Masculinization of the gynogenetic juvenile ship sturgeon (Acipenser nudiventrisLovetsky, 1828) using 17α‐methyl testosterone

Abstract

In sturgeons, the induction of gynogenesis and sex reversal could be important for potential production of neomale sturgeon and all‐female progeny for caviar production. The aim of this study was sex reversal of ship sturgeon (Acipenser nudiventris Lovetsky, 1828) gynogen into male sex. Five‐month‐old gynogens were sex reversed into male by including 17α‐methyl testosterone in their food for 7 months. Three treatments were considered as follows: (a) without treated (gynogen control), (b) 10 mg MT/kg diet, and (c) 50 mg MT/kg diet. All treatments (60 individuals) were sampled both the 30 and 36 months old and their sex was determined using classical histology method of gonad. The sex ratio of the progenies in the gynogen control were 73.3% female and 26.7% male. In treatment of 10 mg MT/kg feed, 18 specimens were studied that half of them (50%) showed pseudo‐testicular structure in the female gonad. That is 50% of the specimens were intersex, 27.7% were male and 22.3% were female. All of the fish fed by 50 mg MT/kg feed had been sex reversed to male. Sexual maturation of these fish had been recognized in stage III at 36 months old. In conclusion, 50 mg MT/kg feed found as effective dose for successful sex reversal in gynogenetic ship sturgeon.

Real-Time PCR-Based Method for Sex Determination in Lake Sturgeon (Acipenser fulvescens)

“…Intersex individuals occur in wild and cultured sturgeon popula-tions [16][17][18] and, occasionally, in paddlefish [19]. Intersex individuals have been described in situations of exposure to exogenous sex hormones [17,20,21]; however, it is unclear if these compounds exist in sufficiently high concentrations in the systems that we sampled to cause sex reversal. Sexing errors using the ALLWSex2 marker in lake sturgeon, though small, cannot be considered nonexistent and appear to be biased towards erroneously classifying females as males.…”

First observations of intersex development in paddlefish Polyodon spathula

“…Additional information on intersex fish and sex determination would benefit aquaculture activities. Based on the conservation value of sturgeons as imperilled with simultaneous commercial value as a source of caviar (Williamson, 2003), much ongoing research is related to artificial and environmental cues for sex determination in captive and wild stocks (Hassanzadeh et al ., 2019; Keyvanshokooh and Gharaei, 2010; Muller et al ., 2018; Webb and Doroshov, 2011). In paddlefish aquaculture, chromosomal manipulation to produce females (for caviar production) has been successful using external and chemical stimuli (Mims and Shelton, 1998; Shelton et al ., 2019).…”

Effects of 17α‐methyltestosterone feeding and immersion on masculinization of rosy barbs Pethia conchonius and dwarf gouramis Trichogaster lalius

“…Since this review, the number of species and families in which MT has been tested on has increased. The efficacy of MT on masculinization has also been investigated in the European sea bass Dicentrarchus labrax (Blázquez, Piferrer, Zanuy, Carrillo, & Donaldson, 1995), Japanese flounder Paralichthys olivaceus (Kitano, Takamune, Nagahama, & Abe, 2000), sablefish Anoplopoma fimbria (Luckenbach & Fairgrieve, 2016), mud loach Misgurnus mizolepis (Nam, Noh, & Kim, 1998), ship sturgeon Acipenser nudiventris (Hassanzadeh Saber et al, 2019), and black crappie Pomoxis nigromaculatus (Al‐ablani & Phelps, 1997), among others.…”