Dog on an airplane

I'm going on an airplane soon, with my tiny 6 pound dog. He has anxiety, and I've been testing different ways to reduce it, like having him spend lots of time in his carrier before the flight, so he can get used to it.

I know he is not allowed to be out of his carrier during the flight, but does anyone know if he's allowed to have a bone in his carrier to crunch on? I've gotten mixed reviews about it, and during TSA the bone would not be in his carrier, only afterwards.

I am wondering what strategies other people use for their dogs, to help alleviate some of the anxiety during a flight.