question about panting

If my kitties start panting while playing should I stop right away?

I just got out their new feather toy that they go CRAZY over (it's just a wand with some feathers for them to chase--had to replace it recently as they destroyed the old one!) and they were panting very shortly after we started playing. I let them play a few minutes and then put it away. Now they're stretched out on the floor, pooped.

Good question!
I don't have an answer, but I've always stopped playing with my cats if/when they start panting.

My kitties play hard but don't pant. I would stop...let their heart rates go down, then start again.
Enjoy your wild kitties.
Lei

My kitty does that too with the laser pen ! I always stop for a bit until they've recovered.