An African pancake tortoise is recovering after an operation to remove a bladder stone the size of a small egg which could have killed her.

A team of expert veterinarians at Bristol Zoo performed an hour-long operation on Polly, the pancake tortoise, after discovering the bladder stone during a routine health check-up.

During the procedure, vets had to cut away a hole in the bottom of Polly's shell to remove the stone.

The bladder stone weighed 19g and measured 3.7cm (1.5ins) by 3cm (1.2s) while Polly herself measures just 14cm (5.5 inches) long from head to tail.

The five-year-old tortoise is now bandaged up and recovering well in the zoo's reptile house, but will be off-show to visitors until she has fully recovered from her operation.

Sharon Redrobe, head of veterinary services, said: "We x-rayed the tortoise as part of a standard health check, and were amazed when we saw the size of the bladder stone.

"Anaesthetising a tortoise is quite tricky and requires specialist training, but she is likely to have been in some discomfort so we took the decision to remove the stone as soon as possible.

"I've performed bladder stone operations on tortoises before, but never on a pancake tortoise and never with a bladder stone this big.

African pancake tortoises are classed as a vulnerable species by the International Union for Conservation of Nature and Natural Resources (IUCN), which mean they are at high risk of facing extinction. in the wild in future.

Bristol Zoo co-manages a breeding programme for the species.

For more local days out news, click here