I don't think you can ninoconker. I just tried with my hunter but you can't. Sorry

YOU CAN IF ITS A non-combananint PET lol or sell the area where it is :D

go to a vendor dummy

if you have already learnt it (non-combat pet, mount) you cannot sell or trade it anyway
whatsoever)

you can trade in your old mount for a new one but has to be the same type of mount you can
change the kind you get