Husky dogs play on February 23, 2013 during an international dog sled race in Todtmoos, Germany. (Photo by Patrick Seeger/AFP Photo)

Musher Michael Ruopp of Germany starts with his sled dogs at the 23rd International Sled Dog Race in Oberhof, central Germany, Sunday, February 24, 2013. (Photo by Jens Meyer/AP Photo)

Musher Heidi Hiermeier of Germany competes with her sled dogs at the 23rd International Sled Dog Race in Oberhof, central Germany, Sunday, February 24, 2013. (Photo by Jens Meyer/AP Photo)

Husky dogs play on February 23, 2013 during an international dog sled race in Todtmoos, Germany. (Photo by Patrick Seeger/AFP Photo)

Eyes of a Husky dog are seen on February 23, 2013 during an international dog sled race in Todtmoos, Germany. (Photo by Patrick Seeger/AFP Photo)

A dog is pictured on February 23, 2013 during an international dog sled race in Todtmoos, Germany. (Photo by Patrick Seeger/AFP Photo)

A sled dog runs at the 23rd International Sled Dog Race in Oberhof, central Germany, Sunday, February 24, 2013. (Photo by Jens Meyer/AP Photo)

Sled dogs run at the 23rd International Sled Dog Race in Oberhof, central Germany, Sunday, February 24, 2013. (Photo by Jens Meyer/AP Photo)