Sex Control in Fish with Particular Reference to Salmonids

Abstract

Techniques for sex control in trout, char, and salmon are reviewed in the context of their application to salmonid culture. Procedures for the production of all female, male, or sterile salmonids using estrogen or androgen treatment, respectively, are described and compared for Salmo, Salvelinus, and Oncorhynchus species. The production of homozygous monosex salmonids by radiation gynogenesis and techniques for the production of potentially sterile triploid and polyploid salmonids arc discussed. Finally, alternative sterilization techniques which do not depend on steroid administration or zygote manipulation are reviewed including irradiation, and autoimmune and surgical procedures. Direct and indirect hormonal techniques for production of all female salmonid groups are now sufficiently developed to permit pilot application as is the direct androgen sterilization technique. The procedure of radiation gynogenesis is available for the rapid experimental production of inbred lines. On the other hand, further work is required to determine the effectiveness of induced triploidy and polyploidy as sterilization procedures.Key words: sex reversal, estrogen, androgen, sterilization, gynogenesis, androgenesis, polyploidy, Salmo, Oncorhynchus, Salvelinus