The almost extreme properties of antibodies to recognize small specific structures on other molecules have made them an indispensable tool in laboratory in various applications such as research, diagnostic and therapy. Antibodies presently available for these purposes are mostly mammalian monoclonal or polyclonal antibodies. The production of these antibodies requires normally the use of laboratory animals. Nowadays, most classical chosen mammals for polyclonal and monoclonal antibodies are rabbits and mice, respectively. The procedure involves two steps, each of which causes distress to the animals: the immunization