I've had a cat for a month, but when I lived with my grandmother back in Puerto Rico we had up to 20-30 cats. The idea of spaying and neutering animals wasn't that big in Puerto Rico, so we never got around to getting them fixed. We had many litters and pretty much kept all of them, but they were outdoor/indoor cats.
Now she has about 20 at most and are now indoors (She has a big house and fenced int are in the backyard connected to the house) and she has joined the SPCA in
PR and is working on getting them all fixed.