SREL Reprint #3605

Microbiota of four tissue types in American alligators (Alligator mississippiensis) following extended dietary selenomethionine exposure

Troy J. Kieran1, Samantha J. Goodman2, John W. Finger Jr1,3, Jesse C. Thomas IV1,
Matthew T. Hamilton3, Tracey D. Tuberville3, and Travis C. Glenn1

1Department of Environmental Health Science, University of Georgia, Athens, GA 30602, USA
2Department of Poultry Science, University of Georgia, 30602 Athens, GA, USA
3Savannah River Ecology Laboratory, University of Georgia, 29802 Aiken, SC, USA

Abstract: Selenium represents an essential trace nutrient that is necessary for biological functions. Defciencies can induce disease, but excess can induce toxicity. Selenium defciency is a major concern in underdeveloped countries, while also posing as a toxic pollutant in waterways surrounding landflls, agricultural areas, and fossil fuel production sites. We examined the microbiome of selenomethionine (SeMet) fed American alligators (Alligator mississippiensis) at the beginning and end of a 7-week exposure experiment. Alligators were randomly divided into three groups: control and 1000 or 2000 ppm SeMet. DNA from before exposure (oral and cloaca swabs) and post-exposure (oral, cloaca, small & large intestines) sampling were extracted and amplifed for bacterial 16 s rRNA. While treatment did not seem to have much efect, we observed a predominance of Fusobacteriaceae and Porpyromonodaceae across all tissue types. Cetobacterium and Clostridium are the most abundant genera as potential indicators of the aquatic and carrion feeding lifestyle of alligators.

Keywords: Microbiome; Crocodilian; Selenium; Toxicology

SREL Reprint #3605

Kieran, T. J., S. J. Goodman, J. W. Finger Jr., J. C. Thomas IV, M. T. Hamilton, T. D. Tuberville, and T. C. Glenn. 2020. Microbiota of four tissue types in American alligators (Alligator mississippiensis) following extended dietary selenomethionine exposure. Bulletin of Environmental Contamination and Toxicology 105(2020): 381-386.

This information was provided by the University of Georgia's Savannah River Ecology Laboratory (srel.uga.edu).