These may be a reach, but they do make reference to horses - "Love Minus Zero" (Bob Dylan) "That Song About The Midway" (Joni Mitchell) "Bonny Light Horseman" (Eliza Carthy & Nancy Kerr) There's also the famous Stephen Foster song "Camptown Races" - and a little tune from the early 60s that starts out "A horse is a horse, of course, of course ...".