Southdown sheep reach the grapes on the vines. Baby Doll breeders claim that their sheep are closer to the original English Southdown than are the commercial Southdown sheep being grown today. Mature weights for rams range from 190 to 230 lb (86-104 kg); ewes weigh from 130 to 180 lb (59-81 kg). From mature ewes, fleece weights are between 5.0 and 8.0 lb ((2.5 - 3.6 kg) with a yield of 40% to 55%. The fleeces are considered medium-wool type with a fiber diameter of 23.5 to 29.0 microns and a numerical count of 54 to 60. The staple length ranges from
Breed registry stud book is a stud book or breed registry that does not accept any outside blood. The registered animals and all subsequent offspring trace back to the foundation stock. This ensures that the animal is a purebred member of the breed. In horses, an example of a closed stud book is that of the Thoroughbred, with a stud book tracing to 1791. The American Kennel Club is an example of a kennel club with primarily closed books for dogs; it allows new breeds to develop under its Foundation Stock Service, but such dogs are not eligible for competition in AKC