Author: Avuntaura    Gulledge

Major: Marine Sciences

Graduation Year: 2020

Thesis Advisor: Paul Rawson

Description of Publication: Genetic improvement of commercial lines has been a key component in the increased production of eastern oysters (Crassostrea virginica). One form of genetic improvement, induced triploidy, is commonly used to produce sterile oysters with faster growth and higher meat quality. However, the details of the physiological advantage provided by triploidy are poorly understood. Whole animal respiration is an important indicator of an individual’s capacity to meet increased energetic demands for growth and stress response. I have developed an assay for the Agilent’s XFe96 Extracellular Flux Analyzer to measure metabolic capacity (i.e., rates of basal, maximal, mitochondrial, and non-mitochondrial oxygen consumption) in intact, recently settled eastern oysters (spat). In developing this assay, I optimized the concentration of two pharmacological agents, carbonyl cyanide 4-(trifluoromethoxy) phenylhydrazone (FCCP) and sodium azide (NaAz), required for estimating maximal and mitochondrial oxygen consumption rates (OCR) in spat samples. I found that 2 μM FCCP and 50 mM NaAz resulted in the best resolution of these partitions. A goal of my research is to use this assay to evaluate the metabolic capacity of oyster lines during the hatchery phase of their production. Thus, I utilized my assay to compare the metabolic capacity of diploid spat from the Rutgers Haskin NEH line to triploid spat from a cross of DEBY diploids and VIMS tetraploids. The triploid spat had increased levels of basal, maximal, and mitochondrial rates. The results of my study suggest that the XFe96 Analyzer provides a valuable platform for measuring metabolic variations among genetically improved oyster lines.

Location of Publication:

URL to Thesis: https://digitalcommons.library.umaine.edu/honors/741