What is wrong with my dog?

[Sleepy]

First of all, I have a mutt dog, so any common respiratory problems a certain pure bred dog would experience, this is not the case. He is a healthy 2 year old dog (guessing of lab/shephard/something mix). Only problem is when he lays flat on his back, he sneezes. I'm not very experienced with dogs and this seems really odd to me. Anyone have any idea what can be causing this?

 

[ElizK]

I don't think anything in wrong. My cocker/beagle mix does it too. I don't think it's anything to worry about.

 

[DisneyBride94]

My Shelties all seemed to sneeze when they were pleased about something...

 

[Sleepy]

My Shelties all seemed to sneeze when they were pleased about something...

Considering my dog once lived on the street, dealt with people yelling and throwing rocks at him and he ate nothing but cooked pasta that the neighbor lady was nice enough to feed him.....he has alot to be pleased about. His fav is to have his chest scratched, so he flips over alot. That is when the sneezing begins.