Theses and Dissertations

Issuing Body

Mississippi State University


Hanson, Larry A.

Committee Member

Cunningham, Frederick L.

Committee Member

Petrie-Hanson, Lora

Date of Degree


Document Type

Graduate Thesis - Open Access


Veterinary Medical Science

Degree Name

Master of Science


College of Veterinary Medicine


Aeromonas hydrophila is a Gram-negative, rod shaped, facultative anaerobic bacterium that is ubiquitous to freshwater and slightly brackish aquatic environments and can cause infections in fish, humans, reptiles, and avian species. Recent severe outbreaks of disease in catfish aquaculture have been associated with a highly virulent Aeromonas hydrophila strain (VAH) that is genetically distinct from less virulent strains. Given that A. hydrophila is known to infect birds, we hypothesized that fish eating birds may serve as a reservoir for VAH and spread the pathogen by flying to uninfected ponds. Great Egrets were used in this transmission model because these wading birds frequently predate catfish farms. We found that Great Egrets that were fed VAH infected catfish shed VAH demonstrating their potential to spread VAH. Histologically there were changes found in selected tissue samples.



Virulent Aeromonas Hydrophila (VAH)||Aeromonas hydrophila||Ictalurus punctatus||aquaculture||Adrea alba