When it came to Mr. Ed, I think Wilbur was actually the pet. Same with Francis and his human buddy, Donald O’Connor.
On The People’s Choice, Jackie Cooper had a basset hound named “Cleo”, whose thoughts (voiced by Mary Jane Croft), baleful observations of Sock’s dilemmas, are recorded on the soundtrack for the viewers’ amusement. The real name of the dog that played Cleo was “Bernadette”. Much of Cleo’s dialog consists of wisecracks. The popularity of the basset hound breed increased markedly with the run of the show. WIKI