Because of their small numbers, rare breeds may have a threatened conservation status, and they may be protected under regional laws.
Breeds may be defined as a group of animals that share visible characteristics, such as Pinto horses, which are all spotted.
TLC places a livestock breed under "critical" status when it has "fewer than 200 annual registrations in the United States and estimated global population less than 2,000".
In postwar Britain, for example, the introduction of the Poland China pig and the Texel sheep affected populations of historic breeds, which were seen as less profitable for farmers.
[16] In 2009, The Livestock Conservancy launched an online classified advertising service for promoting rare breeds.