Characteristics and Cryopreservation of Semen of Sex-Reversed Females of Salmonid Fish

Abstract

Sex reversal has been used as a breeding strategy by salmonid fish to produce genetically and phenotypically single sex populations. Production of all-female fish has great importance for the creation of monosex female triploids of salmonid fish, which are valued for their sterility, lack of female maturation, and larger commercial size. Among salmonids, the majority of rainbow trout (Oncorhynchus mykiss) production is based on all-female production with a high proportion of all-female triploid production in Europe. The main aim of this review is to present the recent knowledge regarding sex-reversed females (SRFs) of salmonid fish. We discuss the methods of sex reversal as well as their effects on the morphology and histology of the reproductive tract. We focus on the characteristics of SRF semen as well as the factors determining semen quality. The lower quality of SRF sperm compared to that of normal males has resulted in the need for the artificial maturation of semen. Most importantly, methods of semen storage—both short-term and long-term (cryopreservation)—that can improve hatchery operations are presented with the special emphasis on recent progress in development of efficient cryopreservation procedures and use of cryopreserved semen in hatchery practice. Moreover, we also address the emerging knowledge concerning the proteomic investigations of salmonid sperm, focusing primarily on the proteomic comparison of normal male and SRF testicular semen and presenting changes in SRF rainbow trout sperm proteome after in vitro incubation in artificial seminal plasma.

Metabolomics in salmonid aquaculture research: Applications and future perspectives

“…Although their toxicities may be established from other biological endpoints, metabolomics may provide insights at a species‐ and/or environment‐specific level. In addition, the biodegradation mechanisms of sex reversal hormones used in commercial salmon production is another area falling within this research theme, where metabolomics could deliver value 230 …”

“…In addition, the biodegradation mechanisms of sex reversal hormones used in commercial salmon production is another area falling within this research theme, where metabolomics could deliver value. 230 A changing physical environment due to climate change is of concern in many regions where water temperatures already are close to or fluctuate at the boundary of thermal limits for different species.…”