The effects of Gokshura, Tribulus terrestris on sex reversal of guppy, Poecilia reticulata.

This study examined the effects of Tribulus terrestris (TT) on sex reversal in guppy, Poecilia reticulata. The objective of this study was to introduce a new environmentally friendly method for masculinization in P. reticulata. Since male guppy has higher commercial value than female. TT is a natural, non-toxic herb which helps enhance testosterone levels in human and animals. It was prepared in a laboratory in France. Different concentration (0.0, 0.05, 0.1 and 0.15 g L(-1)) of TT was investigated for sex reversal in the Poecilia reticulata. TT extract was administered by immersion of newly born offspring once weekly for two months. Among the dosages used in the present study 0.15 g L(-1) TT was the most effective dosage that ensured maximum male ratio (80%, p < 0.01). Although, sex ratios of 0.05 and 0.1 g L(-1) TT were not significantly different from the expected 1:1 ratio, in these two groups treatment with TT also result in higher number of males (58.25 and 59.77%, respectively), than control (p > 0.05). Total survival rates in all treatments and control were uniformly high ranging from 83 to 87% (p > 0.05). It is concluded that TT has no negative effect on survival rate of P. reticulata. All groups of TT-treated fish exhibited successful growth acceleration comparing to the control group, but only TT treatment at the concentration of 0.15 and 0.1 g L(-1) TT significantly improved growth rate of P. reticulata (p < 0.01). Histological examinations revealed that testes of fish treated with TT-extract contained all stages of spermatogenesis. Sex reversal in P. reticulata demonstrated that TT treated new-born progenies showed successful sex reversal, spermatogenesis and better growth rate than untreated progenies.