Mama was shaved around Christmas after a rectal prolapse and hers is still growing in and it is very obvious where she was shaved still(and since they did her entire rear end and left half her tail she looks like she got a bad hair cut back there.) Attitude who was spayed 1 day before Mama has had her hair grow back in and it isn't noticeable. Both are Maine Coon mixes, even though Mama could possibly be full Maine Coon(she is Attitude's grandma) so they both have the long dense Maine Coon coats.
It just depends on the cat. Mama is an outside only cat(she let herself outside a week after getting out of the hospital, she had had enough of the inside, she is miserable inside so I let her stay outside) and it was really cold outside after her surgery and it only really started coming back in noticeably after it got warm out ironically enough. Attitude is inside only, she got out about 7-10 days after her surgery when it was snowing and when she came back in she was shivering and as I said hers grew back a lot faster even though she was inside only and Mama was outside only.