Master of Science (MS)
The sale of eastern oysters (Crassostrea virginica) is a multi-million dollar industry in the United States. Triploid production of oysters helps to alleviate the decline in sales during summer months that normally results from the loss of flavor and texture when diploid oysters are spawning. Research to improve the ease of triploid production is critical for the expansion of oyster hatcheries producing triploids. The goals of this research were to determine the period of time when triploid oysters are most fertile and to determine if prostaglandin E2 (PGE) plays a role in oocyte maturation of C. virginica. The results of this research will assist in creating triploid broodstock for tetraploid production. Triploid oysters were found to reach full gonadal maturity as well as spawn, however at lower percentages than diploid oysters. In this study, diploid oysters peaked in maturity from April 18-May 07. Triploid oysters peaked in maturity in early February and had two smaller peaks in early June and mid August. This suggests that triploid development is shifted from diploid development and should be spawned either earlier or later in the year than diploids. Oysters with oocytes in early development (stage II) continually increased PGE titers through stages III and IV. Once oysters were ready for spawning in stage V, titers decreased in value. This correlation of PGE titers with gonadal stage suggests that PGE plays a role in the early maturation phase of oocytes. PGE titers were not significantly different when compared to 2N and 3N cohorts or amongst gonadal stages. The lack of significance may be due to high variability as a result of random sampling.
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Young, Esther Faith, "Reproduction in female diploid and triploid eastern oysters (Crassostrea virginica): comparison of gonadal changes correlated with prostaglandin E2" (2010). LSU Master's Theses. 4035.
Lynn, John W.