Can big cats be polydactyl? The answer is probably, yes. Although, having read a lot about the big cats and all wild cat species and seen many photographs, I have not seen one polydactyl paw on any wild cat of any size or description. That does not mean that they don’t exist.
The only question that I have is whether the mutation which causes cats to be polydactyl is confined to domestic cats because of their evolution over about 10,000 years of domestication. I would doubt that this dominant mutated gene is confined to domestic cats and therefore I have to presume that it exists among wild cats in the wild.
A responder on the Quora.com website writes that polydactylism has been seen in lions and ‘panthers’ and other creatures outside the feline family. I can believe it but she does not present any hard evidence. And there is no reference to this well-known congenital condition being present in wild cat species in the best books that I have. Neither can I find, on a rather quick search online, a reference to this. All the references are in relation to domestic cats. Indeed it is only in reference to domestic cats that we read about polydactylism. If a visitor can point to a reference I’d be very grateful and will amend the page accordingly.
As mentioned, the lack of a reference online or in books is not conclusive as to the existence or otherwise of polydactylism in big cats. It’s simply creates a question mark in my mind. Sadly, there is no clean answer but logic dictates that it does exist amongst the big cats although perhaps very rarely.