Ah yeah the Siberian fox experiment is interesting. They found that the tamer foxes had a tendency towards neoteny, ie. basically retaining juvenile features and slower development, and they even lost some of their intelligence too which was interesting. The same has happened with dogs, physically they're closer to juvenile wolves and generally they're also less intelligent than wolves.
Didn't know someone had tried the same with panthers and cheetahs though, that's pretty surprising. Sounds like a bit of a project to tame panthers of all creatures when even housecats aren't as domesticated as eg. dogs