A Japanese dolphin is squealing with delight after receiving a prosthetic tail to replace one amputated due to a skin disease. Fuji's handlers at the Churaumi Aquarium in Japan's southern most island of Okinawa say the fake tail may have saved her life as she had put on dangerous amounts of weight from being inactive after she lost her tail. "Because she was not exercising enough (after her tail was amputated) she gained weight and from blood samples we took we realized that her cholesterol levels were too high. We then were afraid that this might trigger other diseases so we had to come up with something," handler Masaya Koami said. The tail was custom made for Fuji by a friend of the handler who works at Japan's leading tire company Bridgestone. The rubber prosthetic device is slightly smaller than the tail of a dolphin of Fuji's size. It is made of material used for Formula One race car tires and the black silicon rubber was reinforced with artificial bone made of carbon-fiber. Sponge rubber was used for parts that come directly in contact with Fuji's skin. Bridgestone said they spent at least 10 million yen (about $83,000) to develop and produce the fin. As for Fuji, the freedom that it brought her is priceless. After initially being frightened of it, the dolphin now leaps and swims with vigor.