From international cat care. Further Evidence On The Suffering Of Flat-Faced Cats. "Those with flat faces and short noses are termed brachycephalic (the same term is used for dogs such as bulldogs and pugs), and the breeds most affected are Persians and Exotic Shorthairs. Sadly, this flat-faced look is directly linked to a number of health issues... "
We have created cats that cannot breathe normally, and have reduced breathing capacity (pinch your nose slightly to feel what this is like), that can’t run, jump and climb (important behaviors for cats) without distress, that often have protruding eyes that can become damaged and painful, skin that can get infected, and that can’t even eat without difficulty. This is what we must not lose sight of. A cat’s health and welfare must come before its looks. "
Page one Research. " the jawbones of those with extreme brachycephaly were clearly misaligned, the cats had no visible part of the skull for the jaw muscles to attach to, some had a protruding lower jaw, and some also showed teeth abnormalities, all of which may lead to eating difficulties. Other deformities included ‘osseous defects’ – the holes in the skull... "
"the space inside the braincase was reduced, leading to compression of the brain. A third of these Persians had clear signs of internal hydrocephalus – a build-up of fluid inside the brain. This is associated with lots of problems in cats including seizures and blindness. In most of the extremely flat-faced Persians, the back of the brain was even protruding out of the base of the skull and into the spinal cord (this was also seen in some of the less extremely flat-faced Persians)
" In five extremely flat-faced kittens, brain compression was so severe that the back of the brain had been pushed out of the skull into the space in the spine where the spinal cord is. These kittens were unable to stand or walk properly, were not alert, had head tremors, uncontrolled eye movements and misaligned eyes, abnormal breathing patterns, and their owners reported sessions of long-lasting, aimless screaming. The kittens were put to sleep...