This is for trumpet players, how do you make the horse whinny noise?

Question:

This is for trumpet players, how do you make the horse whinny noise?

I've searched the web, and i haven't gotten any results

Best Answer - Chosen by Asker: I actually play french horn, but all brass instruments can do this.

Get your lips as tight as you can, put the valves about half way down, blow and shake the trumpet a little.

Just keep practicing that, and changing things a little (embouchre, depression of valves, etc.. untill you have the sound you want)