Molluscan Broodstock Program/USDA-ARS Pacific Shellfish Breeding Center

History of the Molluscan Broodstock Program

The Molluscan Broodstock Program (MBP) has been producing and selecting Pacific oysters since 1996. The broodstock population is based on six founder cohorts of 50 families each, produced from 600 "wild" oysters collected from different areas on the West coast. This broad founder population, together with implementation of appropriate breeding schemes, has helped reduce the negative effects of inbreeding on family yields.

Cohorts of Pacific oyster families are produced in a pilot-scale hatchery located at the Hatfield Marine Science Center, Oregon State University.  Pedigreed broodstock are spawned and eggs are fertilized with sperm from the appropriate male.  Larvae and juvenile oysters (spat) are reared on algal diets in the MBP nursery.  Spat from each family have been planted at commercial grow-out sites in California, Oregon, Washington and Alaska. Families with the highest survival and yields (meat weights) are identified and crossed to produce subsequent generations for selection. Selected broodstock are provided to industry to enhance commercial production. A repository preserves valuable genetic material for future applications.

MBP has achieved an average increase in yield of 35% (whole live weight) compared with yields of families from unselected broodstock. The West coast oyster industry has made extensive use of MBP broodstock. Future characteristics to be selected include resistance to the highly pathogenic micro-var strains of the oyster herpes virus (OsHv-1 µvar).

Transition to include MBP in the USDA-ARS Pacific Shellfish Breeding Center

As we mentioned in the Spring 2021 COMES Newsletter, MBP is in a time of transition as Dr. Chris Langdon prepares for retirement.  USDA-ARS is expanding at Hatfield, and MBP is becoming part of their new Pacific Shellfish Breeding Center (PSBC). The PSBC is still being brought online, but this program will focus on genetics, breeding and improved production technologies for the Pacific oyster. The research will focus on improving traits that industry growers value, such as growth, disease and stress tolerance, allocation of reproductive effort, triploid survival, shell shape, and shell and meat color.  In particular, disease outbreaks continue to be a major concern, including outbreaks of microvariants of the Ostreid herpesvirus that have caused mass mortalities on shellfish farms in Europe and Oceania. The PSBC will accelerate the pace of improvements by 1) coordinating efforts among programs, 2) applying new genetic tools and increased resources, 3) testing new strains more widely, and 4) advancing production methodologies. Substantial investment for the ARS shellfish program includes funds to support OSU’s continued collaboration on oyster genetics, breeding, and ecology, and we are looking forward to many productive years to come.