Breed History

Breeds have developed in countless different ways in places all over the world. Any attempt at trying to summarize such development is inherently limited. One approach is to examine the ways that animal agriculture in the Americas and Europe has been influenced by breeds. With only a few exceptions, such as Arabian, Barb, Holstein, or Merino, most agriculturally significant breeds have much more recent origin. Much of the current concept of breed originated in Great Britain a few hundred years ago. Breed societies were first developed there and the work of Robert Bakewell is recognized as the first truly organized attempt to improve livestock. Great Britain is the place of origin for many breeds (e.g., Hereford, Angus, Shorthorn, Ayrshire, Jersey, Dorset, Hampshire, Suffolk, Leicester, Berkshire, Large White, Tamworth, Thoroughbred). Such breeds were developed with attention paid to local production practices and, in several cases, with influence from breeders who wished to show their animals in competition with other breeders.

Numerous breeds were developed on the European continent (e.g., Brown Swiss, Simmental, Limousin, Charolais, Chianina, Maine-Anjou, Salers, Rambouillet, Landrace). The exact origin of some of these breeds is difficult to trace because they developed as local strains over a period of centuries. They became uniform in appearance due to limited initial gene pools and because breeders in a localized area desired some degree of uniformity. Several of the European beef cattle breeds have become important contributors to North American beef production in the last 50 years because they possessed characteristics that were not available in the British breeds that previously dominated North American beef production.

The early Spanish explorers brought their livestock to the Americas. The animals they left behind have created their own legacy. Collectively they are referred to as the Criollo breeds. The Texas Longhorn, Spanish goat, and Mustang horse are the primary North American examples. In addition, the San Clemente goat, the Florida Cracker cattle, the Gulf Coast Native sheep, and several South American cattle breeds (e.g., Blanco Orejinegro, Romosinuano) derive from remnants left by the Spanish explorers.

Numerous breeds have their origin in the United States. This includes several breeds of swine (e.g., Chester White, Duroc, Hampshire, Spot) that were developed from breeding stock brought from Great Britain to the United States during the last part of the 19th century and the early part of the 20th century. The Brahman breed was developed from Indian cattle of the Bos indicus type, primarily Guzerat, Nellore, and Gir, brought to the Western Hemisphere in the 19th century. Brahman cattle have also been the basis for several breeds developed to combine the adaptive advantages of the Bos indicus with beef production strengths derived from British or European breeds (e.g., Santa Gertrudis, Beefmaster, Brangus, Simbrah, Braford). Numerous breeds of sheep have also been developed in the United States (e.g., Columbia, Debouillet, Katahdin, Montadale, Polypay, Targhee).

In the last half of the 20th century, closer scientific and cultural ties with many other countries opened up opportunities for bringing breeds with unique characteristics to the North America from many parts of the world. The Finnish Landrace and the Booroola Merino sheep and several Chinese swine breeds, including the Meishan and Fengjing, were imported because of their high prolificacy. Several cattle breeds from Africa (e.g., Africander, Boran, N'Dama, Nguni, Tuli) have been imported because they are tropically adapted. Some of the African cattle breeds are of the Bos taurus type, while others are from a grouping referred to as the Sanga cattle, which had their foundations in crosses between Bos indicus and Bos taurus cattle several centuries ago.

These different approaches to development also lead to different situations regarding the genetic makeup of breeds. Breed societies encourage and facilitate genetic improvement. Genetic improvement goals tend to differ among different breeds, which leads to differences among breeds in average genetic merit. Additionally, breed societies, necessarily, hold to pedigree barriers in order to maintain breed purity. These barriers create limited population size. This, inevitably, leads to inbreeding, which also differs among breeds and contributes to levels of heterosis when breeds are crossed.

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