Disease Prevalence and the Population Genetic Structure of Crassostrea virginica Along the Georgia Coast
Term of Award
Master of Science in Biology (M.S.)
Document Type and Release Option
Thesis (open access)
Copyright Statement / License for Reuse
This work is licensed under a Creative Commons Attribution 4.0 License.
Department of Biology
J. Scott Harrison
Committee Member 1
Committee Member 2
The Eastern Oyster, Crassostrea virginica, is an ecologically important species that plays a role in protecting shorelines, water filtration, and providing habitat and food for various fish species. Perkinsus marinus and Haplosporidium nesloni are two pathogens currently affecting oyster populations. These pathogens have both been documented as causes of mass mortality events along the East coast. They greatly diminish the health of oysters, resulting in the degradation of oyster tissue, reduction in growth and reproductive ability, and may cause death. In this study, wild oysters were collected from eleven locations along the Georgia coast to investigate the presence, intensity, and impact on the health of local populations. The condition of each oyster was calculated during processing, and qPCR was used to determine the presence and intensity of both P. marinus and H. nelsoni. Additionally, population genetic structure and kinship within and among populations was examined using 20 microsatellite loci. Results showed that >90% of oysters tested were infected by one or both pathogens, and 48.8% of these were cases of co-infection. Intensity of infection varied significantly across sites for both P. marinus and H. nelsoni (p = <0.0001, p = <.0001, respectively). Across sites, variation in oyster condition was driven by a single study site exhibiting higher oyster condition (p = <0.0001), however, being infected had no effect on oyster condition (p = 0.071), and neither did infection intensity of either pathogen (p = 0.346, p = 0.819). There was evidence supporting the theory of sweepstakes reproductive success among Georgia oyster populations; fine-scale population structure was detected, however, there was no link to geographic location. Additionally, oyster kin were found to be more likely to settle near each other (p = <0.0001).
Batchelor, Sarah, "Disease Prevalence and the Population Genetic Structure of Crassostrea virginica Along the Georgia Coast" (2021). Electronic Theses and Dissertations. 2347.
Research Data and Supplementary Material
Genetics Commons, Marine Biology Commons, Molecular Genetics Commons, Parasitology Commons