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Discussion starter · #21 ·
I cant afford a solarmeter at this time. Are there any approximate guidelines for which strength bulbs and distances to use, with a glass cover,? I am aware that glass does block UV, interestingly, I haven't actually found any studies of any kind that this is the case, merely hearsay and experience of others.
Evaluation of UVB reduction by materials commonly used in reptile husbandry - Michael Burger - 2007 - Zoo Biology - Wiley Online Library

http://www.guardian.com/stellentdev/groups/climaguard/documents/native/gi_004941.pdf

Those were two of the studies that I found within a page or two of google scholar.
Ed
 
Thanks. I will need to expand my vocabulary when using scholar. I didn't use any variation of "transmitting" or "transparency". Dumb. Lesson learned.

Evaluation of UVB reduction by materials commonly used in reptile husbandry - Michael Burger - 2007 - Zoo Biology - Wiley Online Library requires a fee... I cant afford it. Bugger. The joys of college.

Now I feel stupid and poor :D

Added it to the list of articles to read when I can...

And... I don't feel quite as stupid. There are many articles dealing with additives to glass that absorb/block UV, or UV blocking plastics, but very few that actually refer to or measure UV transparency, and those only mention it in passing. Looks like most researchers are interested in blocking UV. Not much interest in allowing it through, apart from flora/fauna related interests.
Interestingly, http://www.guardian.com/stellentdev/groups/climaguard/documents/native/gi_004941.pdf only provided manufacturers specs. Lots of information on glass, but no independent studies. Looks like "Evaluation of UVB reduction..." moves to the top of the reading list.
 
Did you check for this through your university library system? They may already be paying for access to it - as a result you could access. I know that our university (a rather small one) provides access. You could also request an interlibrary loan for this article (probably free maybe 3 bucks for the copy).

Go to your library page search for the Wiley Library database then find the Zoo Biology journal.

Burger, M.R., Gehrmann, W.H., Ferguson, G.W. (2007). Evlauation of UVB reduction by materials commonly used in reptile husbandry. Zoo Biology, 26(5), 418-423. (volume 26 issue 5).

If that proves unsuccessful pm me.

- ryan
 
Did you check for this through your university library system? They may already be paying for access to it - as a result you could access. I know that our university (a rather small one) provides access. You could also request an interlibrary loan for this article (probably free maybe 3 bucks for the copy).

Go to your library page search for the Wiley Library database then find the Zoo Biology journal.

Burger, M.R., Gehrmann, W.H., Ferguson, G.W. (2007). Evlauation of UVB reduction by materials commonly used in reptile husbandry. Zoo Biology, 26(5), 418-423. (volume 26 issue 5).

If that proves unsuccessful pm me.

- ryan
I will definitely try that. Now that I think about it, I have barely touched the school's library system. They definitely have intersystem loans. I'm going to see what they have. Thanks for suggesting that. Its strange, I guess mostly because of the convenience of google, I don't think of using the library. I am going to change that now!
 
I will definitely try that. Now that I think about it, I have barely touched the school's library system. They definitely have intersystem loans. I'm going to see what they have. Thanks for suggesting that. Its strange, I guess mostly because of the convenience of google, I don't think of using the library. I am going to change that now!
Good answer! :)

Keep in mind, your student fees pay for things like access to the journal in question and many many others. Our uni provides access to all sorts of things that many people don't know about but pay through the nose for (e.g., access to tons of high end software through remote desktop services).

- ryan
 
i am gonna start experimenting with this in some of my frogs, can you guys recomend a good fixture and bulb?
This is what I use......... not sure if IKEA is in the US.....................

As most of you know I put real importance on providing UVb for all my frogs. I made up a lamp a few years ago that did the job but was a bit of a pain to use - bring a chair to rest it on to light some of the viv.

So I decided that this week while it was half term that I would 'build' something more practical. We had been over to Ikea and Global light (ÂŁ14) caught my eye as being perfect for adaption. It bends and twists in all directions and fastens to any shelf and all of my vivs are on some sort of shelf I thought I'd give it a go.

Here's the lamp before I 'adapted it.
Image


Then using the Arcadia parts I already had

Lampholder
Image


Reflector
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and bulb D3+ 10%UVb
Image


Then it was just a matter of removing the lamp fitting and rewiring in the Arcadia lampholder which fits really neatly on the swivel head that the Ikea lamp comes with.

Here's a close up of how the original wiring that is internal to the lamp fits the Arcadia lamp
Image


and finaly a couple of shots of the new UVb set up in action - I am really pleased with it and it will make UVb day (once a week each viv gets one hour of UVB lighting) so much easier.

here it is on the Retic viv
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and on the White Foot viv
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It was just so easy to convert and looks like it has been manafactured by Arcadia - I should patent the idea!

Regards
Graham
 
Discussion starter · #32 ·
I have noticed that the frogs seem to have an awareness of UVb strength as they 'bathe' about 3 inches farther back than when the doors are closed and the UVb is going through the Optiwhite glass I use on all my viv doors.
Not singling you out, just using this to illustrate some information that is circulating round the hobby..

Using O. pumilio as a model there isn't any indication that the frogs can actually see UVB (or UVA) light see http://core.ecu.edu/biol/summersk/s...ebpage/articles/Summers2003_Variation in spectral reflectance in D. pumilio.pdf as they lack the structures in thier eyes to see into that frequency (specifically see
There is little or no evidence that D. pumilio does have UV sensitive cones (E. Loew, pers comm.) which would allow these frogs to percieve reflectance in that region of the electromagnetic spectrum. Morever our measurements suggest that all the different morphs of D. pumilio have very little reflectance in the UV, implying that UV colours may not be important for social interactions in this species
We also know that the frogs avoid excess exposure to UVB see http://people.oregonstate.edu/~blaustea/pdfs/HanBiotropica2007.pdf .. which indicates that the frogs can detect UV exposure, but we aren't sure of the exact method but it is probable that it may at least depend on the circulating levels of vitamin D3...

Some further comments,

Ed
 
Quick question. So do frogs require special lighting like reptiles(have I missed this in my reading)? Or is it an only occasional special lighting. Or do the powder supplements/dustings cover the need for it?
 
In short (someone correct me if i'm wrong):

Frogs (and many other species) use UVB to ultimately increase the amount of circulating D3 in their system. They also self regulate exposure to UVB depending on level of D3. In other words - if they have an optimum level of D3 already in their system then adding UVB is not likely going to do any good and will likely cause the frog to avoid the source (i.e., hide). If you are providing D3 from another source you shouldn't need the UVB.

To make things more difficult - most aquariums we use have glass that filters UVB. There are some types of glass that allow UVB through but it is very expensive and not likely to be found in a typical tank.

Do you need UVB - not really. But the frog does need D3 to be healthy. You choose how the frog gets it.

- Ryan
 
Discussion starter · #35 ·
If you are providing D3 from another source you shouldn't need the UVB.

Sort of... The data that is coming out is that if the frogs (and other taxa) have access to UVB, then they modify thier behavior to reach a higher level of circulating D3 than can be attained through D3 supplied only through the diet. (See for example http://www.academicjournals.org/JPAP/PDF/pdf2011/July/Verschooren et al.pdf). What we are seeing in the broadest terms is that the frogs get by with the D3 supplied through supplementations but if they have the option they increase the D3 in thier bodies. People often forget that D3 is important for many other functions in the body outside of the use of calcium in the bones...

Your frogs can do fine without any exposure to D3 (and this is documented in many literary sources and by anecdotal practices) but cutting edge is indicating that it benefits them to have some access...


Ed
 
Maybe I missed it by accident, but does anyone know where to find research on the commonly used UV-bulbs and their longevity? I've heard that many of them stop emitting UVB after only a couple of months, which would make it a very expensive practice.

Anyway, I have started an experiment with my E. tricolor 'Echeandia' of which I was told should become alot more yellow when using UVB. They are subadults right now, but I'm wondering what will happen. I also plan to try UVB on young A. silverstonei when they start breeding again. I've seen them being very much attracted to any sunlight that fell through the window into their tanks. This, and the problematic rearing of offspring, made me decide I should definitaly try it.
 
If they can reach higher levels of d3 from uvb exposure, how come they can overdose on oral d3 but don't overdose on uvb producing d3?

Sort of... The data that is coming out is that if the frogs (and other taxa) have access to UVB, then they modify thier behavior to reach a higher level of circulating D3 than can be attained through D3 supplied only through the diet. (See for example http://www.academicjournals.org/JPAP/PDF/pdf2011/July/Verschooren et al.pdf). What we are seeing in the broadest terms is that the frogs get by with the D3 supplied through supplementations but if they have the option they increase the D3 in thier bodies. People often forget that D3 is important for many other functions in the body outside of the use of calcium in the bones...

Your frogs can do fine without any exposure to D3 (and this is documented in many literary sources and by anecdotal practices) but cutting edge is indicating that it benefits them to have some access...


Ed
 
Discussion starter · #39 ·
If they can reach higher levels of d3 from uvb exposure, how come they can overdose on oral d3 but don't overdose on uvb producing d3?
Through

1) Feedback inhibition of vitamin D-25 hydroxylase which prevents the conversion of previtamin D3 to D3 in the liver
2) feed back inhibition of the transport of the converted provitamin D3 to the circulation system which results in it converting to supersterols in the skin via continued exposure...,
3) behavioral modification to prevent excess isomerization of provitamin D3 to previtamin D3....

Oral ingestion of D3 avoids all of the protection provided by the feedback mechanisms and if excess is ingested resulting in toxicity... which is one of the reasons it was/is used as a rat poison..

Ed
 
Discussion starter · #40 ·
Maybe I missed it by accident, but does anyone know where to find research on the commonly used UV-bulbs and their longevity? I've heard that many of them stop emitting UVB after only a couple of months, which would make it a very expensive practice.

Anyway, I have started an experiment with my E. tricolor 'Echeandia' of which I was told should become alot more yellow when using UVB. They are subadults right now, but I'm wondering what will happen. I also plan to try UVB on young A. silverstonei when they start breeding again. I've seen them being very much attracted to any sunlight that fell through the window into their tanks. This, and the problematic rearing of offspring, made me decide I should definitaly try it.
Typically you won't see a change in yellow pigments using UVB as those are either genetically controlled (pterins) or are taken up from the diet (carotenoids). Typically the carotenoids provided to the frogs consist primarily of beta carotene with lesser amounts of other yellows depending if they are provided in a supplement (very few supply a range of carotenoids) or in some cases potentially through "gut loading" the invertebrates. It is good to keep in mind that carotenoids require a source of lipids in the diet to uptake and absorb carotenoids, and that there is interference between some carotenoids for uptake. This means that if you are using a supplement high in beta carotene it may not matter what carotenoids are in the diet of the invertebrates as the beta carotene ,may prevent the uptake to any significant degree.

It should be noted that melanin is typically the pigment produced to ward off increased levels of exposure to UVB if required...

I would suggest trying a variety of carotenoids in the diet of the frogs and the tadpoles as that is more likely to increase pigmentation.

Ed
 
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