Sheep and goats were first domesticated around 8,000 BC, making them the first of the domesticated food animals. Sheep are extremely adaptable and found all over the world, particularly in arid areas that do not support other types of livestock. Because sheep are raised in various environments, specific breeds have been developed to meet the needs of the environment and people. More than 100 breeds have been recorded. Different production systems are used in various areas of the world. Extensive year-round grazing, with large flocks (>1,000 sheep) and minimal sheep handling, is the typical system of sheep management where the climate and area to graze allow. Systems in New Zealand, South Africa, and Australia, where forage is available throughout the year, are prime examples of this type of management. Confinement and intensive feeding during the winter months, with access to range land pasture for the rest of the year, is a common system of large sheep flocks in parts of Europe, the UK, the western USA, and other countries that have snow and inclement weather seasonally.
Intensively managed smaller flocks can be found around the world, with sheep kept for milking, natural colored wool, purebred breeding stock, sale of lambs for home freezer trade, and hobby flocks on small acreages. Small flocks of breeding stock or hobby and pet flocks are common in the more developed areas of the world, particularly the USA and Canada.
Shepherding small flocks of sheep and goats along roadsides and common grazing areas is a typical management system in the Middle East, Asia, and Mexico.