As any fan of P.G Wodehouse's Blandings Castle stories will tell you, the best way to summon a pig is to shout "Pig Hoooey!"
My cats come to Fitz Fitz Fitz Fitz Fitz, and bit bit bit, itty bitty bit. Kitty kitty works well too.
I was told by a biology teacher in high school that if you gave a cat a name with an s or z in it the cat would learn his or her name, and come to it. She gave us Solomon who did indeed know his name and come to it.
Mother called our cats with a special whistle, one high one low. One summer a mockingbird picked up the whistle, and drove our poor dumb floof cat crazy.