No birds are left.
Moish – your example with the BigMac is worse (in Halacha) than the other example. A cheeseburger is an example of Milk and Meat that is prohibited by the Torah outright (because the meat and milk is cooked together). Having milk a half hour after meat, or even at the same meal if it is cold, is prohibited by the Rabbonon. Practically, it makes no difference (because both are prohibited), but it is good to know the difference.