Question

why are some animals called the Beast of Burden "?

Answer 1

Any animal that helps carry heavy loads like mules, llamas, donkeys are called the burden animals.

Any kind of domesticated animals that are trained in doing tasks for the humans are also referred to as the burden animals.

These animals are really helpful for the people to carry load from one place to another.

Answer 2

donkey ,lalma, mules are the answer