Submitted to: Reproduction of Domestic Animals
Publication Type: Review Article
Publication Acceptance Date: 2/1/2008
Publication Date: 7/1/2008
Citation: Long, J.A. 2008. Reproductive Biotechnology and Gene Mapping: Tools for Conserving Rare Breeds of Livestock. Reproduction of Domestic Animals. 43 Suppl 2:83-8. Interpretive Summary: Today’s livestock diversity originated from the wild ancestor species and was subsequently shaped through the processes of mutation, genetic drift, and natural and human selection. Only a subset of the diversity present in the ancestral species survived in the domestic counterparts. A 2007 report released by UN Food and Agriculture Organization, "The State of the World's Animal Genetic Resources", compiled from surveys conducted in 169 countries, found that nearly 70 percent of the world's remaining livestock breeds are found in developing countries. The UN report was presented to more than 300 policy makers, scientists, breeders, and livestock keepers at the First International Technical Conference on Animal Genetic Resources, held in September 2007 in Interlaken, Switzerland. The conference aims were to adopt a global plan of action for conserving animal genetic resources as its main outcome. In this invited paper, the current and potential contributions of reproductive and molecular biotechnology are considered as tools for conserving rare breeds of livestock.
Technical Abstract: Approximately 40 livestock species, shaped by a long history of domestication and development, contribute to today’s agriculture and food production. During the past 100 years, however, there has been a net loss of diversity because of an increased rate of extinction of livestock breeds and varieties. The extinction of a breed or population means the loss of its unique adaptive attributes, which are under the control of many interacting genes and are the results of complex interactions between the genotype and the environment. Modern reproductive biotechnologies, such as artificial insemination, embryo transfer, in vitro fertilization, gamete/embryo micromanipulation, semen sexing, genome resource banking, and somatic cell nuclear transfer (cloning) have enormous potential for conserving rare breeds of livestock. In particular, the creation of genetic resource banks is key for the preservation and management of the remaining agricultural resources. Conserving remaining livestock breeds will be enabled by existing and emerging molecular biology technology. Gene mapping has been used to as a tool to understand livestock origin and diversity in several livestock species. As an alternative for the identification of genome regions carrying relevant genetic information (candidate gene approach), the concept of “population genomics” has been proposed, which utilizes phenotypic data at the breed level (or subpopulations within a breed), rather than at the individual level. Further, an extension of population genomics, termed “landscape genomics”, has great potential for aiding livestock conservation. Livestock by definition are adapted to the landscape (e.g. temperature, altitude, rainfall, disease challenge, nutritional challenge, and human selection). The aim of landscape genomics is to learn from the co-evolution of livestock and production systems and use the knowledge gained to better match different breeds with production circumstances.