Commercial aspects of cloning and genetic modification in cattle

A range of potential commercial applications of cloning and genetic modification in cattle has been suggested over the last decade. It includes the rapid multiplication of elite genotypes, production of valuable human proteins, altered production characteristics, increased disease resistance and milk with improved nutritional value and processing capabilities. However, an economic return from the sale of product is far from reality in any of these areas. One impediment to achieving economic sustainability is the extremely low efficiency in producing healthy offspring from transferred cloned embryos. Other significant impediments are societal concerns surrounding such technologies, animal welfare issues and regulatory requirements. This review will focus on current biological limitations and technical capabilities in commercial settings, the changes required to allow the production and sale of products at economically sustainable levels, cryopreservation and the progress towards automation of cloning techniques.