The extraordinary scene was captured by photography student Casey Gutteridge at the Santago Rare Leopard Project in Hertfordshire. The 19-year-old, from Potters Bar, Hertfordshire, who was photographing the leopard for a course project, was astounded by the mouse's behaviour. He said: 'I have no idea where the mouse came from - he just appeared in the enclosure after the keeper had dropped in the meat for the leopard. 'He didn't take any notice of the leopard, just went straight over to the meat and started feeding himself. 'But the leopard was pretty surprised - she bent down and sniffed the mouse and flinched a bit like she was scared. 'In the meantime the mouse just carried on eating like nothing had happened.