Llamas and trader llamas spit behavior changes when leashed or unleashed

I found out that when tied to a Llama, if you hit it once (or more) it's going to start spitting endlessly. Running away or untying the llama is going to stop it. Here's the video.

From video:

1. Llama will spit endlessly when hit and does not have to move
2. Llama appears to stop spitting when moved using the lead
3. Llama stops spitting when unleashed
4. Llama does not continue spitting if hit, unleashed, and releashed