Unlike people, dogs and cats breathe with open mouth when overheated, because they can't sweat like humans. Snub-nosed dogs or cats have condensed facial structures which impacts their ability to breathe normally, and during air travel these features impairs their ability to cool themselves off and makes them vulnerable to heat stroke.
The Embargoed or Prohibited Breed List, provided by an airline, was developed to eliminate the risk of death of these breeds while being transported via cargo.
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