This cover is based on page 1 of 'Canine Castaway', The Adventures of Rex the Wonder Dog (DC, 1952 series) #30 (November-December 1956)
Original printings of this series report it is from the Bell Syndicate Inc. Episodes were printed in A Date with Judy and Buzzy.
Subsequent US reprints of this story added a hyphen to retitle the story "The Super-Zoo from Krypton".
This reprint has had its original title removed and is possibly only part of the original feature.
This reprint appears to be extended to a full page with extra artwork and white space.