|CORBETT, RYAN - University Of Rhode Island|
|GOMEZ CHIARRI, MARTA - University Of Rhode Island|
|MOSS SMALL, JESSICA - Virginia Institute Of Marine Science|
|ALLEN JR., STANDISH - Virginia Institute Of Marine Science|
Submitted to: Journal of Shellfish Research
Publication Type: Abstract Only
Publication Acceptance Date: 1/10/2015
Publication Date: 8/1/2015
Citation: Corbett, R., Gomez Chiarri, M., Moss Small, J., Allen Jr., S., Proestou, D.A. 2015. Characterization of phenotypic variation for dermo resistance among selectively-bred families of the Eastern oyster, Crassostrea virginica. Journal of Shellfish Research. 34(2):620.
Technical Abstract: Dermo disease impacts nearly every region where oysters are cultured in the Eastern U.S. and is a significant concern to industry stakeholders. Efforts to breed for Dermo resistance in the Eastern Oyster have had modest success, yet the range of existing phenotypic variation with respect to Dermo resistance among selectively bred families is not well characterized. The purpose of this study was to quantify the extent of phenotypic variation in the performance of C. virginica families upon exposure to the Dermo-causing parasite Perkinsus marinus under controlled conditions. Oysters (N = 48) from each of 23 families were subdivided into challenged (N = 24) and control (N = 24) groups. Challenged oysters were notched and injected with 5 × 106 cultured Perkinsus cells per gram wet tissue weight while control oysters were injected with sterile salt solution. The two groups were maintained in separate flowing static systems at 25°C and 25 ppt and mortalities were monitored each day for 42 days. Mantle, gill and digestive tissues were sampled from moribund oysters during the experiment as well as survivors at the end of the experiment to assess Perkinsus load. Mortality among challenged oysters varied by family and ranged from 42 to 100%. The difference in mortality between challenged and control groups also spanned a wide range across families (4 – 54%). These results suggest there is ample phenotypic variation in how oyster families respond to Dermo and will be coupled with parasite load data to identify which families best represent Dermo resistant oysters.