Effects of androgenic gland ablation on growth, sexual characters and spermatogenesis of the white shrimp,Litopenaeus vannamei(Decapoda: Penaeidae) males

Abstract

This research was implemented to study the effects of androgenic gland ablation in the white shrimp Litopenaeus vannamei to explore sex reversal potential as an alternative technology for monosex female mariculture based on the sex dimorphic growth of this species. The surgical procedure was applied to male postlarvae (PL) at different ages, after external sex differentiation, as well as in sex undifferentiated PL. Andrectomized males regenerated normal appendices including pereiopods and pleopods; however, body growth and relative size of regenerated petasmas and appendices masculinae were statistically inferior (P ˂ 0.05) to control males. Spermatogenesis in andrectomized males was active, but a phenomenon of degradation of spermatids and reproductive tissues was detected. No sex reversal was accomplished regardless of PL age from sex undifferentiated stages (PL38) to sex differentiated stages (˃PL55). The complete regeneration of sexual characters in andrectomized L. vannamei (Dendrobranchiata) is different from previous reports from Decapoda.

Implant recognition and gender expression following ampoule-androgenic gland implantation in Litopenaeus vannamei females (Penaeidae)

“…and 26% at 37 mm T.L. (Alfaro-Montoya et al, 2015). Therefore, the survival rates measured in the present study (32 and 49%) seem comparable to previous studies.…”

“…In penaeid shrimps, sex reversal has not been accomplished by any means yet (Alfaro-Montoya et al, 2015). However, higher growth rates for females have been demonstrated in Penaeus monodon and Litopenaeus vannamei (Gopal et al, 2010;Alfaro-Montoya et al, 2015), suggesting that monosex shrimp culture is a biotechnological alternative for the industry (Ventura and Sagi, 2012).…”

“…In penaeid shrimps, sex reversal has not been accomplished by any means yet (Alfaro-Montoya et al, 2015). However, higher growth rates for females have been demonstrated in Penaeus monodon and Litopenaeus vannamei (Gopal et al, 2010;Alfaro-Montoya et al, 2015), suggesting that monosex shrimp culture is a biotechnological alternative for the industry (Ventura and Sagi, 2012). Moreover, the mechanism of sex determination has not been confirmed, but some evidence, like sex-linked markers on the maternal map, indicate that penaeid shrimps may have a mechanism similar to M. rosenbergii, with females being heterogametic (ZW; Benzie et al, 2001;Staelens et al, 2008;Zhang et al, 2007;Robinson et al, 2014).…”

“…Moreover, the mechanism of sex determination has not been confirmed, but some evidence, like sex-linked markers on the maternal map, indicate that penaeid shrimps may have a mechanism similar to M. rosenbergii, with females being heterogametic (ZW; Benzie et al, 2001;Staelens et al, 2008;Zhang et al, 2007;Robinson et al, 2014). The location and morphology of the presumptive AG in L. vannamei were recently reported (Vázquez-Islas et al, 2014;Alfaro-Montoya et al, 2015) and the IAG gene was sequenced (Vázquez-Islas et al, 2014); however, there is no confirmation of actual IAG release from identified AG by means of Immunocytochemistry.…”

Avances biotecnológicos sobre maricultura en Costa Rica. Una revisión de la investigación desarrollada por la Escuela de Ciencias Biológicas de la Universidad Nacional

“…Recientemente, se evaluó el potencial de la ablación de la glándula androgénica para la reversión sexual en L. vannamei como alternativa biotecnológica para la producción de cultivos monosexuales de hembras. Los machos a los que se les removió la glándula androgénica presentaron reducción en el crecimiento, regeneración de caracteres sexuales, espermatogénesis activa y degradación de espermátides y tejidos reproductivos, por lo tanto, no fue posible una reversión sexual total (Alfaro-Montoya, Hernández-Noguera, Vega-Alpízar & Umaña-Castro, 2015).…”