As far as the pressure is concerned, I'm thinking that there must be some effect on the animal's physiology, particularly the sensory systems. The ordeal of shipping in pressurized cargo can't be good. Anyone who's travelled by air knows how variable the cabin pressure can be.
I used to do a lot of mountain travel and always paid close attention to my altimeter/barometer to navigate and predict weather change. Too great a shift in density/altitude can have catastrophic effects on mammalian cardiopulmonary systems. This is what started me wondering if there was a reptilian equivalent.
Revenge is a dish best served cold...
With a side plate of steaming entrails,
And a nice Bordeaux!