I think most of us realise that white cats are more susceptible to their ears being badly sunburned which can result in cancer and in turn result in the ears being amputated. Incidentally, a cat’s ears are also very susceptible to being lost due to frostbite.
The question is why are white cats more susceptible? Someone may wish to correct me but white cats are white because the fur lacks pigmentation. It is not that the fur has white pigmentation. Pigmentation blocks the ultraviolet light which damages the skin. Without pigmentation more light is able to impinge upon the cat’s skin. In addition, we know that the fur on the air flap of the cat is very thin, almost non-existent towards the tip.
The same level of very thin fur also exists on cats of different coat colours and it therefore makes you wonder why those cats don’t also get sunburnt ears. Perhaps they do but less so.
A counter argument might be that white fur should be more likely to reflect light. But it seems that the ‘transparency’ of white fur is the major influence.
Anyway, white cats are susceptible because their fur lacks pigmentation. This leads to the next thought which is why don’t domestic cats take evasive action when lying in the sun for a long time resulting in their ears becoming badly sunburned?
We know that the wildcat ancestor to the domestic cat is the North African wildcat. This cat does not get sunburnt. They are built for the conditions in which they live. However, the domestic cat clearly has lost his ability to live under certain conditions such as hot sun which is ironic because those are exactly the sort of environmental conditions under which the North African wildcat lived.
In addition, the domestic cat appears to have lost his ability to detect when the environmental conditions are detrimental to his health. Both of these aspects of the domestic cat indicates to me that he has lost some natural instincts through domestication. Perhaps the situation is that the wildcat was never under direct threat from the environmental conditions and therefore there is no inherent self-training through evolution which alerts the domestic cat to the dangers of being so badly sunburned that the injury threatens his life.
The Clinical Veterinary Officer of Cats Protection in the UK said:
“We regularly see cats in our care with badly sunburned ears which need to be amputated to prevent the development or spread of cancer… Cats are notorious for their love of lounging around in the sun but, just as with humans, this can be a very dangerous activity when the sun is at its hottest. White cats, or those with unpigmented white noses or ears, are at the greatest risk.”
People who care for white cats should ensure there cats are inside when the sun is hot.