Trainer Joe Cain, a mainstay on the Kentucky circuit, is battling amyotrophic lateral sclerosis (ALS), known as Lou Gehrig’s Disease. For years, Cain has operated out of his farm in the faraway town of Russell Springs in the south-central part of Kentucky, driving tens of thousands of miles each year to run his horses at Ellis Park, Turfway Park, and other tracks. Before the races on opening day, July 4, about 50 friends and colleagues hosted Cain in the Ellis track kitchen, giving him a warm reception and a plaque honoring his tenure in racing.