I would ask the preowner what has been done as you would not want to give meds that are not needed. deworming them is a good thing to do, if they have not been. follow the directions though as you will have to repeat the deworming in a week or 10 days most times. but they should be in quarantine anyway at this time for a few weeks at least. while in there keep a check on them and their droppings as time goes by.. you may see some not so good droppings from stress of the move.When you get new pigeons, what meds should you give them?
I'm thinking that they should be wormed. Is there anything else that should be done as a preventative?