While we humans need minimum of 6-8 hours of sleep and most of the time have trouble even with that, there are some animals that spend around 80% of their day sleeping.
Cat, the cute and fluffy pet, spends 12 hours in its own dreamland. Also mammals like bats and giant armadillos spend 18 precious hours in snoozing.
Other mammals that require 10 or more hours of sleep are Dogs, House Mouse, Lion and few more. Some animals share a similar sleeping pattern like humans and they are Polar Bear, Bottle-nosed Dolphins, Pigs. There are also some animals like Horse, Cow, Giraffe, Elephant that for ample rest take less than 10 hours of sleep.