Abstract
Modern animal breeding based on marker-assisted selection, genomic selection, artificial insemination, and embryo transfer have led to a significant improvement in the performance of domestic animals, and are the basis for a regular supply of high quality animal derived food. However, the current strategy of breeding animals over multiple generations to introduce novel traits is not realistic in responding to the unprecedented challenges faced by animal agriculture. The vast majority of arable land around the world is already under production, with land use being further restricted by urbanization, production of biofuels, and climate change. Production practices related to animal welfare such as castration and dehorning are often vilified and continue to influence public opinion. Finally, risks of global pandemics affecting animals, such as foot-and-mouth disease virus, or zoonotic diseases that affect both humans and animals alike (e.g., influenza) are One-Health challenges that need to be tackled. Addressing these pressing challenges requires next generation breeding technologies using genome editors such that permit replacement or transfer of alleles (genetic information) between individuals, lines, breeds, and even species. The animal science community envisions the genome editors, specifically CRISPR/Cas9 system, as essential tools for addressing livestock genetic engineering for agriculture, and One-Health challenges.