Does a cat need sunlight?

[rocksolid]

OK, i guess i don’t really know the answer from a human point of view but i seem to remember something about sunlight being converted into vitamin d or something. I’d look it up but i’m doubtful that any cite i find will cover domestic animals so it’s over to you dopers.

Background - A guy came and put down a deposit on one of our kittens at the weekend. Apparently he lives in a nuclear bunker. Seriously.

Obviously *he * gets out from time to time but i’m guessing the kitten won’t. So, given that it was built to house half an army it would seem pretty big, lots of room for kitten to play, fair enough. But what about sunlight? Will never seeing the sun affect her in anyway?

[Zsofia]

Well, she’ll be missing out on two of what seems to be cat-life’s favorite activities - Lying In the Sunbeam and Watching the Birdfeeder. Medically I have no idea, but mine just enjoy the sun so much.

[badkittypriestess]

They use the sunlight to help make up the slight drop in body temperature that happens once they fall asleep. Some cats will change their sleep positions to follow the movement of the sun. Cats, although considered diurnal are in fact not because if you shut the curtains at home during the day, their eyes dilate to allow more ‘soft light’ in, because the normal ‘brash light’ of daytime hurts their eyes.
Vision is but one aspect of why they don’t ‘need’ direct sunlight.

Most cats need access to a garden but indoor cats, who do not benefit from the mental stimulation provided by the outside world, can become bored and stressed. This can lead to serious behavioural problems and destructiveness. Cat activity toys are available so your cat can amuse herself when you are absent. Both indoor and outdoor cats enjoy playtime so interact with your cat through play, and provide a scratching post so she can exercise her claws without shredding your sofa. Studies have shown that indoor cats who are allowed to sleep on their owner’s bed at night are happier and more confident cats.

[guizot]

@rocksolid

…i seem to remember something about sunlight being converted into vitamin d or something. I’d look it up but i’m doubtful that any cite i find will cover domestic animals so it’s over to you dopers.

I don’t know why you would think that you wouldn’t be able to find the info, but I’ve heard the same thing about sunlight helping cats create vitamin D…

(And I’d look it up myself, but I’m just as lazy as you.)

@rocksolid

Background - A guy came and put down a deposit on one of our kittens at the weekend. Apparently he lives in a nuclear bunker. Seriously.

I think the real issue here is why a guy who lives in a nuclear bunker wants a kitten. Look into it.

[Kimstu]

@guizot

I don’t know why you would think that you wouldn’t be able to find the info, but I’ve heard the same thing about sunlight helping cats create vitamin D…

(And I’d look it up myself, but I’m just as lazy as you.)

It wasn’t that hard; googling “sunshine vitamin D cats” I found:

Dogs and cats cannot synthesize vitamin D-3; in the wild they would obtain it by eating prey so it is added to all their complete commercial pet foods.

[picunurse]

Yes, cats need sunlight to synthesize vitamin D.

[quote]
Vitamin D is also known as ‘the sunshine vitamin.’ Ultraviolet radiation from the sun is important to convert Vitamin D precursors into the active D form. This conversion takes place in the outer skin layers.

[Q.E.D]

@picunurse

Yes, cats need sunlight to synthesize vitamin D.

Not according to this research paper, (Idiosyncratic nutrient requirements of cats appear to be diet-induced evolutionary adaptations (Morris 2002):

For most animals, vitamin D is a conditionally essential nutrient as normal exposure to sunlight negates a dietary requirement. While cats are covered with hair, which would impede u.v. light reaching the skin, the propensity for cats to lie in the sun and expose their ventral abdomens (which have less hair than the rest of the body) suggested that cats might synthesise vitamin D. Sheep synthesise vitamin D on exposed parts of the body, despite their heavy pelage. However, kittens, both shaved and unshaved, exposed to direct sunlight were found not to be able to synthesise vitamin D (Morris, 1999). Cat skin contains a low concentration of 7-dehydrocholesterol, the precursor for pre-vitamin D (How et al. 1994; Morris, 1999). However, when vitamin D-deficient kittens were exposed to u.v. light and given a diet containing an inhibitor of the enzyme 7-dehydrocholesterol-D7-reductase (which catalyses the conversion of 7-dehydrocholesterol to cholesterol), the concentration of 7-dehydrocholesterol in skin was greatly augmented. Also, the concentrations of 25-hydroxyvitamin D in the plasma of these kittens increased to normal levels, indicating synthesis of vitamin D. Similar kittens exposed to u.v. light without the inhibitor in their diet, maintained low levels of 7-dehydrocholesterol in skin and deficient plasma levels of 25-hydroxyvitamin D.

How do cats in the wild obtain their vitamin D if they are unable to undertake endogenous synthesis? The vitamin D requirement of growing kittens is similar to that of other animals (Morris et al. 1999). Analyses of the vitamin D concentration of potential prey of cats (rodents and birds) indicated that the prey could provide adequate amounts of the vitamin without the need for endogenous synthesis. The cat’s obligatory dietary requirement for vitamin D is an example where synthesis is prevented by the high activity of an enzyme that reduces the availability of the precursor substrate.

[Swallowed_My_Cellphone]

@picunurse

Yes, cats need sunlight to synthesize vitamin D.

Vitamin D is also known as ‘the sunshine vitamin.’ Ultraviolet radiation from the sun is important to convert Vitamin D precursors into the active D form. This conversion takes place in the outer skin layers.

That totally contradicts the previous cite. And I wonder… how the hell is Lenny supposed to convert sunlight to Vitamin D in the outer layers of skin, when other than his nose and toes, the dude is covered with the wooliest hair you’ve ever seen on such a beast?

Seriously, his coat is so dense that the only glimpse I’ve seen of his actuall skin is when he got shaved for surgery.

ETA: Whoa, when did this thread become two pages long? Could’ve sworn it was just one page only two seconds ago. ::sigh:: I need reading glasses.

[rocksolid]

Guys, the opening of my OP was a little tongue in cheek. I did a quick google search (i’m not really that lazy) and i didn’t feel anything i found or that anyone has linked to so far to be very conclusive, at any rate i have no idea if there are other considerations other than vitamin d. I appreciate the responses nonetheless but i’m still not sure about this. I guess not many cat owners live underground huh? Who’d have thought?

The link from **picunurse ** seems closest to the mark, however it uses the words sunlight is important. In this context is that the same as essential? Are there alternatives to sunlight? Are ‘natural light’ bulbs good enough?

**guizot ** - It’s ok dude. It’s a tourist attraction, the guy is the MD so i guess he lives on site.

**badkittypriestess ** - Don’t worry we always check our buyers out before we sell! Other than the sunlight bit this guy seems pretty cool. Lot’s of space to explore, like much much bigger than our house that’s for sure. And it seems like he stays at the bunker a lot away from his family so i think kitty will have plenty attention.

Edit - need to type faster! Just noticed new posts, now even more confused! I really don’t want to stop this guy getting his kitten but i ain’t going to let it go to a bad home. Help!

[Swallowed_My_Cellphone]

WTF? Okay, when I first replied to this thread, it was only one page. Then, I swear to the Flying Spaghetti Monster, it was two. Now it’s only one again. What the heck is happening with my browser?

[silenus]

@badkittypriestess

Studies have shown that indoor cats who are allowed to sleep on their owner’s bed at night are happier and more confident cats.

Frak. If this is true our two are nascent Napoleons.

[Bridget_Burke]

@rocksolid

Guys, the opening of my OP was a little tongue in cheek. I did a quick google search (i’m not really that lazy) and i didn’t feel anything i found or that anyone has linked to so far to be very conclusive, at any rate i have no idea if there are other considerations other than vitamin d. I appreciate the responses nonetheless but i’m still not sure about this. I guess not many cat owners live underground huh? Who’d have thought?

The link from **picunurse ** seems closest to the mark, however it uses the words sunlight is important. In this context is that the same as essential? Are there alternatives to sunlight? Are ‘natural light’ bulbs good enough?

**guizot ** - It’s ok dude. It’s a tourist attraction, the guy is the MD so i guess he lives on site.

**badkittypriestess ** - Don’t worry we always check our buyers out before we sell! Other than the sunlight bit this guy seems pretty cool. Lot’s of space to explore, like much much bigger than our house that’s for sure. And it seems like he stays at the bunker a lot away from his family so i think kitty will have plenty attention.

Edit - need to type faster! Just noticed new posts, now even more confused! I really don’t want to stop this guy getting his kitten but i ain’t going to let it go to a bad home. Help!

Suggest the guy get two kittens. Indoor cats live longer & healthier lives than outdoor cats–but they might get bored. Two will keep each other company, fight & chase each other around the bunker. (Sounds like a good place to play “hide & go seek”–cats love to disappear.)

And the guy can take a short trip without feeling guilty. Just leave out enough food, water & litter–they won’t be lonely. (Not to say that the cats won’t try to make him feel guilty.)

[vetbridge]

Cats do not need sunlight as long as they are fed a good commercial diet. In fact, some cats (particularly white cats) will develop squamous cell sarcomas of the aural pinnae if exposed to “excess” sunlight.

[daffyduck]

badkittypriestess, I would love to see more.

Cats, although considered diurnal are in fact not because if you shut the curtains at home during the day, their eyes dilate to allow more ‘soft light’ in, because the normal ‘brash light’ of daytime hurts their eyes.

Hmmm… I’m definitely diurnal yet my eyes do exactly the same thing, so I don’t see how eyes dilating in darkness says anything about being diurnal or not. If you’re saying that cats are crepuscular or nocturnal, that would have to be demonstrated by activity records, not by deduction.

Do you have a citation for your statement: “the normal ‘brash light’ of daytime hurts their eyes.” I’ve never seen any reason to believe that daytime sunlight is hurting my cat’s eyes.

Studies have shown that indoor cats who are allowed to sleep on their owner’s bed at night are happier and more confident cats.

I’d love to see the methodology for determining the happiness of a cat. Do you have a link for any of these studies? Sounds interesting.

[panache45]

My current cat is almost 19, in excellent health, and has never been interested in sunlight. All the other cats I’ve ever had were addicted to sunlight, and none of them lived this long.