## 4 Discussion
Considering not sufficient and certain data for the effect of _Vitex agmus-castus_ extract on fishes, there is low contrasting recommendations. In the present study, the mean egg diameter, absolute fecundity, GSI, survival, length, and weight of larvae were increased with an increased dose of _Vitex agmus-castus_ extract in the diet (\(p<0.05\)). The highest measured egg diameter was 0.03\(\pm\)0.75 mm that it was in agreement with [PERSON] and [PERSON] (2008) [43]. As confirmed by other research, herbal extract gets improved the growth and reproductive indices. [PERSON] et al. (2014) [44] compared the reproductive effect of extract _Vitex agmus-castus_ and 17\(\upmu\) estradiol (E2) on ovarian tissue of immature female three spot gourami (_Tichogaster trichopterus_). Their results showed that oocytes diameter, fecundity, and fertility enhancement were the most identical for a treated group with extract of _Vitex agmus-castus_. Their results are in agreement with our results. In this experiment the ratio of female to male improved (\(p<0.05\)). Treatment T3 was leaded to 87.23 percent of female production with increasing concentration of extract in the diet. [PERSON] et al. (2014) [44] investigated the Effects of _Origanum vulgar_ extract on ovary morphology and histology in immature _Trichogaster trichopterus_. They found that _Origanum vulgar_ can hasten oocyte maturation. Also, histological studies indicated that _Origanum vulgar_ increased the maturation and growth of oocytes. The former studies on the phytoestrogens compound indicated that phytoestrogens have diverse effects on the different fish species especially on ornamental species. [PERSON] et al. (2014) [45] indicated that Genistein as a phytoestrogen has a limited effect on reproductive endpoints in a female fighting fish Betta splenden, while other researches showed contrast results. Phytoestrogens increased vitellogenin synthesis in Tilapia's primary hepatocytes [46]. [PERSON] and [PERSON] (2009) [47] used the ethanol extract of _Garcinia kola_ seeds to enhance fertility in _C. gariepinus_. Fish were fed with complemented diets in different concentrations (0.25, 0.5, 1.0 and 2.0 g\({}^{-1}\) kg diet) of ethanol extract of G. kola seeds for 56 days and a significant difference (\(p<0.05\)) was observed in fecundity. The egg's diameter was improved with the dose of ethanol extract in the fish diet, which is in agreement with our results. The increased fecundity of fed fish with herbal supplemented diet was due to the presence of bioflavonoids and xanthone in this plant [48]. The combinations are powerful antioxidants and can increase estrogen production, thereby leading to egg production and maturation. [PERSON] et al. (2009) [11] assessed that Genesis (G, a commercial mixture of phytoestrogens) including phytostrogens, which increased growth rate and sex separation in the Sharptooth catfish _Clarias gariepinus_. They concluded that the usage of higher doses and treatment durations of Genesis could be more effective for all-female production of the Sharptooth catfish. Moreover, phytoestrogens were able to motivate vitellogenin synthesis in Siberian sturgeon _Acipenser baeri_[49] and common carp, _Cypirinus carpio_[50]. Thus, it seems that phytoestrogens could effectively be used as natural alternatives to synthetic hormones for sex reversal in fish culture.