If you compare the nasal bone structure of brachycephalic dog breeds from 50 years to the same breed now, the change is drastic. (wagwalking.com)
Excessively large palpebral fissures is common in brachycephalic dog breeds with congenital exophthalmos (shallow orbits), the Bloodhound, St. Bernard, American and English Cocker spaniel. (lowchensaustralia.com)
This is linked to a common health condition in brachycephalic dogs called «Brachycephalic Airway Obstruction Syndrome (BAOS).» (thehappypuppysite.com)