What is this Reaction? (from airhorn)
 

The other day, I thought it would be funny to scare my mom with an air horn I had conveniently.
So I did. And it was hilarious. LOL

But when I blew the horn, Ozzy stopped, stood at attention, and started going nuts.
It was like he was excited, more than anything.

I sat there and would let air leak out of it (so it made a hissing sound) and he started going crazy. He was acting how he does at flyball.

I'll post a video when I can, but what might this reaction be?
Play? Excitement?
It wasn't fear - he jumped up on me and kinda looked like he wanted to take it from me, haha.

Sounds like excitement to me :)