A plastinated blood system of a horses head is seen during an exhibition preview at the Walter Zoo in Gossau, October 4, 2012. "Koerperwelten der Tiere" (Body Worlds of Animals), an exhibition of polymer preserved animals of German anatomist Gunther von Hagens will be open to public from October 5, 2012 until January 13, 2013. REUTERS/Miro Kuzmanovic (SWITZERLAND - Tags: EDUCATION ENTERTAINMENT SOCIETY)