“Usually wild hippos do not need to have their teeth cleaned,” said Pan Xiuwen, an official at the zoo in Shanghai.
“They usually eat grass, which is not likely to get stuck in the gaps between their teeth. However, at the zoo we feed them fruit and vegetables which can easily clog up their teeth,” he explained.
Shanghai Zoo decided to build a four foot-long tooth cleaner, after using a broom for years, to maintain the dental health of their hippopotamuses.
They are the third-largest land mammal in terms of weight, clocking up a hefty 1.5 to three-tonne mass and are widely considered to be one of the most aggressive and dangerous animals on the continent.
Despite their sluggish appearance, hippos are actually rather quick on their feet - they can outrun humans, running around 19 mph over short distances.
Hippopotamuses are semi-aquatic, herbivorous creatures, which usually inhabit rivers and lakes in sub-Saharan Africa.