1. INVESTIGATING QUANTITATIVE GENETICS AND MARKER-ASSISTED SELECTION FOR IMPROVED GROWTH PERFORMANCE IN BAY SCALLOPS, ARGOPECTENIRRADIANS, IN NORTH CAROLINA, USA
- Author
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Varney, Robin L. and Wilbur, Ami E.
- Subjects
Applied Biosystems Inc. -- International economic relations ,Genetic markers -- Growth -- Investigations ,Genes -- Growth -- Investigations ,Quantitative genetics -- Investigations ,Aquaculture industry -- International economic relations ,Biotechnology industry -- International economic relations ,Single nucleotide polymorphisms -- Growth -- Investigations ,Company legal issue ,Company growth ,Biological sciences ,Zoology and wildlife conservation - Abstract
Severe declines in commercial and recreational fisheries of the bay scallop, Argopecten irradians, and the success of the Chinese industry have led to increased interest in aquaculture in the United States. In recent years, the Chinese industry has sought to improve production through marker-assisted selection and has identified several candidates that may be predictive of performance. We explored the utility of a subset of these markers [size- related quantitative trait loci (QTL) marked by ten microsatellites and four single nucleotide polymorphisms (SNP) in the myostatin gene] to improve the growth performance of bay scallops in North Carolina (NC) using quantitative genetics and marker- assisted selection. Mature scallops were collected from three wild populations in the fall of 2019 in Topsail Sound, Core Sound, and Bogue Sound. The wild scallops were brought back to the University of North Carolina Wilmington (UNCW) Shellfish Research Hatchery (SRH), and each group was spawned separately. The wild scallops were genotyped at the 14 markers to confirm their presence in NC populations. The 2019 offspring lines were genotyped, and growth monitored to evaluate the association of the microsatellite and myostatin SNP genetic markers with growth performance. Except for a single marker in a single line, no association of the markers with growth metrics was observed. Consequently, in the fall of 2020, performance-based selection was implemented by sorting 2019 lines into 'Big' and 'Little' groups based on shell height and spawned separately. Evaluation of microsatellite and SNP genetic markers in broodstock scallops revealed significant genetic differences among the size groups; however, no consistent significant association between the genetic markers and performance was observed in broodstock scallops. Offspring of the size-sorted groups were deployed to three NC aquaculture farms in April 2021 and monitored for 7 mo. Overall survival ranged from 3% on Farm B (terminated in August 2021) to 37% on Farm A and was 16% at UNCW (terminated in November 2021). Offspring of the 'Little' broodstock survived better at UNCW (19% versus 14%) but there was no difference at the other two sites. Growth also differed among sites. At UNCW there were no significant differences in any of the growth metrics assessed between the offspring of the 'Big' and 'Little' broodstock; however, there were significant differences between the offspring on Farm A. The 'Little' line was significantly smaller than the 'Big' which was similar in size to the scallops at UNCW except for shell width and adductor muscle weight. The results of this study suggest the genetic markers identified for selective breeding in Chinese bay scallops are not applicable for predicting superior performance in NC bay scallops. KEY WORDS: Argopecten irradians, bay scallop, aquaculture, genetics, growth. North Carolina, INTRODUCTION The bay scallop, Argopecten irradians (Lamarck 1819), is an epibenthic bivalve that occurs in sheltered bays and sounds along the Atlantic and Gulf coasts of the United States. Massachusetts, [...]
- Published
- 2024
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