UVB not a necessity???

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Millerlite

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I been just letting my tortoises out everyday, Only reason i dont have a uvb light.
 

Gulf Coast

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Waldo gets natural sunshine, his tort table is on a screen porch, so right now I am not worried about a light for him.. But what about winter time? Our winters here are really crazy. lol.. I mean you just never know what you gonna get.. I can't count the days we were running the AC on Christmas Day and wearing shorts... But then have a couple of cold days and its back to sunshine..

God I think this whole debate thread has me more confused than I was before I read it.. lol.. I have never been so SURE and UNSURE at the same time. Who would have THUNK finding that little boy in the back yard would bring on so much damned if you do damned if you don't worries...

I feel like John Travolta in Welcome back Kotter... IM SOOOO CONFUSED!!!!
 

Madkins007

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This is MY OPINION currently, based on a lot of different kinds of input.

UVB is not a biological necessity in the sense that air is, but when you have the right UVB levels for the species and age, with the right bulb type (or sunlight), set up the right way, for the right duration, it seems to be beneficial enough to justify its use.

While many people do not use it (at least in the winter time, etc.), the question is whether their animals would be better off with it? This is an old debate, and one that will not be absolutely solved without controlled, long-term tests.

Even though it is not a necessity, I think it offers several benefits, such as:
- Possibly better skeletal, shell, and organ development
- More natural behaviors (this benefit is well-documented, and is by itself a good argument for some UVA and UVB)
- Mild germ- and mold-fighting characteristics
- Possibly better resistance to respiratory and viral diseases
- Seems helpful (but not necesarily required) for better reproduction

Therefore, to me the 'Best Practice' would be to offer at least some low-level UVB to all ages of all species of tortoises all year as part of an overall proper care program.

But- if you have them outside for part of the year, they have a good diet and cares, and are doing well- I certainly won't knock you for not doing it.
 

terryo

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Even though it is not a necessity, I think it offers several benefits, such as:
- Possibly better skeletal, shell, and organ development
- More natural behaviors (this benefit is well-documented, and is by itself a good argument for some UVA and UVB)
- Mild germ- and mold-fighting characteristics
- Possibly better resistance to respiratory and viral diseases
- Seems helpful (but not necesarily required) for better reproduction


Just out of curiosity, Mark, can you show me what you based your above opinions on?....Care sheets? or something??
 

Redfoot NERD

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Madkins007 said:
This is MY OPINION currently, based on a lot of different kinds of input.

UVB is not a biological necessity in the sense that air is, but when you have the right UVB levels for the species and age, with the right bulb type (or sunlight), set up the right way, for the right duration, it seems to be beneficial enough to justify its use.

While many people do not use it (at least in the winter time, etc.), the question is whether their animals would be better off with it? This is an old debate, and one that will not be absolutely solved without controlled, long-term tests.

Even though it is not a necessity, I think it offers several benefits, such as:
- Possibly better skeletal, shell, and organ development
- More natural behaviors (this benefit is well-documented, and is by itself a good argument for some UVA and UVB)
- Mild germ- and mold-fighting characteristics
- Possibly better resistance to respiratory and viral diseases
- Seems helpful (but not necesarily required) for better reproduction

Therefore, to me the 'Best Practice' would be to offer at least some low-level UVB to all ages of all species of tortoises all year as part of an overall proper care program.

But- if you have them outside for part of the year, they have a good diet and cares, and are doing well- I certainly won't knock you for not doing it.

Mark you don't have the authority [ or personal experience ] to knock anyone.

What good does it do to spend 5X what it costs for a good 'full-spectrum' bulb.. when redfoot tortoises won't make use of them anyway?
Source: Turtletary.. 1998 to present.

Herbivorous tortoises 'need' UVB because they don't get it from their diet.. so they have to bask. So what's the debate all about anyway?

If you or anyone else doesn't give credit where credit is due.. you will be [ questioned ] held accountable.

Terry K
 

-EJ

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Talk to some of those cultures in the norther and extreme southern latitudes. Up until not too long ago in historic terms Rickets was a common problem. This problem was partially resolved through the use of supplements.

What doesn't make sense is how all these reptiles survived long before the UVB lighting. A good number did die but a good number survived.

Also there is no debate whether UVB is beneficial... the debate is whether it is a necessity. As mentioned before... I ran into arguments 10 years ago that the UVB lamps were any good or not. It would surprise you to see the names of some who were dead set against them.


Meg90 said:
So, if I lived without sunlight for 20 years, but still took a multivitamin, I wouldn't have any bad health effects?

That makes no sense.
 

Redfoot NERD

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-EJ said:
Talk to some of those cultures in the norther and extreme southern latitudes. Up until not too long ago in historic terms Rickets was a common problem. This problem was partially resolved through the use of supplements.

What doesn't make sense is how all these reptiles survived long before the UVB lighting. A good number did die but a good number survived.

Also there is no debate whether UVB is beneficial... the debate is whether it is a necessity. As mentioned before... I ran into arguments 10 years ago that the UVB lamps were any good or not. It would surprise you to see the names of some who were dead set against them.


Meg90 said:
So, if I lived without sunlight for 20 years, but still took a multivitamin, I wouldn't have any bad health effects?

That makes no sense.

Bobby Paul.. EJ?
 

Madkins007

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terryo said:
Even though it is not a necessity, I think it offers several benefits, such as:
- Possibly better skeletal, shell, and organ development
- More natural behaviors (this benefit is well-documented, and is by itself a good argument for some UVA and UVB)
- Mild germ- and mold-fighting characteristics
- Possibly better resistance to respiratory and viral diseases
- Seems helpful (but not necesarily required) for better reproduction


Just out of curiosity, Mark, can you show me what you based your above opinions on?....Care sheets? or something??

- Skeletal/organ development- this is what UVB-based D3 does for most vertebrates. (Wikipedia, uvguide.uk.com)
- Natural behaviors- wikipedia, Dr. Mader, and most books on reptile care mention this
- Germ-fighting- a natural effect of UV light (wikipedia)
- Resistance- side effect of germ-fighting, natural behavior, and an article on the effects of UV on immunity
- Reproduction- a benefit noted in many other reptiles- seems to spur mating, egg production, etc. in several species.

Unfortunately, we don't KNOW if UVB does any of this for Red-foots, but since many, possibly even MOST Red-foots live in non-rain forest habitats, it would make sense for them to apply here as well.

Redfoot NERD said:
Mark you don't have the authority [ or personal experience ] to knock anyone.

What good does it do to spend 5X what it costs for a good 'full-spectrum' bulb.. when redfoot tortoises won't make use of them anyway?
Source: Turtletary.. 1998 to present.

Herbivorous tortoises 'need' UVB because they don't get it from their diet.. so they have to bask. So what's the debate all about anyway?

If you or anyone else doesn't give credit where credit is due.. you will be [ questioned ] held accountable.

Terry K

1. Of COURSE I don't have the 'authority' or experience to knock anybody- thats why I don't write answers that say 'if you don't use UVB your tortoise will die' like some people do.

I was only trying to answer Gulf Coast's comment about being confused. I did not realize until you and EJ posted that it was an old post.

2. "What good does it do to spend 5X what it costs for a good 'full-spectrum' bulb.. when redfoot tortoises won't make use of them anyway?
Source: Turtletary.. 1998 to present."

Prove it. You are making an absolute scientific statement here- prove to me that they cannot use the light-based UVB. You challenge me to prove my comments- now it is your turn.

You can show that your indoor animals look good- but that does not prove anything scientifically. Have you had the diet and droppings analyzed to see what the calcium absorption rates are? Have you done side-by-side studies to see the differences with and without?

3. Red-foots bask in their native habitat in Venezuela, Brazil, Panama, some of the islands, Paraguay, and other areas. This has been observed by Moscovitz, Pritchard, Vinke, and others.

4. The debate is whether UVB is a benefit even if not a necessity.

5. What credit is due? I post my sources whenever asked, and you indeed are a source I have used and credited. I obviously did not use you as a source in that opinion statement because you clearly state they don't need UVB... even though your animals are outside in the nice weather.
 

cdmay

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4. The debate is whether UVB is a benefit even if not a necessity.

This above quote by Madkins007 seems to be the center of this very old (and tired) debate.
The fact is, despite some folks denying that redfoots and even yellowfoots bask, these animals do indeed bask both in nature and in captivity. They certainly have in my collection and in all of the keepers care that I know down here in Florida. My big females line up along the western edge of my fence to catch the early morning rays. My hatchlings climb up on top of each other to catch rays. Mind you, this is even during the summer.
In addition I know of many folks who have found both redfoots AND yellowfoots and who have come upon these tortoises while they were basking in exposed patches of sunlight from Colombia to Paraguay. YES, even yellowfoots that according to some avoid sunlight like they were vampires. True, they do prefer more shaded and humid habitats than redfoots but they still expose themselves to sunlight for at least part of the time.
Does this mean that you absolutely must provide some sort of UVA/UVB bulb or direct sunlight for them? I dunno. But if they seek out these things when given the opportunity why not provide it?
Regarding smooth growth without sunlight or UVA/UVB bulbs I would say this: smooth growth on young animals does not in itself mean anything except that their food intake and humidity were well regulated. It does not mean that they will have good internal bone structure or that they will go on to produce large numbers of well calcified and fertile eggs. I would bet that the fertility, egg production and overall health of long term adults is better when they have access to sunlight.
I would also add that the color of their carapace will be more natural as I have seen some captive redfoots (leopard tortoises too) that were raised completely indoors with no natural light that had unusually pale shells. When placed outdoors, the new growth laid down by these tortoises was a healthy black like it is supposed to be.
 

Madkins007

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CD May- thanks for pitching in. The skin color thing makes sense- in most other animals, the melanin (black pigment) in the skin reacts to UV exposure, so why not on tortoises as well.
 

-EJ

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Once again we've kind of burried the point...

UVB is not a necessity for good development. You really can't argue that point.

Artificial UVB produces the same results indoors as not using UVB. It probably is beneficial... but, again, not a necessity.

UVB is NOT sunlight. I think there is no replacement for natural sunlight.

I think that simplifies things.
 

t_mclellan

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cdmay said:
4. The debate is whether UVB is a benefit even if not a necessity.

This above quote by Madkins007 seems to be the center of this very old (and tired) debate.
The fact is, despite some folks denying that redfoots and even yellowfoots bask, these animals do indeed bask both in nature and in captivity. They certainly have in my collection and in all of the keepers care that I know down here in Florida. My big females line up along the western edge of my fence to catch the early morning rays. My hatchlings climb up on top of each other to catch rays. Mind you, this is even during the summer.
In addition I know of many folks who have found both redfoots AND yellowfoots and who have come upon these tortoises while they were basking in exposed patches of sunlight from Colombia to Paraguay. YES, even yellowfoots that according to some avoid sunlight like they were vampires. True, they do prefer more shaded and humid habitats than redfoots but they still expose themselves to sunlight for at least part of the time.
Does this mean that you absolutely must provide some sort of UVA/UVB bulb or direct sunlight for them? I dunno. But if they seek out these things when given the opportunity why not provide it?
Regarding smooth growth without sunlight or UVA/UVB bulbs I would say this: smooth growth on young animals does not in itself mean anything except that their food intake and humidity were well regulated. It does not mean that they will have good internal bone structure or that they will go on to produce large numbers of well calcified and fertile eggs. I would bet that the fertility, egg production and overall health of long term adults is better when they have access to sunlight.
I would also add that the color of their carapace will be more natural as I have seen some captive redfoots (leopard tortoises too) that were raised completely indoors with no natural light that had unusually pale shells. When placed outdoors, the new growth laid down by these tortoises was a healthy black like it is supposed to be.

I have attached photo's of 2 Brazilian CH Rf's taken this morning.
Ages are 2 & 4 They have been outside all but there 1st 6 months of life.
They both show marbling just like I expect in this type of RF.
Mine bask for some portion of the day. Although not extensively.
After about a year the marbling tends to darken considerably.
Whether due to sun light or dirt over time I don't know, But its harder & harder so see the older marbling each year.
Do RF's need UV? Not as much as others I think.
Will I turn off the sun because I think they don't need it? No.
Do I give UV to tortoises when they are inside? Yes.
Do they need it? I duno!
100_1350.JPG
100_1355.JPG
 
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Madkins007

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I found something interesting that I wanted to share, and it has little to do with the 'needed or beneficial' part of the debate.

Dr. Mader's book "Reptile Medicine and Surgery" chapter 84, page 1082, has a section on lighting that I just finally got around to and found something FASCINATING!

A little background. All fluorescent tubes produce SOME UVA and UVB lighting, and different UV meters will measure things a bit differently. Mader offers a chart showing two major meters and what they 'see' in several different fluorescent lamps at 30cm/12" from the center of the bulb.

Now- what is REALLY cool is that they took a glass vial of 'provitamin D3' and exposed it to each tested bulb in a controlled way and measured what percent of it converted to 'previtamin D3'- the stuff the reptiles use- in other words, they simulated what happens in the skin with each bulb. In general, the higher the percent converted, the better the bulb is for doing this.

Here is the chart, as best I can replicate it. I will only show the readings from the Spectronics Corp meter for simplicity, the original graph includes the UVP Inc meter as well. I am also going to rearrange the bulbs from least to most effective, and I added a price comparison:

Bulb - UVA Level - UVB level - % of conversion - price of an 18"/15w bulb on-line
- ZooMed Reptisun 2.0 - 6 - 2 - none detected - $10
- ESU Desert 7% - 30 - 9 - none detected - $20
- Verilux Instant Sun - 4 - 2 - 0.03% - $10
- GE Cool White - 2 - 2 - 0.09% - $6
- ESU Super UV Daylight - 4 - 3 - 0.10% - $13
- ZooMed Reptisun 5.0 - 12 - 13 - 0.13% - $16
- Sylvania 350 Blacklight - 53 - 16 - 0.24% - $8

If I am reading this section of the book correctly (and I am pretty sure I am), plain white fluorescent tubes OUTDID some UVB bulbs in vitamin D3 production, and cost less.

It also suggests a possible answer to the mystery of the 'I never used UV bulbs and got great results' issue in some situations- they may have got enough UVB from the overhead fluorescent bulbs.

What is driving me nuts right now is that there does not seem to be a solid connection between the UV levels and the % of conversion- so there might be something else in play here and I'd love to know what it is!

I've been suggesting a small Reptisun 2.0 or similar as a 'just to be safe' bulb for Red-foots... and maybe I should have been recommending a plain old GE Cool White instead!

A few caveats:
- When talking about the % of converted vitamin D3, I saw no mention as to what was the 'right' percentage. In other words- higher may not automatically be better.
- I saw no mention as to the age of the bulbs. I would assume all were new or had been subjected to the same 'burn in', but it would have been interesting to see the results at the 6 month and 1 and 2 year marks as well. Would the UVB emission of the 'Cool White' hold more steady since it is a lower level and might not burn out the phosphors as quickly? How about the Blacklight since it was MADE to throw off UV for a long time?
 

Madkins007

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Update on the bulb effectiveness. I figured out why some bulbs did better than others with worse specifications. It seems that a very specific wavelength does the optimal D3 change- 295 nanometers, and the bulbs that do best in the percentage column are those that emit the most of that wavelength.

UVB itself is defined as between 280 and 320 nanometers.

Oh, and fluorescent plant lights would emit UVB as well. Isn't that what you use, TurtleTary?
 

-EJ

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One very important bulb has been left out of the study... Active UV Heat/aka Dragon Lamps/aka...

Does Maders new book address the newer lamps. Again... when this who thing started about 30 years ago... there was one lamp... Vitalites... from Europe.

Madkins007 said:
Update on the bulb effectiveness. I figured out why some bulbs did better than others with worse specifications. It seems that a very specific wavelength does the optimal D3 change- 295 nanometers, and the bulbs that do best in the percentage column are those that emit the most of that wavelength.

UVB itself is defined as between 280 and 320 nanometers.

Oh, and fluorescent plant lights would emit UVB as well. Isn't that what you use, TurtleTary?
 

Madkins007

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Actually, EJ, the studies we want seem to have been done by a W. H. Gehrmann. I'm trying to locate some of his articles and papers on the subject. Do you have access to any of the journal sites or anything?

Also- ALL of the bulbs in the study are fluorescent, so the mercury vapors were not included. Maybe in some of Gehrmann's stuff?
 

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As with every vertibrate there are levels. The statement I love to make is that biology is one huge grey area. That is why we have statistics... to provide the numbers to demonstrate we are probably right. There is a black and white in very few cases in every field of biology. That's a very easy statement to make.

Dr. Gehrmanns studies are/were(when I was reading his studies) based on chameleons for the most part. His studies have to be the earliest and most long running. These are/were one of the most delicate reptiles in captivity. They seem to require UVB... why?... can anyone really say... but it is a fact they do. Now... tortoises... the study of UVB on tortoises is in it's infancy. I like to think I had something to do with the movement of the idea. When I expressed how they reacted to UVB I was met with the usual stuff. Notice all I observed is a behaviorial change.

Oh... that was before Calaphratus(sp?)

Again... there is no doubt UVB is benificial to tortoises... it is definately not a necessity.

Madkins007 said:
Actually, EJ, the studies we want seem to have been done by a W. H. Gehrmann. I'm trying to locate some of his articles and papers on the subject. Do you have access to any of the journal sites or anything?

Also- ALL of the bulbs in the study are fluorescent, so the mercury vapors were not included. Maybe in some of Gehrmann's stuff?
 

nearpass

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Madkins007 said:
Actually, EJ, the studies we want seem to have been done by a W. H. Gehrmann. I'm trying to locate some of his articles and papers on the subject. Do you have access to any of the journal sites or anything?

Also- ALL of the bulbs in the study are fluorescent, so the mercury vapors were not included. Maybe in some of Gehrmann's stuff?

There's an article here by W. H. Gehrmann which discusses a few more bulbs, but refers mainly to lizards. Interesting none the less: http://www.naturallighting.com/articles_reptile_lighting_current_perspective.php
 

Madkins007

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Thanks, Nearpass, but that is one of the few I had already found of his stuff, actually on Melissa Kaplan's site.

For both you and EJ- I know a lot of his work deals with lizards, but the mechanics/physics of UV and the bulbs would be species-independent. That is, this bulb will work this way, no matter what is under it- and that is what I was looking for- how the bulbs actually worked.

EJ- I am not jumping on the 'You NEED TO OFFER UVB' bandwagon, but I did think that the study that shows that a lot of the lights used by those ON that bandwagon don' do much was really, really interesting!

By the way, I found a partial PDF from a Gehrmann article (don't ask me how that happened), but it shows the '% of product converted' by natural sunlight in Boston. Obviously, the numbers would be different closer to the equator, and they vary throughout the day and year, but...

At high noon, it is at about 0.2% in January (already more than the Reptisun 5.0 does) to about 1% in March, and almost 7% in July, then to almost 3% in September.

I'm going to try to make a coherent article out of this and post it soon. Rest assured, its focus will be for those that choose to use UV, not saying you MUST use UV.
 
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