A randy tortoise which developed arthritis after bonking too much has been fitted with a pair of wheels to help him get around. Bert, a 22-year-old African spurred tortoise, now travels around with the help of heavy duty wheels strapped to his shell whenever his back left leg swells up. His keepers believe he is the largest tortoise in the world to have wheels fitted. Bert lives at the Secret Animal Garden at the Dinosaur Adventure Park in Norfolk. His keepers took the drastic move after they noticed severe swelling in his rear legs restricted his movement when he returned from a breeding programme in 2011. During his two month visit Bert, described as a "prolific breeder" by his keeper, had his way with up to five females producing an unknown number of offspring. But it appears the sweet-loving took its toll on the 100kg tortoise and vets later discovered that he had developed early onset arthritis on his return.