ok, so this game is kina corny, but I'll name a horse breed that begins with A.
American saddlebred. Now I'll post a pic of it.
http://www.saddlebred-horses.com/images/terre1a.jpg
Next person has to name a breed that begins with a B and post a pic of IT. and so on and on. For Z, try and find a pic of a zorse or something like that.