When Barney Fife presented his trusty new "bloodhound," Andy was not so impressed. "I don't believe that dog can find his own food dish," Sheriff Taylor remarked. "Thanks a LOT, Blue," Barney said to his not-so-crackerjack pooch.

Barney was being sarcastic. We wanted to offer our sincere thanks to ol' Blue. The canine character helped make one of the funniest episodes of The Andy Griffith Show (and more, as we'll get to in a bit). 

By the time the dog walked onto the set of "Barney's Bloodhound" in 1964, he was already a long-in-the-tooth animal actor. 

Pluto as Walter on 'Bonanza'

Perhaps you remember him on Hazel, in the 1961 episode "A Dog for Harold." Two years later, he was scampering about the Ponderosa as Walter the Dog on Bonanza, in the 1963 episode "A Friend of Walter's." That gave viewers a good luck as the dog's true colors — an orange-brown with gray ears.

Pluto as ''The Ugliest Dog in the World''

But 1965 was his true breakout year. The same shaggy dog turned up in Elly May's menagerie on The Beverly Hillbillies ("Dash Riprock, You Cad") and memorably wagged his way onto The Dick Van Dyke Show as "The Ugliest Dog in the World."

Pluto on 'The Beverly Hillbillies' (left) and 'Hazel' (right)

Yes, that joke was a little cruel. He's a cutie. Reportedly, the dog was part Otterhound. His real name was Pluto, and he was one of the many wonderful performers handled by legendary Hollywood animal trainer Frank Inn.

Inn was perhaps best known for Higgins, the tiny terrier mix who played "Dog" on Petticoat Junction and Benji. His cat, Orangey, was the most ubiquitous feline of 1960s, turning up in everything from Breakfast at Tiffany's to Mission: Impossible.

Pluto in ''A Man's Best Friend''

Pluto deserves equal acclaim. Certainly, The Andy Griffith Show adored him. In his hardest-working year, 1965, he returned to Mayberry, cuddling up to Goober in "A Man's Best Friend." Oh, and had also pawed his way into season two ("Jailbreak") and season three ("Dogs, Dogs, Dogs").

He was only Blue the one time. What other performers can claim to have portrayed four different prominent characters on Andy?