Genetic determination and temperature effects on turbot Scophthalmus maximus sex differentiation : An investigation using steroid sex-inverted males and females

• Published in: Aquaculture
• Main Authors: Haffray, Pierrick, Lebègue, Elisabeth, Jeu, Sylvie, Guennoc, Michel, Guiguen, Yann, Baroiller, Jean-François, Fostier, Alexis
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2009
• Subjects: L53 - Physiologie animale - Reproduction; M12 - Production de l'aquaculture; Scophthalmus maximus; Détermination du sexe; Différenciation sexuelle; Stéroïde; Température; Génétique; http://aims.fao.org/aos/agrovoc/c_6872; http://aims.fao.org/aos/agrovoc/c_14226; http://aims.fao.org/aos/agrovoc/c_26822; http://aims.fao.org/aos/agrovoc/c_7407; http://aims.fao.org/aos/agrovoc/c_7657; http://aims.fao.org/aos/agrovoc/c_3222; http://aims.fao.org/aos/agrovoc/c_5637; http://aims.fao.org/aos/agrovoc/c_3081; Turbot
• Online Access: http://agritrop.cirad.fr/549966/; http://agritrop.cirad.fr/549966/1/document_549966.pdf; https://doi.org/10.1016/j.aquaculture.2009.05.004; http://catalogue-bibliotheques.cirad.fr/cgi-bin/koha/opac-detail.pl?biblionumber=204858

The relative roles of genetic (GSD) and temperature sex determination (TSD) were investigated in turbot, Scophthalmus maximus, with the objective of producing all-female stocks for aquaculture. Androgen treated males (ATM) and oestrogen treated females (OTF) were produced after testing various 17?-methyltestosterone or 17?-oestradiol treatments delivered orally (3 or 5 mg steroids/kg food) from 35 days postfertilization (dpf) during either 500 or 700 degree-days respectively. GSD was analyzed by checking the sex ratio of families (n=33) obtained by crossing control parents with other control parents, either ATM or OTF. TSD was investigated on 8 families reared at three temperatures (15 °C, 17 °C or 24 °C) from weaning to 100 dpf. All the steroid treatments were efficient in producing either 100% male or 100% female populations demonstrating the production of androgen sex-inversed males and oestrogen sex-inversed females. The results of the GSD analysis suggested that most of the data fit to a ZZ/ZW model of sex determination. However, some crosses deviated from this model and other minor factors may be involved. Interestingly, minor effects of temperature and a limited but significant interaction between family and temperature have been observed. In conclusion, the present data suggest that a major ZZ/ZW genetic model is involved in turbot sex determination. Unexpected sex ratios deviating from this model are discussed, including a possible minor effect of environmental factors, such as temperature.