This is a curious one. When I was actually at the zoo these cages struck me as being horrible dark holes, but they certainly don't come across that way in the photo. They look like perfectly serviceable cages, and they also look reasonably new. I think they just photographed better than they actually were.
On the map this area seemed to be labelled as Meerkats, but on my visit the cages held Rusty-spotted Cats, Fishing Cats, Small Indian Civets, Ring-tailed Lemurs, and a Dry-zone Giant Squirrel.