Vets in Thailand have removed the world’s largest-ever gallstone from an elephant – only the second time that such a procedure has been performed. Medics started work on Sai Thong, 50, after she lost her appetite, was struggling to go to the toilet and then collapsed with severe stomachache at an elephant camp in Pattaya, eastern Thailand. Veterinarians from Bangkok’s Kasetsart University visited the three-tonne jumbo to check on her health. At first, they thought the condition was only due to old age. However, the medics were shocked when they performed an endoscopy in nearby Kamphaeng Phet province on March 30 and found a 20cm by 15cm stone inside her gallbladder. The vets operated on the jumbo the same day by tying her on a harness attached to a crane used on building sites to keep her upright and prevent her from falling over during the procedure, when general anesthetics were given. After six hours, the team of more than 20 vets were able to extract the huge 1.7kg stone from her gallbladder. Associate Professor Dr Nikorn Thongthip, part of the veterinary team that operated on Sai Thong, said it was only the second time in the world that a gallstone had been removed from an elephant. He said the operation was a breakthrough for the international veterinary community and said many institutes had asked the faculty to share the knowledge on treating large animals. The doctor added: ‘This is only the second case in the world of a gallstone being removed from an elephant. The first time, we performed similar surgery on Kham Moon, a 45-year-old male elephant. ‘However, the case of Sai Thong is different, as we removed one big gallstone weighing 1.7kg. In the case of Kham Moon, we removed over 162 small gallstones weighing a total of 8kg.’ Aside from the stone mass, Sai Thong’s urethra had also been infected following weeks of having difficulty urinating. Medics said that Sai Thong almost had an acute kidney failure due to the massive blockage in her bladder and needed blood transfusions following the operation. He said: ‘I am relieved that we were able to treat her before the infection became acute. The operation was successful thanks to everyone’s efforts.’ Elephants are the national animal of Thailand. An estimated 2,000 elephants are living in the wild and a similar number in captivity where they live in sanctuaries, zoos or work privately for hire at weddings and festivals.