I have a huge kink for pretty much all aspects of tacking up, riding, and working horses. The fancier and more elaborate the tack, the better. A picture of a horse in a particularly beautiful saddle and bridle or elaborate driving harness can get me hard pretty easily. If I see a really nice saddle online in a catalogue I will get a chub just thinking about putting it on one of my horses. It's serious enough that I had to start avoiding horse shows and rodeos as a spectator (I could still compete though because my headspace is totally different when engaged in sport). Just the act of riding a horse by itself often makes me cum, without even doing anything intimate with them. And I am completely addicted to the scent of horse sweat (and pretty much all of their other scents as well). I've been known to lick the frothy sweat off my horses after a good workout. Going down on a hot sweaty mare after a good ride is sheer bliss. Another favorite of mine is riding them bareback to cool them down after a workout and letting my pants and underwear get totally saturated with their sweat as they dry off. Making out with horses is also a huge kink, I used to have a gelding that would literally shove his tongue into my mouth if I stood near him with my mouth open long enough (he was truly one in a million, I've never met another horse like him that was so hungry for sloppy kisses with tongue! I miss him terribly).
Also, any horse that loves to be ridden is a huge huge HUGE turnon (yes contrary to what some might have you believe there are horses out there who absolutely LOVE to work and you can tell pretty easily if you know how to speak their language). One of my horses that I can ride completely tackless will sometimes walk up to the fence standing parallel to it when he sees me coming and start pawing as he looks over his shoulder at me, getting increasingly agitated and even nickering until I relent and climb the fence to hop on his back. Makes me hard as diamonds every time that he's practically begging me to ride him. I've had others try to brush his behavior off as a conditioned response, but he doesn't do it every time he sees me, so there are definitely times he's not in the mood to be ridden. And I don't do anything to prompt it either, I can be doing something completely not involving him and he'll spot me and run over to the fence. Sometimes when I dismount he will give me a good nudge and stomp the ground as if to say "that's all?" One of my mares also loves it and will start nickering with anticipation when I saddle her up because she LOVES hitting the trails around my property with me. Mares presenting with their tail flagging and pussy winking are another big kink of mine.
I think it would be safe to say I'm a little more than obsessed with horses but I love it and wouldn't change a thing.