When I was a kid we ended up with a great mouser named Rusty. He was a red tabby and had ten toes on the back, thirteen toes on the front. Almost all the polydactyl cats have mirrored feet (same number of toes on each front paw and the same for the back set). Rusty had his thirteenth toe stuck between where the thumb and index finger appear on a human hand, on the left paw.
Rusty was an astounding mouser, and we never had a problem with mice even though we lived at the top of a remote mountain in the Adirondacks. Any little creature that dared enter Rusty’s domain ended up as a cat snack. He woke the family several times with the crunching sounds of him eating half a mouse. He left the ass ends with the tail on the stairs, and they always reminded me of the tips of kosher dill pickles with a bit of stem still on the end.
Polydactyls do have problems with nail trimming. Even though we let Rusty roam about (no other cats in the area, so no kittens in the wild!), it never wore the nails down.Sometimes the extra toes grow nails faster, and holding down a 25-lb cat to trim nails is not a fun task. Rolling the cat in a bedsheet worked well.