Population Genetic Comparisons among Cobia from the Northern Gulf of Mexico, U.S. Western Atlantic, and Southeast Asia

Abstract

Nuclear-encoded microsatellites and mitochondrial DNA (mtDNA) sequences were assayed from Cobias Rachycentron canadum sampled in waters offshore of Virginia (U.S. Atlantic), Mississippi and Louisiana (Gulf of Mexico), and Taiwan (Southeast Asia). Global exact tests and analysis of molecular variance revealed that Cobias from U.S. waters were homogeneous for alleles and genotype distributions at 27 nuclear-encoded microsatellites and were homogeneous in mtDNA haplotype distribution, whereas both genetic markers in Cobias from Taiwan differed significantly from those of Cobias in U.S. waters. Based on these genetic differences, use of Cobia broodstock from Southeast Asia in U.S. aquaculture facilities is not recommended. Results are compatible with the use of Cobia broodstock from either the U.S. Atlantic or the Gulf of Mexico for aquaculture at U.S. facilities; caveats to the exchange of broodstock between these two regions are discussed.

Received June 7, 2012; accepted July 16, 2012

ACKNOWLEDGMENTS

We thank B. Falterman, J. Franks, and J. Graves for assistance in procuring specimens from U.S. waters, and K. Burns and J. Franks for comments on a draft of the manuscript. Work was supported by TexasAgriLife (Project H-6703) and by the National Science Council of Taiwan. This paper is Number 89 in the series “Genetics Studies in Marine Fishes” and is Contribution Number 212 of the Center for Biosystematics and Biodiversity at Texas A&M University.