Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Monosex female production in the silver barb (Puntius gonionotus Bleeker).

Abstract

Gynogenetic female silver barbs (Puntius gonionotus) were reared on artificial plankton containing 25-150 mg 17α-methyltestosterone (MT)/kg for 3-5 weeks starting 1-3 weeks after hatching. The highest percentages of males (33.9 and 29.8% males respectively) were found after treatment with 25 mg MT/kg for 4 or 5 weeks, starting at 2 weeks post-hatch. The majority of crosses between such males and ordinary females gave all-female progeny, which supports the hypothesis of female homogamety and establishes that large-scale production of monosex females is feasible in this species. A growth trial comparing monosex female groups with mixed-sex groups in pond culture showed an increase in total pond yield by 28.7% at 5 months and 22.9% at 7 months for the all female groups.