MVB & Calcium

[BeardedLion]

So I use a 100w megaray (within 14 inches of the basking spot) as one of my UV sources that runs about 8 hours of the day on the basking spot along with a 75w halogen flood that stays on during all of the day hours. Both are currently above the screen, as I have a vision cage and wouldn't be able to mount them within. I also have a Reptisun 10.0 which is mounted inside, but is without reflector and mounted at about 18 inches up. My beardie can climb his branch if he wants to get near it, which he occasionally does when he doesn't want to be under the Megaray, or when the Megaray has turned off for the evening.

I'm currently using repcal without D3 since I have the mvb, but I'm curious for some input on whether or not the mvb (which is through a screen) is actually allowing my dragon to produce enough D3 to absorb the calcium. D3 has been my #1 foe through beardie ownership, as it has me paranoid constantly (is it too much or is it too little).

 

[BeardedLion]

Decided on feeding rather than enclosures. Could have been either though.

 

[Taterbug]

Have you checked out the uv meter owners group on yahoo? They have a uvb test report for the megaray and you could estimate the uvb levels you are getting, most terrarium screen folters about 35%. As long as you have enough UVB (I shoot for UVI 3-5 at the basking site) the dragon should do the rest and you don't need the d3 in your supplements.

You'll need a yahoo account to view the files
https://groups.yahoo.com/neo/groups/UVB_Meter_Owners/files/LampTestResults/Current-Lamp-Test-Results/

 

[BeardedLion]

Yeah, I've used a UV meter on my megaray and got similar readings (about a third filtered out), but concerning D3, I wasn't sure. There are so many people out there who claim D3 poisoning is easy, and others who say it's hard to achieve. Then there are other that say don't use D3 at all when using an MVB, and some that say use it twice a week (for a juvenile getting dusted 5 times a week with cal).

 

[Taterbug]

Yeah, I've used a UV meter on my megaray and got similar readings (about a third filtered out), but concerning D3, I wasn't sure. There are so many people out there who claim D3 poisoning is easy, and others who say it's hard to achieve. Then there are other that say don't use D3 at all when using an MVB, and some that say use it twice a week (for a juvenile getting dusted 5 times a week with cal).

It depends on how you offer it and all that. Overuse can lead to toxicity in the long term or excessive calcoum uptake possibly, I doubt it would cause acute toxicity. I measured out how much dust would be needed to kill a mouse the size of my dragon and it was a pretty big pile. There really isn't a lot of confirmed information about it (from necropsys or studies) so I prefer to use lights exclusively myself. That way the body is regulating how much d3 it needs as well as how much calcium to absorb from food.

 

[CooperDragon]

This does seem to be a bit of a gray area due to lack of data. I'm in the same camp as Taterbug on this until I have more info. I try to provide a natural-ish level of UV exposure and allow the dragon's body to decide what it needs to do rather than forcing supplementation. Not everyone has the proper lighting to do this or the instruments to measure it out so supplements may be warranted. What readings are you getting under the Megaray at the basking site? As Taterbug mentioned, I try to shoot for 3-5 UVI in the basking site with gradients down to 0 at the sides and in hides. That seems to be a decent average for their natural exposure amounts without having a system that can increase and decrease intensity as the day progresses.

 

[BeardedLion]

What readings are you getting under the Megaray at the basking site?

It's a bit over 3. Without the screen at that distance, it was about mid 4's. But that's at the flat surface of 14 inches. When he gets on his rock, he puts his head up in glory stance, putting him at almost 2 inches above the surface, which is the minimal distance recommended?

I did find an article on UV + d3 supplementation and it's effects on plasma within the UV group on yahoo. I'm not too sure of it's contents at the moment though. Might have to give it a read soon if anyone here doesn't have a summary already, hehe.

 

[Taterbug]

Not sure which article, there are two I know of. One concluded dietary D3 is inadequate and one that found adult females can go something like 80+ days without uvb.

Since you have a meter you can use that to set your distance. I would keep the UVI under 5, 6/7 is the upper "safe" exposure limit wild dragons would use.

 

[BeardedLion]

I borrowed the meter because I can't afford one right now I hope to own one of my own soon though.

 

[Taterbug]

I borrowed the meter because I can't afford one right now I hope to own one of my own soon though.

Ah, well what you have going now sounds to be fine. You could cross reference the isoirradiance chart for the megaray and move a little closer of you want but there isn't really a need too - 3 is fine.

 

[CooperDragon]

I agree, if you were getting a reading of 3, that should be fine. If he sits up then he may pull 3.5-4 at most (you can cross reference the chart for your bulb as Taterbug mentioned) which is still good, especially if he has areas with little to no UVB so he can self regulate.