According to Muppet Wiki, "Animal made his debut appearance in the 1975 pilot, The Muppet Show:
Sex and Violence where he was chained up in a basement cell when he wasn't onstage performing with the Electric Mayhem.
He later became a main character on The Muppet Show. He is a crazed drummer and speaks in a guttural shout, often repeating
a few simple phrases, such as "BEAT DRUMS! BEAT DRUMS!" or "WO-MAN!" In relatively calmer moods, he is capable
of more coherent conversation, but these instances were infrequent. His performer, Frank Oz said that he had his character
down to five words: sex, sleep, food, drums and pain."
Frank Oz (1975-1999)
Eric Jacobson (2002-present)
Kevin Clash (1996)
John Kennedy (2002-2003)
David Rudman (2004, puppetry only)
Drew Massey (2005)