Researchers studied 13 cloned sheep, four of which were replicas of Dolly, the world's first somatic cell cloned sheep  The researchers examined the cloned sheep's musculoskeletal, metabolic and blood pressure profiles  The cloned sheep had only mild osteoarthritis, and only one had moderate osteoarthritis, compared with the control group  They have no symptoms of metabolic disease, have normal blood pressure and are relatively healthy
The Age of the control group in the study was younger than that of the experimental group
 As a result, the researchers note, the cloning of animals aging process is normal