a huge 29-stone silverback gorilla suffering from severe tooth pain. The South African zoo's chief breeding primate, Binga, exhibited signs of distress by ceasing to eat and appeared visibly upset.

Gorillas are the biggest of all primates. Male gorillas, called silverbacks because of the silver hair on their backs, can weigh up to 200 kilograms (440 pounds) and stand over 1.8 metres (6 feet) ...