An animal developed by introducing the desired foreign gene is called a Transgenic animal. Transgenic animals can be produced by the following methods.
1. Microinjection of desired genes into pronucleus of the fertilized egg.
2. Retroviral infection of fertilised eggs at 4 to 8 celled stages.
3. Genetic alterations of embryonic stem cells [ESC] and their reintroduction into the blastocyst. Transgenic animals are useful in biological, biomedical and biotechnological researches especially in animal husbandary, dairy and pharmaceutical industries.
Note : Transgenic animals are used as bioreactors for mass production of drugs and proteins. It is called genefarming or molecular farming.
e.g. :
Organism Table .
