Trainer Jimmy McConnell of Shelbyville, Tenn., rides champion walking horse Watch It Now before a 2009 football game in Knoxville, Tenn. Celebrations of the breed's distinctive gait are a 75-year-old tradition, but animal rights activists say that for many of those decades, the walking horse industry has abused animals to get their knees even higher. Wade Payne/AP hide caption

itoggle caption Wade Payne/AP

Chimpanzee Toni celebrated his 50th birthday at the Hellabrunn Zoo in Munich on Nov. 22, 2011. Sven Hoppe/DPA/Landov hide caption

itoggle caption Sven Hoppe/DPA/Landov

Michael Sharry visits with Bill, front, and Lou (now deceased) on Nov. 8, 2012, at Green Mountain College in Poultney, Vermont. Toby Talbot/AP hide caption

itoggle caption Toby Talbot/AP

After a leg injury didn't heal well earlier this year, Lou has difficulty walking. He and his partner, Bill, will be slaughtered at the end of the month, and their meat will be used to feed students at Green Mountain College in Vermont. Nina Keck/Vermont Public Radio hide caption

itoggle caption Nina Keck/Vermont Public Radio