David Thompson 
Encyclopaedia of Animal Breeding Methods and Techniques (Dairy and Farm Animal Breeding) 

Animals with homogeneous appearance, behaviour and other characteristics grew known as particular breeds and they are bred through culling particular traits and selecting for others. Purebred animals have a single recognizable breed and purebreds with recorded lineage are called pedigreed. Crossbreeds are a mix of two purebreds, whereas mixed breeds are a mix of several breeds, often unknown. Animal breeding begins with breeding stock, a group of animals used for the purpose of planned breeding. When individuals are looking to breed animals, they look for certain valuable traits in purebred stock for a certain purpose, or may intend to use some type of crossbreeding to produce a new type of stock with different and superior abilities. lt is hoped that this encyclopaedia will not only meet the requirements of students but will also be useful as a guide to the academic professionals.