Preliminary Investigation into Antibiotic Resistance Patterns of Bacteria from Nasal and Rectal Cultures from Florida Manatees (Trichechus manatus)
Abstract
Antibiotic resistance of bacterial pathogens is currently considered a public health threat.4 The origins of resistance are somewhat controversial and in some areas theoretical but include hospitals, human and non-human patients on medications at home, and animal agricultural and wildlife treatments as potential sources that may provide drugs or resistant organisms pathways into the environment.3,5 Trichechus manatus can be used as a model for ecosystem health surveillance because of their long lifespan and coastal lifestyle.1,2 Their vegetarian diet and close proximity to development and industrial sewage effluent exposes them to a variety of possible chemicals and pathogens. In this pilot study, susceptibility to antimicrobials was determined for 50 isolates from 15 different wild manatees from health assessments in the natural environment collected from nasal and anal swabs. Isolates included both gram-positive and negative strains of environmental flora, primary pathogens and opportunistic pathogens, including those with zoonotic potential. The most frequently cultured organisms in descending order were Escherichia coli, Aeromonas sobria, Aeromonas veronii DNA group 10, Aeromonas hydrophila, Pseudomonas aeruginosa, Serratia marcescens, and Pasteurella multocida ss multocida. Of all isolates, 24% demonstrated no resistance. The organisms that demonstrated the highest amount of resistance in descending order were Pseudomonas aeruginosa, Aeromonas hydrophila, Serratia marcescens, Kluyvera cryocrescens, and Shewanella putrefaciens. The antibiotics with the most resistance against them in descending frequency were clindamycin, amp/sulbactam, cefoxitin, cefazolin, and penicillin. In addition to the concerns over human health effects, antimicrobials are an important therapeutic tool for treatment of injured and ill manatees undergoing rehabilitation. These findings may help improve selection of appropriate antibiotics for treatment of their bacterial diseases and how the animals and their treatment environments may be approached to decrease resistance passage to the wild from this source.
Acknowledgements
The authors would like to thank the University of Florida Aquatic Animal Health Program, Nadia Clark, Rebecca Richardson, and Xiaoling Wang in the Microbiology Department, the Tropical Aquaculture Lab and Dr. Jeffrey E. Hill, the Marine Animal Disease Lab and Heather Maness, Dr. Jim Wellehan and Linda Archer.
* Presenting author
+ Student presenter
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