Change of fur colour - overnight

[HLR]

Our cat is a male, 6 year old, silver tabby cat with a white face. He's an outdoor cat and has a diet of cat biscuits only. This morning a section of fur, approx. 2cm by 1cm, under his whiskers on the RHS of his face, has changed colour overnight from white to dark grey. I've taken him to the vets - they've taken his temperature, checked his blood, his whiskers are all still there, the inside of his mouth is normal, it's not swollen - all appears fine. I showed the vet a 'before' picture - they have never seen an incident like this before and can offer no explanation as to why this has happened. In himself, he appears fine although perhaps a little more nervous/ jumpy than usual.
Has anyone heard of this happening to another cat, or knows why this might have happened?
Thank you

[Lilith]

Hi and welcome

15 years ago I got to know a feral community in these streets and they were recognisable by a grey stain between their shoulderblades, from roosting beneath parked cars.

I'm wondering if your little guy has had an unfortunate (but mercifully harmless) encounter with a car while wandering, which might have resulted in this change of colour on his face, which might just be a stain from the underside of the car? It could account for his jumpiness.

Very glad to hear he's all in one piece, whatever happened

[bobbys girl]

Hello and welcome to CC.

I think Lilith is right. There are many things he may have come into contact with that would stain his fur.

We live in an area of peat bog. There is an old turf (dried peat blocks) store in the field next to us. Gracie (tabby and white) had a set-to with another cat in the shed. When she came in her coat was grey and stayed that way for some days. And don't get me started on Bob's adventures in the bog. He is black so the black peat-stain doesn't show until he lies on the bed. Then he dries grey.

[HLR]

Hi - thank you for taking the time to respond. It really doesn't look like a stain! The vet has examined the section very carefully and is sure that it's the fur that has changed colour, but is not due to staining. The patch of fur is a consistent colour from the top to the bottom of the fur, and it's the identical colour to the grey parts of the rest of his body. The whiskers that come from the patch of coloured fur have no signs of any staining to them and it would be very difficult to stain such a small patch of fur, with no signs of the colour on the surrounding (and more protruding) parts of his face, or his whiskers. He's still a little jumpy today - one (American I think) website that I found suggested that sometimes this can happen if a cat has had a shock - a little like a human going grey overnight!