Theses and Dissertations

Date of Award


Document Type


Degree Name

Master of Science (MS)


Ocean, Coastal, and Earth Sciences

First Advisor

Dr. MD Saydur Rahman

Second Advisor

Dr. Alejandro Fierro Cabo

Third Advisor

Dr. Ying Jia


American oyster (Crassostrea virginica) is a popular seafood for its delicacy and high nutritional value. Based on increasing concern about contamination of bacterial pathogens in raw oyster, my research objectives have been focused on detection and enumeration of two important bacterial pathogens, Escherichia coli and Salmonella spp. in the American oyster in south Texas waters, local markets and controlled laboratory studies. Immunohistochemical and RT-PCR analyses showed substantial bacterial pathogen’s presence in gills and digestive glands of oysters collected from San Martin Lake and South Padre Island as well as local markets. Laboratory studies showed increasing trend of both bacterial pathogens with elevated temperatures (28 and 32 °C) compared to control (24 °C). Extrapallial fluid, an important body fluid, glucose levels, pH, and protein concentration varied in oysters and appeared to be pertinent with pathogen intensity. Collectively, these results suggest that American oyster is prone to water-borne pathogen contamination in south Texas waters.


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