How did rhino get its horn?

Java

Rhinos don't naturally lose their horns, but sometimes they knock them off by accident. This can happen if the rhino takes on something much harder than a natural target - like the inside of a transport crate.

The horn will come off at the base, and leave a large, oozing wound. It's probably quite painful, but not life threatening. The horn will grow back, but it'll take years before it's back to a normal size.

Some species(Javan/Indian) has a lot smaller horns than the African species.

The most common reason for a rhino to lose its horns is that humans either cut them off (which is hard to do) or they kill then for their horns.