A126
No. Natural Attacks are handled completely differently from iterative attacks. Your primary natural attack is made at your normal attack bonus, and all secondary attacks are made at your normal attack bonus for that weapon, -5, no matter how many secondary natural attacks you have, but each one is made only once (although if you have multiple copies of a single one, you get one attack with each; thus, a lion can get 2 claw attacks because it has two claws). If you make iterative attacks with a weapon, all your natural attacks are secondary. However, see Rapidstrike and the Improved version thereof, in the Draconomicon under Monstrous Feats.
EDIT: Ninja'd, but I've got additional info