Abstract: The present invention relates the function of Dickkopf 3 (Dkk3 ) in testis using shRNA mediated knock down model. Specifically, the present invention provides knock down model comprising reduction in Dkk3 activity. The knock down model of Dkk3 consisting of non human vertebrates which have, incorporated in their genome, shRNA construct targeting mammalian Dkk3 gene exhibits low testis weight, low sperm count and has low litter size. The knock down model displays disrupted seminiferous tubules and are subfertile. The present invention model has a role in sex determination as its interruption leads to sex reversal of XY gonads, converting males to females. Sex reversal role of Dkk3 knock down model can find its utility in agricultural applications. The present invention describes Dkk3 as a dual function protein which is associated with sex determination as well as is essential for the process of spermatogenesis.

Abstract: The present invention provides a novel method of generating knock down models by electroporation of shRNA construct into the testis. The present invention provides an ethically superior, non-surgical, user friendly rapid method for the generation of permanent lines of shRNA knock down non human vertebrates. This invention is ethically superior as it does not involve any loss of animal life and drastically minimizes the production time and use of animals. Current techniques for making knockout models are cumbersome, require trained personnel, costly infrastructure and require hundreds of eggs collected after killing several females. In contrast, this method neither involves any costly infrastructure nor requires trained personnel. The invention also relates to the quick incorporation of shRNA gene construct into the germline of a species so that shRNA is inheritable.