Animal genetic resources for food and agriculture of animal genetic resources includes diversity at species, breed and within-breed level. Known are currently 8,800 different breeds of birds and mammals within 38 species used for food and agriculture. The main animal species used for food and agriculture production are cattle, sheep, goats, chickens and pigs. In the livestock world, these species are often referred to as "the big five". Some less-utilized species include the dromedary, donkey, bactrian camel, buffalo, guinea pig, horse, rabbit, yak, goose, duck, ostrich,partridge, pheasant, pigeon, and turkey. The history of animal genetic resources begins about 12,000 to 14,000 years ago. The domestication of major
Shetland animal breeds which was also the ancestor of the Hebridean and North Ronaldsay sheep). Shetlands are classed as a landrace or "unimproved" breed. Although Shetlands are small and slow-growing compared to commercial breeds, they are hardy, thrifty, easy lambers, adaptable and long-lived. The Shetland breed has survived for centuries in difficult conditions and on a poor diet so they thrive in better conditions. Shetlands retain many of their primitive survival instincts so they are easier to care for than many modern breeds. Shetland was the last surviving locality for a type of domestic pig known as the "grice." Small in size yet