“…Fenestrations in the mediastinum have also been noted in dogs, horses, cats, and rabbits. 47 , 48 , 49 , 50 , 51 , 52 , 53 For example, in a study of induced pneumothorax in 22 of 24 dogs in which air was injected into one pleural space, these dogs quickly developed bilateral pneumothorax. 47 …”