So I've been bored and I have an spare pet slot for the moment so I've been adopting pets from the pound with nice names, zapping them to something nice and then abandoning them.

Now I'm wondering if I should be doing this or not? Is there a limit to this sort of adopting and abandoning? I know I pay to adopt and pay to abandon, which I don't mind. I'm just worried about my rate of turn over, I've done 3 in about 3 days?

I don't think there's a limit. I think it's fine to zap pets you adopt (I do it myself). I think the thing that's frowned upon is endlessly making new pets. So adopting existing ones and zapping is fine. :)

I personally have done four in one day as you have described, I got a series of lucky zaps. So you can at least do that many. I know you can adopt more than that per day, because I did that a lot when the "own a pet of x color" Achievements came out. There probably isn't any limit except paying the fees to adopt/abandon.

Myself, when I take pets out of the Adopt R Us I also grant them a cheap minion (or a pricier one if I can think of one that would be escpecially fun for their name/color). I also take them to the Rathskeller Inn and check them in for max time. That way they are kept reaonably happy and fed for awhile, no matter if anyone else thinks they wan the color/species I zapped them into. The cost of doing this is way cheaper than the 10KsP abandon fee which I am already planning on paying, so I don't mind it.