What is the average litter size for zebras?

Answer 1

just one. it's rare to have two though. Zebras are just like horses.
usually 1

but sometimes twins but it is quite rare.

typically 1 but it can have twins and the most ever known is 3 at once

A zebra has one foal per birth, it is extremely rare to have twins. If it does have twins, they very very very rarely survive.

Answer 2

A zebra often will have only one foal per year, rarely two per year.

Answer 3

female zebras nearly always only have one foal

Answer 4

One foal per mare, just like in horses.

Answer 5

1 sometimes more