic Escherichia coli (APEC) is an extra-intestinal pathogenic E. coli (ExPEC) pathotype that causes avian colibacillosis, resulting in a major economic loss to the poultry industry annually. It’s not known to directly cause disease in humans, however APEC is able to transmit its plasmid-encoded virulence genes to human ExPEC pathotypes (UPEC and NMEC) or commensal microorganisms present in the human GI tract. This could potentially result in the creation of more virulent or antibiotic resistant strains and classifies APEC as potentially zoonotic. Increased regulation of antibiotic usage as growth promoters and disease preventatives in food animals has resulted in a push towards antibiotic alternatives. Original XPCTM (Diamond V, Cedar Rapids) is a Saccharomyces cerevisiae fermentation product that has proved efficacious as a growth promoter and in reducing different pathogens across numerous animal species. Ceca from poultry provided a diet with this feed additive were collected at the time of slaughter, reconstituted in Luria Broth, plated on Xylose Lysine Deoxycholate selective and differential media, and E. coli colonies were assayed for the presence of APEC and subjected to an antibiogram. The presence of APEC in each cecum was determined utilizing a pentaplex PCR and individual E. coli isolates were tested for resistance against three antibiotics: ceftiofur, enrofloxacin, and chloramphenicol. Results revealed an overall reduction in both APEC prevalence and antibiotic resistance, supporting XPC as a useful alternative to antibiotics in the poultry industry.


Copyright Owner

Jasmine Carroll



File Format


File Size

59 pages

Included in

Microbiology Commons