Booties. I'm not sure which kind those are, alot of times they are used to protect the hoof if the horse doesn't have shoes on, or to help prevent certain aliments that horses are prone to like tendon problems and what not. They're a pain in the butt to but on too!
Dude! I am already jealous that you live in Australia, get to see awesome places daily, and are a really good photographer...do you have to add one of my favorite type of animal into the equation? Amazing job as always. My Uncle would envy this shot.