Animal biotechnology

Abstract

Biotechnology has taken two directions in efforts to speed up animal production above the rates achievable by selective breeding. Recombinant DNA methods have been used to engineer protein gene products for direct administration to livestock, as in recombinant growth hormone to stimulate lactation in dairy cows or yield fastergrowing, leaner carcasses in meat animals. Cloned cellulolytic genes have been inserted into ruminal microorganisms with a view to improving ruminant nutrition. The other direction is to use advanced breeding technologies to enhance performance. These include laboratory culture of large numbers of viable embryos for nonsurgical transfer to surrogate mothers, development of methods for sexing sperm and embryos, cloning embryos by nuclear transplantation and gene transfer to create livestock with superior performance traits. In all cases material progress will depend upon a deeper understanding of the underlying physiological and developmental control mechanisms and public confidence that due regard is being paid to animal welfare, and to social and environmental implications.