Answer:
What goes zub zub zub
It has plenty of backbone but doesn't have a let. It peels like an orange but it comes from an egg.
Looks like a hippo crossed with a unicorn.
This noble creature has the embarrassing inability to get up once it's been flipped onto its back.
It can be white or blue or black, Humped or have a horn. And when it talks it sings its menuets, as it's travelling the depths.
Black we are and much admired. Many seek us if they are tired. We tire the horse, and comfort man, and turn White when we've fulfilled your plan.