How long of ~UVI3 exposure per day is enough for sufficient vitamin D3 synthesis?

[ajs]

I've been curious about this after noticing my cham seemingly spending less time on his top basking branch (He has entered his teenage panther months)

I have heard at least a couple of the podcasts by Bill where he discusses the experiments of determining safe/effective UVI levels without dietary D3, finding that there doesn't seem to be a difference in effectiveness or health from UVI 3 to UVI 6 in his experience. But, it's also made clear that there isn't much known about the minimum UVI needed for D3 synthesis (obvious risky experiment to conduct).

So, I would doubt that there is much out there on the minimum length of time per day of UVI 3 exposure. But, I figured I'd start a discussion about it.

(Apologies if this thread has already existed. I did not do a search first)

 

[Grayson Payne]

I’d like to know this as well.

 

[Klyde O'Scope]

I leave it up to the lizard. They usually know what they need and/or want.

 

[CasqueAbove]

I leave it up to the lizard. They usually know what they need and/or want.

this is not necessarily true. I have seen cases where Cham’s , and other animals for that mater, have died from not choosing the right needs. Though to be fair, these were terrible setups.
Still , for example, if you have a 6 foot cage with 2 feet just light, 2 feet of basking and 2 feet of UV. He will not go to each part and balance his needs. They will pick a favorite spot or spots which may or may not have enough UV. Where I do believe they can detect UV and will seek it. That is different from knowing what it needs.
If they would seek the proper UV , a dome UV coil would be enough because they would see the needed UV. We know they don’t in those cases.

They simply don’t manage their UV, I wish they would.

So to the main topic, this is something I am very interested in. My setup provides a solid UV coverage, I would say on average they spend 3 to 4 hours a day in UVI 3 to 6. 4 to 5 hours a day in 1+ and the rest 0. I feel like I am right on the edge and don’t want to over due D3, or Vit A , as I use bee Pollen and feed wild food including bees.

I would love to know more.

Can they detect “right amount “ of these in blood tests?

 

[Klyde O'Scope]

this is not necessarily true. I have seen cases where Cham’s , and other animals for that mater, have died from not choosing the right needs. Though to be fair, these were terrible setups.
Still , for example, if you have a 6 foot cage with 2 feet just light, 2 feet of basking and 2 feet of UV. He will not go to each part and balance his needs. They will pick a favorite spot or spots which may or may not have enough UV. Where I do believe they can detect UV and will seek it. That is different from knowing what it needs.

I would say that a setup like that would be more likely to confuse the animal.

For sake of discussion (no condescension intended ), in nature all forms of heat & light are coming from the same source—the sun. As keepers, we try to reproduce nature, which is a challenge to say the least. AFAIK, mercury vapor bulbs come as close to that as reasonably possible, but they're quite expensive, so many/most opt for separate basking & UVB sources, and try to aim them at roughly the same location.

If they would seek the proper UV , a dome UV coil would be enough because they would see the needed UV. We know they don’t in those cases.

They simply don’t manage their UV, I wish they would.

To my knowledge, few—if any—UV sources reproduce the sun exactly, so again, the animals you're speaking of may be confused, and hence unable to balance or manage their lighting needs as they would in nature.

So to the main topic, this is something I am very interested in. My setup provides a solid UV coverage, I would say on average they spend 3 to 4 hours a day in UVI 3 to 6. 4 to 5 hours a day in 1+ and the rest 0. I feel like I am right on the edge and don’t want to over due D3, or Vit A , as I use bee Pollen and feed wild food including bees.

I would love to know more.

Can they detect “right amount “ of these in blood tests?

Are you familiar with the work of Dr. Frances Baines et al?
I would also recommend (if you haven't) searching Google Scholar (not your standard Google )
Here's another resource I found while composing this post (Note the 2nd author is the same Dr. Frances Baines).

There seems (from my cursory glance) to be more written about bearded dragons with regard to UV than chameleons. I don't know if that's due to popularity, number of species (Pogona Vitticeps vs. LOTS) or other reasons.

 

[CasqueAbove]

I would say that a setup like that would be more likely to confuse the animal.

For sake of discussion (no condescension intended ), in nature all forms of heat & light are coming from the same source—the sun. As keepers, we try to reproduce nature, which is a challenge to say the least. AFAIK, mercury vapor bulbs come as close to that as reasonably possible, but they're quite expensive, so many/most opt for separate basking & UVB sources, and try to aim them at roughly the same location.


To my knowledge, few—if any—UV sources reproduce the sun exactly, so again, the animals you're speaking of may be confused, and hence unable to balance or manage their lighting needs as they would in nature.

Yes that was the point. In nature their is balance, we don't have that. That is why they would not have evolved to see UV, but the do seek heat, so when the two are separated they are in fact confused.


I will be checking out these sources. Bearded dragons are not going to have the same UV needs, that is part of the problem. There is more info on Beardies. But we still don't really know the whole UV D3 balance.