Conserving domestic animal diversity among composite populations

The erosion of domestic animal diversity due to natural causes and creative human activity is of serious concern if current production levels are to be sustained and the changing demands of future markets are to be addressed. The application of quantitative genetic principles that have proven to be successful in the genetic improvement of livestock and poultry species has made it possible to combine endangered landrace, population or breed with one or more established breeds into multi-breed (composite) populations for specific objectives. The formation of composite populations does not directly increase the number of animals in breeds under threat of being endangered or extinct. However, the high productivity of the newly developed composite population not only promotes the conservation of the inherent potential in some rare breeds with considerable genetic merit but can ensure their utilization to satisfy varying husbandry practices, marketing forces and consumer preferences for future markets of animals and animal products. The higher reproductive rate and lower generation interval are performance traits of economical importance to breed formation in sheep and goats where a larger number of breeds are associated with some degree of risk and declining at rates that may reach critical levels in the near future. The Finnish Landrace sheep, outstanding in fecundity, first brought to attention in 1963 has since been imported by more than 40 countries and combined with breeds established in the country to form composite populations contributing towards substantial reduction in ewe costs per unit of lamb marketed. This is a typical example of conservation with utilization. In the past centuries, more than 443 composite breed populations of sheep have been developed in 68 countries. At the same time in goats, there are more than 80 composite breed populations in 37 countries. Finally, the enhanced production efficiencies in the newly developed composite population provide an opportunity for exploiting genetic diversity to the benefit of the livestock and poultry industries, and at the same time conserving the inherent potential of the foundation breeds. Crown Copyright © 2004 Published by Elsevier B.V. All rights reserved