Until 2009 no other breed of cow has been allowed into Jersey since before the French Revolution.The Herd Book was established in 1866 to record pedigree and progeny; a 'foundation stock' was nominated and it is to these cattle that all Jerseys can trace their ancestry. All Jersey cattle are registered with the Breed Society in order to maintain the purity of the breed and to enable breeders to follow the progress of their animals. When a calf is registered it will be given its own herd book number and its name with the herd prefix. Some farmers maintain the cow family name over generations.
For over 100 years a system of tests was used to determine a cow's quality. Through registration and comparison of animals a selection of the best bloodlines was made, which has allowed farmers to improve certain characteristics and remove defects.
It was these steps and the herd book, which helped the breed to become the second most popular dairy cattle in the world, with the Jersey cow today being found in most countries around the world.
Until 2009 no other breed of cow has been allowed into Jersey since before the French Revolution.