Methods for genetic modification in poultry

The positive practical results in poultry breeding due to investigations on transgenesis and their prospects are discussed. The method for obtaining transgenic chickens and quail by microinjection of foreign DNA into eggs are described. It is based on a surgical operation, providing the access to the eggs to conduct microinjection of DNA and the natural formation of tertiary egg shells in the bird's genital tract. The microinjection into eggs at different stage of their development is considered in more detail. The transgenic chickens with humane growth hormone gene, b-galactosidase gene and humane b-interferon gene, and the transgenic quails with bovine growth hormone gene were produced by this technique. The quails with introduced bovine growth hormone gene and their offspring generations are characterized by an increased average egg mass and the higher immune status. Transgenesis used to transfer a target gene between two poultry lines, if compared with common breeding technologies, takes at least 7 to 8 years less and is probably less expensive, because there is no need in backcrosses to remove the unnecessary genes transmitted in the course of natural sexual hybridization. Nowadays, the transgenesis is very similar to directed, but indeterminate mutation. A transgene chances to insert genome, and that is why a lot of initial transgenic individuals are needed to achieve an inherited transgenesis.