The ailing crocodile had been off its food for a week before Kaohsiung zoo sent in its vet to take a look.

Chang Poiyu could hardly have guessed then that the 600lb (270kg) reptile would choose that very moment to get peckish. As he leant through the bars of the animal’s enclosure to remove a tranquilliser dart from its thick hide, the crocodile suddenly came to and turned on Mr Chang, biting off his left arm just below the elbow. Yesterday the unfortunate vet was recovering in hospital after a seven-hour operation to reattach the severed limb, which had been retrieved from the enclosure by colleagues. Doctors hailed the surgery as successful but said that it could take up to two weeks to tell whether all the arm’s functions would be restored.

It seemed like a shocking act of ingratitude on the part of the croc because the vet is famed for his devotion to his charges. Mr Chang once jumped into a lion’s cage to lead it to safety after the zoo was deluged by floodwaters.

Another time, Taiwanese television cameras caught him weeping at the unexpected death of a beloved elephant. On Wednesday the zoo had called him to the reptile enclosure after growing concern that the Nile crocodile, the male of a mating pair, had gone off its food.

Mr Chang fired a tranquilliser dart through the bars of the enclosure to examine the crocodile more closely but when he leant through to remove it from the scaly hide, the reptile opened its eyes suddenly and snapped.

Zoo workers watched in horror as the crocodile wrenched off Mr Chang’s forearm two inches below the elbow. “The crocodile was in a fast move, it bit off the arm and swung twice,” one witness said.

A colleague wrapped a tourniquet around the stump and whisked Mr Chang to hospital, thinking that his arm was lost. But at that moment the crocodile’s appetite seemed to wane again. He stood in the enclosure, holding the arm in his jaw, as TV crews and photographers descended on the zoo to record the grisly spectacle.

Another guard, Chang Fuyi, summoned an armed police officer who was on duty at the zoo. “A thought crossed my mind before I shot, ‘If I cannot kill the crocodile, at least I want to scare it to spit out the arm’,” he said. The officer fired two shots at the crocodile’s neck and it spat out the arm.

Another guard then managed to retrieve the arm, which was rushed in a refrigerator to the Chungho Memorial Hospital, arriving 80 minutes after the unconscious Mr Chang.

Yesterday, after eight hours of surgery, Mr Chang was filmed for television, smiling and waving from his hospital bed with his healthy arm.

Mr Chang’s assailant, meanwhile, escaped unhurt. “The crocodile was unharmed as we didn’t find any bullet holes on its hide,” Chen Potsun, a zoo official, said. “It probably was shocked and opened its mouth to let go of the limb.”

It has already become something of a celebrity at the zoo, with hundreds of visitors flocking to see it, even daring to cross a police line for a closer glimpse. The crocodile came to the zoo ten years ago, after it was bought from a local resident who had kept it as a pet — perhaps unwisely, given the Nile crocodile’s reputation as a man-eater.

Friends of Mr Chang said that he was almost certain to return to work at the zoo, but expressed concerns over whether he would still be able to pursue his second love — playing the piano.

To the rescue

How to save a severed limb:

1: Wrap the severed limb in clingfilm or put it in a polythene bag

2: Wrap this again in something soft such as a tea towel. Then place in another plastic bag, filled with crushed ice.

3: Note time of the injury and casualty’s name and label the bag

4: Artery forceps are applied to stem bleeding and pad and bandage pressure dressing is used against the wound to control haemorrhage

5: Chances of survival for extremities and digits is 70-80 per cent. If the severed limb can be salvaged, surgeons will carry out limb replantation surgery where it is attached back to the body. If the limb is dead only a prosthetic can be attached

Source: www.pocketdoctor.co.uk ; orthopaedic websites

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