The owner of that Basenji is a trainer at the zoo. They brought the B in to help the tiger cub develop some social skills and play ability because it was being raised independent of any other animals. If I remember correctly, the cub was going to be sent to another zoo with more tigers once it had grown up.
basenji.dk I'll 2nd that sight. Find the pictures and just settle down with a cup of tea. Some amazing action shots of Bs in action. Great photography.