Genetic variation at three polymorphic loci in wild and hatchery stocks of the abalone, Haliotis tuberculata Linnaeus

Copyright (c) 1996 Elsevier Science B.V. All rights reserved. The abalone, Haliotis tuberculata, is a gastropod mollusc of commercial importance in Europe with considerable potential for aquaculture. A wild population of H. tuberculata from Guernsey, Channel Islands was compared to two hatchery populations; one an F1 stock produced by a hatchery in Guernsey, the other an F3 stock cultured at the Shellfish Research Laboratory (SRL) at Carna, Ireland. The F1 and SRL stocks were each derived from the Guernsey wild population and reproductively isolated from this population for one and three generations, respectively. The three populations were screened for allozyme variation at three polymorphic loci, Gpi, Pgm and Mdh, using starch-gel electrophoresis. When compared with the wild population, both the F1 and SRL samples were very similar in terms of mean effective number of alleles per locus and levels of heterozygosity. However, the SRL stock did show a reduced number of rare alleles when compared to the F1 and Guernsey samples but without showing any evidence of inbreeding or reduction in levels of heterozygosity. Effective population size was calculated from direct census (Ne) and temporal changes in allelic frequencies (&Ncirc;k). Ne was estimated to be 48 and 54.5 for SRL and F1, respectively, whereas calculated &Ncirc;k was 21.4 and 23.9, respectively.