Abstract
Ph.D. (Zoology)
The contribution of genetics in animal husbandry and agriculture
has long been recognised. The application of genetics in fish
culture has not yet become established because both overseas and
locally the focus was until recently still on culture techniques.
In South Africa the only genetic data on the rainbow trout
(Parasalmo mykiss) stock is limited to one electrophoretic
survey (Op't Hoff et al. 1982).
During 1982 to 1985 a survey was done of trout angling management
in provincial trout angling waters by the Transvaal Division of
Nature Conservation. The goal was to find and eliminate inhibiting
factors affecting trout angling in order to provide a
better service. Angling results were improved and management of
trout waters brought into line with its own potential. The
percentage returns of trout caught however, seemed to reach a
level that could only be breached by genetically improving the
trout strains used for stocking.
The inherent inability of inbred domesticated P. mykiss strains
to grow and survive in nature has been shown to affect its
survival when stocked in streams and dams for angling purposes
(Kincaid 1981; Ersbak & Haase 1983).