How do horses neigh

[Becky and Bassett]

I was having a discussion with friends about the anatomy of a horses mouth and how exactly they neighed. does it come from the larynx or vocal cords and air passing through the mouth. although cat see how this would work as horses cant breath through their mouths. Any ideas?
Thanks

 

[muddymate]

I don't know the physiological answer...but from observation they always have their nostrils flared when they neigh so presume the air enters that way and then something to do with the larynx?? Probably if you look up hobday operation or tie back you will find your answer in reverse as it were!