Aquaculture America 2024

February 18 - 21, 2024

San Antonio, Texas

GENETIC PARAMETERS FOR GROWTH TRAITS IN GULF OF MEXICO EASTERN OYSTER FAMILIES REARED IN HIGH AND LOW SALINITY ENVIRONMENTS

Heather King*, William Walton, Huiping Yang, Leslie Sturmer, Christopher Hollenbeck, John Scarpa, Brian Callam, Jim Stoeckel, Scott Rikard, Megan Gima, Jason Stannard, Kelly Lucas, Andrea Tarnecki, Eric Saillant

Auburn University Shellfish Lab

Auburn University

Dauphin Island, AL

Hnk0012@auburn.edu

 



 

 The eastern oyster (Crassostrea virginica) supports large markets throughout the eastern United States. In recent decades, wild stocks have observed major declines across the species’ range including in the Gulf of Mexico (Gulf). In 2019, the SALT consortium initiated a breeding program to support the developing industry in the Gulf with oysters bred for improved performance in different salinity environments. In September of 2020, the first generation was produced using 102 males and 102 females collected from 17 natural reefs between San Antonio Bay (Texas), and Cedar Key (Florida).

Families were bred according to a 2 x 2 factorial crossing design, pooled for common garden culture, and deployed at 7 growout sites in April 2021. At the end of the growout period, four sites were selected that represented high (AH) and low (MB, USM, LSU) salinity environments based on salinity conditions recorded during the growout period. The 204 founders and 6,414 offspring were assayed at 192 Single Nucleotide Polymorphism markers and the obtained genotypes were used to assign offspring to parent pairs using a likelihood ratio approach. Genetic parameters were estimated using animal mixed models in ASREML v.4.2. Estimates of heritability at low salinity ranged between 0.63 ± 0.06 and 0.84 ± 0.05 and were significantly higher than the estimate obtained at the high-salinity site (0.38 ± 0.08). Estimates of dominance variance did not differ significantly from zero. Genotype x environment correlations for growth rate ranged from 0.62 to 0.99 and were highest between low salinity sites (Table 2).