First evaluation of resistance to both a California OsHV-1 variant and a French OsHV-1 microvariant in Pacific oysters
|Author(s)||Divilov Konstantin1, Schoolfield Blaine1, Morga Benjamin2, Dégremont Lionel2, Burge Colleen A.3, Mancilla Cortez Daniel4, Friedman Carolyn S.5, Fleener Gary B.4, Dumbauld Brett R.6, Langdon Chris1|
|Affiliation(s)||1 : Department of Fisheries and Wildlife, Coastal Oregon Marine Experiment Station, Oregon State University, Hatfield Marine Science Center, Newport, Oregon, USA
2 : Laboratoire de Génétique et Pathologie des Mollusques Marins, Ifremer, La Tremblade, France
3 : Institute of Marine and Environmental Technology, University of Maryland Baltimore County, Baltimore, Maryland, USA
4 : Hog Island Oyster Co., Marshall, California, USA
5 : School of Aquatic and Fishery Sciences, University of Washington, Seattle, Washington, USA
6 : United States Department of Agriculture-Agricultural Research Service, Hatfield Marine Science Center, Newport, Oregon, USA
|Source||Bmc Genetics (1471-2156) (Springer Science and Business Media LLC), 2019-12 , Vol. 20 , N. 1 , P. 96 (9p.)|
|WOS© Times Cited||19|
|Keyword(s)||Ostreid herpesvirus 1, Crassostrea gigas, Heritability, Breeding|
Variants of the Ostreid herpesvirus 1 (OsHV-1) cause high losses of Pacific oysters globally, including in Tomales Bay, California, USA. A suite of new variants, the OsHV-1 microvariants (μvars), cause very high mortalities of Pacific oysters in major oyster-growing regions outside of the United States. There are currently no known Pacific oysters in the United States that are resistant to OsHV-1 as resistance has yet to be evaluated in these oysters. As part of an effort to begin genetic selection for resistance to OsHV-1, 71 families from the Molluscan Broodstock Program, a US West Coast Pacific oyster breeding program, were screened for survival after exposure to OsHV-1 in Tomales Bay. They were also tested in a quarantine laboratory in France where they were exposed to a French OsHV-1 microvariant using a plate assay, with survival recorded from three to seven days post-infection.
Significant heritability for survival were found for all time points in the plate assay and in the survival phenotype from a single mortality count in Tomales Bay. Genetic correlations between survival against the French OsHV-1 μvar in the plate assay and the Tomales Bay variant in the field trait were weak or non-significant.
Future breeding efforts will seek to validate the potential of genetic improvement for survival to OsHV-1 through selection using the Molluscan Broodstock Program oysters. The lack of a strong correlation in survival between OsHV-1 variants under this study’s exposure conditions may require independent selection pressure for survival to each variant in order to make simultaneous genetic gains in resistance.