The Stewards of The Jockey Club have approved changes to clarify the eligibility for registration of foals resulting from certain breeding practices. The longstanding rule permits registration and listing in The American Stud Book of only those foals that have been bred by natural means."The revision makes clear that natural breeding practices do not include cloning," said Edward "Buddy" Bishop, registrar of The Jockey Club.Section V, Rule 1D, which goes into effect immediately, now states "To be eligible for registration, a foal must be the result of a stallion's natural service with a broodmare (which is the physical mounting of a broodmare by a stallion), and a natural gestation must take place in, and delivery must be from, the body of the same broodmare in which the foal was conceived."For example, and without limiting the above, any foal resulting from or produced by the processes of Artificial Insemination, Embryo Transfer, Cloning or any other form of genetic manipulation not specified, shall not be eligible for registration. As an aid to the natural service, a portion of the ejaculate produced by the stallion during such cover may immediately be placed in the uterus of the broodmare bred.The Principal Rules and Requirements of The American Stud Book defines cloning as: "Any method by which the genetic material of an unfertilized egg or an embryo is removed, replaced by genetic material taken from another organism, added to with genetic material from another organism, or otherwise modified by any means in order to produce a live foal." The Jockey Club's rules governing registration mirror those followed by the more than 50 recognized Thoroughbred stud books worldwide under the International Federation of Horseracing Authorities' "International Agreement on Breeding and Racing," to which The Jockey Club is a signatory.