UVB?

[ehopkins12]

I've been following this care sheet http://www.turtletary.com/redfootcare.htm
It's been recommended tome by a few people and seems to make sense, The only thing I really don't understand is why a redfoot doesn't require UVB. I've even heard people say that it's bad for them. I'm not saying I don't buy it, I just would like to have it explained to me so i can understand. My redfoot is about 12 weeks old (I believe) and I've read that babies that young especially don't require it. Is this true? or should my redfoot be getting UVB?

 

[Candy]

The thing about baby Redfoots is they live in the rain forest and hide (from predators) most of the time so they don't get much light. I take my Cherryheads out and let them get natural sunlight and I also have a UVB bulb on them, but I only put it on one side of the enclosure. Lets see what others opinions are.

 

[ehopkins12]

yea I've got a 15w full spectrum zoo med daylight bulb on the cool side that he doesn't go to very often. I'm pretty sure that puts out some uvb...but not totally sure. ill probably just let him outside and he can get sunlight that way. but if I do that how long should he be out? can he get too much sun?

 

[Yvonne G]

The benefit to having a UVB bulb on a tortoise is that the tortoise's body makes Vitamin d3 from the UVB. And Vit.d3 is required in order for the calcium they ingest to work. However, Redfoots eat a bit of carion or animal protein, and they get their vit.d3 from the animal protein, so its not as important to provide a UVB bulb for a turtle/tortoise that can get the vitd3 from other sources.

Also, the light you refer to doesn't provide UVB.

 

[Tom]

Terry K. is the expert on this one and the writer of that care sheet. No one will give you a better explanation and answer your questions better than he. You could always PM him. He has had tremendous success with his redfoots using the techniques on that care sheet. I've read his care sheet, talked with him about it and I couldn't agree with him more. His info is current and cutting edge. All of the 10-20 year old care sheets will contradict some of what he says. Terry knows better now. His tortoises taught him the right way to do it.

 

[ehopkins12]

Terry K. is the expert on this one and the writer of that care sheet.

whats his username?

 

[Broda805]

bringing an old thread back for a question, so they get their d3 from animal protein and such but your not suppose to suppliment that till they are over 6 months if i read correctly. so does this mean for 6mo> babys they are fine without a uvb artificial source but require some daily natural sunlight? would it be bad if they didnt get to go out everyday or every other day?

 

[Tom]

Terry K. is the expert on this one and the writer of that care sheet.

whats his username?

Sorry. I missed this. Redfoot NERD is Terry's user name.

 

[terryo]

I've been following Terry's care sheets now for over two years. There are other breeders who disagree with him on the UVB. Each one is adamant with their care sheets. On the side with the long tube light, I use a 5.0 UVB instead of just a tube light. My Cherry Head only goes out in the summer, and I feel it's not going to hurt. With everything else I usually follow Terry's care sheet.

 

[Madkins007]

I've been following this care sheet http://www.turtletary.com/redfootcare.htm
It's been recommended tome by a few people and seems to make sense, The only thing I really don't understand is why a redfoot doesn't require UVB. I've even heard people say that it's bad for them. I'm not saying I don't buy it, I just would like to have it explained to me so i can understand. My redfoot is about 12 weeks old (I believe) and I've read that babies that young especially don't require it. Is this true? or should my redfoot be getting UVB?

This is not as clean-cut of an issue as you might like it to be.

The idea that too much UVB can be bad is true. The actual vitamin, vitamin D, can build up in tissues and be a health issue. This is not a problem from UVB from sunlight since the body has a failsafe process. It CAN rarely be an issue with dietary vitamin D, and there is some thought that it can be an issue with UVB lighting. While they need vitamin D, they really don't need a lot.

Not all UVB is created equal. The very best UVB are those rays closest to UVC, while the rays in most UVB bulbs are mostly those near the UVA range. These rays can cause eye damage, sunburns, cancer, etc. if they are overdone- too bright, too powerful, too long of a day.

Interestingly, all fluorescent tubes emit at least some UVA and UVB. More interestingly, 'cool white' bulbs can actually offer more of the best kinds of UVB than some 'low level' specialty UVB bulbs.

Now, lets look at baby Red-foots.

First- contrary to some popular beliefs, Red-foots are not primarily a rain forest species. Certainly some are found in the deep forest, but most Red-foots are found in savannahs and scrub forests. In fact, all 'southern' Red-foots are found outside of the rain forest. Thus- MOST baby Red-foots get good sun exposure sometimes. (Also- even deep forest gets decent UVB according to actual readings taken.)

Babies do hide most of the day, and actually get a big chunk of their energy from the yolk sack for many months. It is certainly possible that they get all the vitamin D they need from there as well, at least for several months.

Bottom line: Terry's method works for him and a lot of other people- and methods used by other keepers that incorporate reasonable levels of UVB work for them. Without an in-depth research project we may never know which one is the 'right' way to go. After all, Terry does suggest using plant/aquarium bulbs so they may be getting UVB almost by accident.

My opinion is that using reasonable lighting, including UVB, has several benefits (vitamin D, germ-killing aspects, better skin colors, etc.) and no real downsides other than the price of the bulbs. It seems like a reasonable insurance policy.

 

[Bryan]

I've been following this care sheet http://www.turtletary.com/redfootcare.htm
It's been recommended tome by a few people and seems to make sense, The only thing I really don't understand is why a redfoot doesn't require UVB. I've even heard people say that it's bad for them. I'm not saying I don't buy it, I just would like to have it explained to me so i can understand. My redfoot is about 12 weeks old (I believe) and I've read that babies that young especially don't require it. Is this true? or should my redfoot be getting UVB?

This is not as clean-cut of an issue as you might like it to be.

The idea that too much UVB can be bad is true. The actual vitamin, vitamin D, can build up in tissues and be a health issue. This is not a problem from UVB from sunlight since the body has a failsafe process. It CAN rarely be an issue with dietary vitamin D, and there is some thought that it can be an issue with UVB lighting. While they need vitamin D, they really don't need a lot.

Not all UVB is created equal. The very best UVB are those rays closest to UVC, while the rays in most UVB bulbs are mostly those near the UVA range. These rays can cause eye damage, sunburns, cancer, etc. if they are overdone- too bright, too powerful, too long of a day.

Interestingly, all fluorescent tubes emit at least some UVA and UVB. More interestingly, 'cool white' bulbs can actually offer more of the best kinds of UVB than some 'low level' specialty UVB bulbs.

Now, lets look at baby Red-foots.

First- contrary to some popular beliefs, Red-foots are not primarily a rain forest species. Certainly some are found in the deep forest, but most Red-foots are found in savannahs and scrub forests. In fact, all 'southern' Red-foots are found outside of the rain forest. Thus- MOST baby Red-foots get good sun exposure sometimes. (Also- even deep forest gets decent UVB according to actual readings taken.)

Babies do hide most of the day, and actually get a big chunk of their energy from the yolk sack for many months. It is certainly possible that they get all the vitamin D they need from there as well, at least for several months.

Bottom line: Terry's method works for him and a lot of other people- and methods used by other keepers that incorporate reasonable levels of UVB work for them. Without an in-depth research project we may never know which one is the 'right' way to go. After all, Terry does suggest using plant/aquarium bulbs so they may be getting UVB almost by accident.

My opinion is that using reasonable lighting, including UVB, has several benefits (vitamin D, germ-killing aspects, better skin colors, etc.) and no real downsides other than the price of the bulbs. It seems like a reasonable insurance policy.

That's the first that I've ever heard of that. Great info!

 

[Madkins007]

Interestingly, all fluorescent tubes emit at least some UVA and UVB. More interestingly, 'cool white' bulbs can actually offer more of the best kinds of UVB than some 'low level' specialty UVB bulbs.

That's the first that I've ever heard of that. Great info!
[/quote]

I first ran into this in Mader's book "Reptile Medicine and Surgery", and have found other references on-line. Google "Gehrmann UVB" to find some articles on this. Interesting stuff!

 

[Redfoot NERD]

You can provide them with UVB bulbs or tube lights or natural sunlight.. I've tried them all!

Bottom line - they don't really like that much 'light'. So when you take them outside as hatchlings, etc. they will seek 'shelter' [ out of the direct sunshine ]. If they are running around more active it's because they're seeking shelter.. not because the UVB is activating them.

I've raised redfoots from hatchlings to become breeders using the caresheet prescribed..... which can be duplicated ANYWHERE in the world! [ I have them in all corners of the U.S. now ] Others have and are reporting the same results. It doesn't take 8 million specimens and 27 years to prove otherwise. This is NOT a science.. although some think it should be.

The main reason I prescribe "wait until they are 6 months or 3" SCL" is because it's too easy to O.D. these little guys as hatchlings. The "if 1 is good.. 2 must be better" mentality is 'killing' [ figuratively ] our hatchlings! And keep in mind that they live for a long time.. [ 80+ years ] so in this case "less is best"!

As far as others not agreeing.. let's see pics of their results of raising hatchlings using UVB bulbs, etc. right out of the egg. All I hear is verbage(sp.?) - where's the evidence?

Do what you will.. it's your $$$

NERD

---

yea I've got a 15w full spectrum zoo med daylight bulb on the cool side that he doesn't go to very often. I'm pretty sure that puts out some uvb...but not totally sure. ill probably just let him outside and he can get sunlight that way. but if I do that how long should he be out? can he get too much sun?

A redfoot enclosure should have low to mid 80's F throughout their enclosure.. NO "basking-hotspot" or cool side.. same temps all over. He doesn't like all of the light or cool temps is probly why he doesn't go there!

NERD

 

[terryo]

I have to agree with you Terry K. Until I read your care sheets, I had a cool side and a hot side. Pio never went on the cool side. It was a waste of space. When he was about three months, I made the whole enclosure 85 degrees and it's been that way for two and a half years now. Humidity is always in the 80's range. Low light, warm high humidity...you simplified it for me. Now that he's older and outside a lot, I do see him sitting in the sun for a while, but mostly he will sit under a plant.

 

[chadk]

Here is some more info on the topic of UVB:


http://redfoottortoise.com/Redfoots_in_the_shade.htm

Redfoot tortoises in the shade, do they need UVB?
A common question from new Redfoot tortoises is "Why do I need a UVB light. Don't Redfoot tortoises live in the shade?"

Aside from the fact that they aren't strict deep forest dwellers, the following shows that they do get UVB even in deep shade. Here in South Carolina I have confirmed this using a Solarmeter 6.2 UVB radiometer.

Excerpts from:
DIFFUSE COMPONENT OF THE SOLAR ULTRAVIOLET RADIATION IN TREE SHADE A.V. Parisi, M.G. Kimlin, J.C.F. Wong, M. Wilson Centre for Astronomy and Atmospheric Research, University of Southern Queensland, Toowoomba, 4350, Australia.

J Photochem Photobiol B. 2000 Feb;54(2-3):116-20.

Comments added by me are in red italics.

INTRODUCTION
•UV exposure is due to sunlight received as both direct and diffuse radiation.

•This diffuse radiation may constitute a significant component to the UV exposure received by eyes and skin as it is incident from all directions and difficult to minimize with the usage of hats, tree shade and shade structures as it can reach surfaces shaded from the direct sun light.

•Others have measured the spectral global and diffuse solar ultraviolet radiation. The diffuse UV increases with decreasing wavelength (UVB wavelengths are shorter than UVA so UVB penetrates deeper into the shade) due to the stronger scattering at the shorter wavelengths.

•In tree shade, a larger proportion of the UV exists compared to that in full sun may be as a result of the diffuse component (... adding to the total UV amount from direct sunlight areas). However, no previous research has considered the diffuse UV irradiances in tree shade.

•This paper presents: the results of quantitative measurements of the diffuse erythemal* and diffuse UVA (320 to 400 nm) at ground level on a horizontal plane at a Southern Hemisphere sub-tropical forest floor. This paper has provided the first set of quantitative data of diffuse erythemal UVB and UVA in tree shade at a sub-tropical Southern Hemisphere latitude.
CONCLUSIONS
•Over the summer, approximately 60% of the erythemal UV*(UVB) radiation in the tree shade is due to the diffuse component. Similarly, approximately 56% of the UVA radiation in the tree shade is due to the diffuse component.

•In the tree shade these diffuse UV percentages are relatively constant from the morning to noon to afternoon periods. In comparison, in full sun, there is a decrease in the percentage diffuse UV from morning to noon to afternoon.

•The exposures to diffuse UV on a horizontal plane were measured in the tree shade.

•The high diffuse UV component in the shade may result in high UV exposures to not only parts of the body on a horizontal plane that are not protected, but also, equally high UV irradiances to parts of the body, including the eyes and face, that are not UV protected.
*UV Erythemal action spectrum for humans has been employed widely for assessing the UV effect on human skin. The value of the sensitivity is normalized to unity at 298 nm (the UVB wavelength also most efficient for Vitamin D3 synthesis).

The whole paper can be viewed here

But there is more !!

Photochemistry and Photobiology 78(2):180-183. 2003
doi: 10.1562/0031-8655(2003)078<0180:SUBPSS>2.0.CO;2

Scattered UV Beneath Public Shade Structures During Winter¶
D. J. Turnbull*, A. V. Parisi, J. Sabburg
Centre for Astronomy, Solar Radiation and Climate, University of Southern Queensland, Toowoomba, QLD, Australia


102*To whom correspondence should be addressed at: Centre for Astronomy, Solar Radiation and Climate, University of Southern Queensland, Toowoomba 4350, QLD, Australia. Fax: +61-7-46311530; [email protected]

Abstract
Broadband field measurements were conducted beneath three different-sized public shade structures, small, medium and large, during winter in the Southern Hemisphere. These measurements were compared with the diffuse UV to quantify the relationship of the UV under and around the shade structures to the diffuse UV. For the shade structures, a relationship between the diffuse UV and the UV in the shade has been provided for clear skies and solar zenith angles (SZA) of 49–76°. This allows the prediction of the UV in the shade of these structures if the diffuse UV is known. The ultraviolet protection factors for the three shade structures ranged from 1.5 to 5.4 for decreasing SZA. For the greater SZA of 70–76°, the erythemal UV in the shade was 65%, 59% and 51% of that in full sun for the small, medium and large structures, respectively. For the smaller SZA of 50–53° the erythemal UV in the shade was 35%, 41% and 18% for the small, medium and large shade structures, respectively. From this research it can be concluded that the UV radiation levels in the shade in winter could cause erythema and other sun-related disorders.

 

[terryo]

I just want to add one more thing. I always kept a low wt. 5.0 long tube UVB on one side of his enclosure since I have him. I figured it couldn't hurt.