Hi, I'm not sure if its okay to give any flea medications or any other medications after AI, I don't have any experience with this, but I wonder if it would be the same precautions as a woman taking certain medications after becoming pregnant, I'm not sure if these medications would be safe for the puppies, should she get pregnant. Have you asked your vet if this is safe and okay? Maybe someone who has experience with breeding their bullies would know the answer, and hopefully someone will come along soon to give you advice. I would ask your vet though, as he would know if it was safe or not.
We don't use the flea meds at all on ours, but I wouldn't use them on a bitch that is nursing pups. We do give our pregnant and nursing bitches Sentinel and have never had a problem.