Any cat parents notice rusting fur in feline hyperaesthesia syndrome cats?

I know feline hyperaesthesia syndrome (FHS) is one of those things no one knows exactly what causes it. Yesterday I was reading about black fur turning red ("rusting"), and one of the causes is not enough dietary tyrosine / phenylalanine (phenylalanine can get transformed into tyrosine). Cats require more tyrosine for melanin production (so making fur black) than they need for general growth. I read further and found out that another thing low tyrosine is related to is neuropathy.

So my question:

Has anyone noticed if their black cats with FHS have fur that is also turning red? I'm especially curious about indoor cats, since sitting in the sun can also cause rusting. If FHS is a nerve thing, maybe there's some relationship with a deficiency that can also cause nerve issues...

Hello Samus,

I have a total black haired male cat named Porthos.  I also have his brother d'Artagnan who is black & white.  My Porthos sucks his paws since he's a baby.  Actually, he used to suck his thumb, since he's polydactyl.

Narlia was born black and white bits but ive noticed she has brown fur and like.strips in the fur but the other kittens in her litter were tabbies could this have some thing to do with her fur changing and laying in the sun x

What cute kitties! d'Artagnan looks like my cat, except with more white on his nose.

I wouldn't worry too much about your cat's paw sucking. My cat has a similar light spot from sucking on herself. She has one spot she sucks on when she's happy. You know how most cats will do that thing where they knead the air when they're really cozy. She does that plus suck on herself. I think the spot is from whatever's in her spit staining her fur. If it were a general deficiency in something it'd be all over.

If he's chewing on his paw, that's another story. That is often a sign of allergy to something, and maybe when you said he sucks on his paw that's what the vet pictured.

The back twitching does sound like FHS, but it's one of those things that's like, well my cat does weird stuff and no one knows why. I only found out about FHS recently and I think my cat (now 13) has had it her entire life. She reallllly doesn't like long full body pets, especially near the end of her back. She has similar back twitchy stuff when touched there, sometimes worse than other times. (Ewwwww she just totally burped in my face!!) So I just stick to scratching her head and she's happy. She IS allergic to some foods, but I don't know if that's related at all.

And Paula Jane I think a lot of black cats are secretly tabbies and you don't find out until they go out in the sun. So sneaky!!

Thank you for your reply . Yes i thought that too . Yes very sneaky lol [emoji]128568[/emoji][emoji]128568[/emoji][emoji]128569[/emoji][emoji]128569[/emoji][emoji]128569[/emoji]