This "song"—which I suspect is actually a cante-fable—seems to be found in two books:

Coyote Wisdom by J. Frank Dobie, (Texas Folklore Society, 1938), page 254.

A Treasury of Southern Folklore by B. A. Botkin (Crown Publishers, 1949), page 518.

Neither of those is completely viewable online, but Google shows this much:

Here, Sambo! And Ringo!
Your master's almost gone!
And a poo-pam and a poo,
And a poo-pam and a po-o-o!

This time the dogs barely heard him. They looked at the fence. ...