Department of Genetics

Permanent URI for this community

https://scholar.sun.ac.za/handle/10019.1/21

Browse

Browsing Department of Genetics by Subject "Abalone culture -- South Africa -- Gansbaai"

Now showing 1 - 1 of 1
  • Thumbnail Image
    Item
    Molecular analysis of genetic variation and relationships amongst abalone (Haliotis midae) at the I&J abalone hatchery at Danger Point, Gansbaai, R.S.A.
    (Stellenbosch : Stellenbosch University, 2002-12) Lambrechts, Daneel; Brink, Danie; D'Amato, M. E.; Stellenbosch University. Faculty of AgriSciences. Dept. of Genetics.
    ENGLISH ABSTRACT: The species Haliotis midae is the only abalone species of commercial importance to the South African fisheries industry. The species is currently under substantial pressure due to commercial harvest and illegal poaching, to the extent that genetic and biodiversity may be under threat. The species is also being cultured in commercial systems for supply to international markets. The South African production for 2002 amounted to 350 tons. The commercial production of abalone may also have implications with regard to genetic diversity of natural and commercial populations. The aim of this project was to assess the genetic diversity of the natural and commercial populations of abalone at the I&J Abalone Farm, Danger Point, Gansbaai, in South Africa, in order to make recommendation with regard to possible impact on natural diversity as well as internal management systems. Distortion of natural genetic diversity or a loss of internal diversity will have detrimental consequences. Representative samples have been obtained from the surrounding natural population, as well as the commercial populations, including the broodstock and various progeny groups. Both mtDNA and AFLP molecular techniques were used to assess genetic diversity. Data analysis showed that the genetic profile of the commercial population display sufficient genetic variation. The genetic structure of the commercial population also displays no significant deviation from that of the surrounding natural population, i.e. the population of origin. The results through give indication of a small, though unsignificant loss of genetic variation from the broodstock to the subsequent progeny groups. The investigation conclude that the commercial populations of abalone at the I&J Abalone Farm, Danger Point, Gansbaai, in its current format holds no threat to the disruption of the genetic diversity of the surrounding natural population. Further, the commercial population possesses sufficient genetic variation in view of future genetic development. There is signs of a slight loss of genetic variation in the change over from the broodstock to the progeny groups. This would necessitate careful and controlled replacement of the original broodstock with new animals from the commercial progeny groups as part of an ongoing process of domestication.