Are UV bulbs really necessary?

[Arcadiajohn]

Yes of course heat is required and it does add up.

Torts will use tetrachromacy to seek out the heat and emission required at that moment.

I am convinced that keeping most species, not all but most in the uk with no supplementary energy is effectively undersupplying the animal over a period of years. My fear is that this undersupply will build up as Ca is requested back from the bones into the blood and we will see adult MBD type diseases.

This is a theory that is accepted by the Herp vets and certainly makes sense if you stand back and think about it.

Usuable index of say 6-8 for months on end or 3-4 for 2 weeks every year?? I guess something would have to give.

In terms of light selection. We run live tests with Darwin a spur thigh here and he certainly seeks out his boosting zone of UVI5-7 and not heat as they are in differing locations. He does this after thermal regulation. So in my mind and from live tests if the body temp is high enough they will actively seek out UV zones as they require them.

[TillyTortoise]

Originally Posted by Arcadiajohn

Yes of course heat is required and it does add up.

Torts will use tetrachromacy to seek out the heat and emission required at that moment.

I am convinced that keeping most species, not all but most in the uk with no supplementary energy is effectively undersupplying the animal over a period of years. My fear is that this undersupply will build up as Ca is requested back from the bones into the blood and we will see adult MBD type diseases.

This is a theory that is accepted by the Herp vets and certainly makes sense if you stand back and think about it.

Usuable index of say 6-8 for months on end or 3-4 for 2 weeks every year?? I guess something would have to give.

In terms of light selection. We run live tests with Darwin a spur thigh here and he certainly seeks out his boosting zone of UVI5-7 and not heat as they are in differing locations. He does this after thermal regulation. So in my mind and from live tests if the body temp is high enough they will actively seek out UV zones as they require them.

There is a difference between -

How much UVB a tortoise:
1. Needs
2. Has available in the wild

In reality, they probably get a lot less exposure to UVB than you would think. Russian tortoises for example can spend up to 9 months of the year underground, getting absolutely no UVB. Then when a tortoise is 'active' exposed to UVB all day, emerging early in the morning to bask and feed, then spending the majority of the day underground until evening when it has cooled. It's much too hot to be out in the middle of the day in the wild.

Using our HO lights for 12 hours a day, combined with our use supplements we are possibly providing a lot more D3 than is needed.

As a note - It was tipping down today and there was a higher UVB reading outside than my 6 month old UVB lamp was giving off.

[Ozric Jonathan]

I agree that the wild conditions are relevant but I am not attempting to replicate those when my tortoises are 'outside' in the summer. What they are getting is spring-like conditions. I will never be convinced that they would be better off indoors under lamps when they can be outside and active. When the conditions allow.

Because of much lower temperatures, our tortoises spend much longer in the sun than their wild counterparts. This leads to accumulation of uvb exposure. It might not be scientifically proven that this is equivalent to shorter exposure to higher levels but I am not willing to have my pets cooped up all year round when they LOVE the great outdoors.

Mine spend quite long enough indoors getting artificial uvb already John!

[Arcadiajohn]

There is a confusion here, I do not for one second suggest that torts are kept inside.

I truly feel that even though we are now very advanced in terms of UV tech we can never really replicate all the wavelengths of the sun.

I do believe however that the uk exposure isn't enough to energise an animal long term and that they should be supplemented with a lamp. Just the same as they should have access to dietary suppliments.

To rely on the weak output of the uk alone for most species would not be enough I fear. This coupled with the real "Dark art" of synthetic suppliments opens up a whole new world of potetentailly dangerous outcomes.

Wild re-creation is the key. As we become more and more clued up about wild energy had diet our care systems as keepers will continue to improve.

I can't wait for the next 10 years, reptile keeping as a whole will be so different and far more effective and ethical!

John

Originally Posted by Ozric Jonathan

I agree that the wild conditions are relevant but I am not attempting to replicate those when my tortoises are 'outside' in the summer. What they are getting is spring-like conditions. I will never be convinced that they would be better off indoors under lamps when they can be outside and active. When the conditions allow.

Because of much lower temperatures, our tortoises spend much longer in the sun than their wild counterparts. This leads to accumulation of uvb exposure. It might not be scientifically proven that this is equivalent to shorter exposure to higher levels but I am not willing to have my pets cooped up all year round when they LOVE the great outdoors.

Mine spend quite long enough indoors getting artificial uvb already John!

[ClareandCo]

Can we see a picture of Darwin and his set up, please?

Does he also have an outside enclosure?

[Catwoman63]

Judging by my tortoises, the ones kept in a heated shed with a uv tube are more active and go outside, my 2 males that don't have access to a heated shed and only a cold frame in their enclosure are less active and don't eat if its a bit chilly and cloudy and maybe that iwouldnt be good long term especially as we dont have that many sunny days in the uk, if I bring them inside on cloudy and chilly days they are more active and eat, so they do need that extra bit of heat to keep them going and not just uv, so I'm still confused as to whether to provide uv in the sheds during the summer as opinions on here differ, so I think I will continue to provide it as my torts are doing fine, and bring my boys inside when its cloudier and chillier x

[alley cat]

This has become a very interesting thread, thanks to all who have contributed. It occured to me today that I use MVB bulbs so when mine have UVB they also have heat which means that whatever the weather they huddle under the lamps so it is hard to determine if they are under the lamp for heat or UVB. When the lamps are off I do see more natural activity and willingness to go outside to bask (a bit like us and the TV!!) I think tortoises are quite lazy so will go for the easiest option that involves least activity, or maybe I just have couch potato torts!!
I think what I will do is carry on using my 'out of date' bulbs in the greenhouse and carry on with the Nutrobal a couple of times a week

[romski]

Hi guys may I chip in please.

In the first instance The UV levels we get in the UK will be similar to all locations at our latitude. So my Emys turtles originating from Russia and coming from higher latitudes may actually get less UV naturally. (given allowance for pollution and altitude).

There is misconception about how much UV we get here in the UK. I have a great local weather station 2 miles away that measures UV. I have co-related its readings with a Solar meter 6.5 and they are the same near as damn it.
I attach the link
http://www.chilthorneweather.co.uk/a...s_sunshine.php

You will see that the natural UV is really well above anything that a standard lamp can provide (when the sun shines!). The measurement covers both UVa and UVb both of which are important to health.

I keep my torts outside from April to October like OJ. I have a wild pen and a cloche where they can dig in – in the dry. First thing in the morning they sunbathe then when warm they go out foraging. Last thing at night they go back in. They have neither extra heat nor extra UV. This morning at 7.00 one was out foraging in the light rain.

Same applies for my turtles however I am now moving to giving them a green house shelter as well, as I think the principle works well and the provision of the extra warmth is important.

I am of the persuasion that UV light is really important not withstanding that we don’t know how much is needed or utilised.

UVb and UVa light provision to the body is more, much more than just vitamin D3 synthesis and the response to metabolic bone disease. The effects of UV are multifold; the biochemical products effect the reproductive process, the vital organs, the immune system and in addition UV irradiation is anti bacterial/antifungicide which helps deal with skin and shell fungus in turtles.

Tests conducted by Frances Baines and others referenced in her site have showed that the amount of UV passing through the skin depends on the nature of the animal. Shade dwellers seem to have more sensitive skin than high noon baskers and can utilise UVb at lower levels. This variance may apply to tortoise species also – we don’t know.

D3 UV can be compared with vitamins where over a given level additional vitamins cannot be utilised and the body becomes saturated, yet we don’t know what that saturation point may be. Some is absolutely vital masses is not.

Recent work seems to show that temperature is the controlling parameter for basking and that if the animal has reached working temperature in natural sunlight then the UV requirements have been met by default. In my dome where animals have a choice of where to bask then they seem to choose the hot spot as the first option. So in a real sunlight condition once an animal is up to temp, it’s good to go.

In the Mediterranean or North American latitudes the sun strength at sea level and UV available will be the same but considerably weaker than in equatorial conditions say in Africa and Brazil. Yet most of our chelonian friends have the same optimum working temp of about 35 - 40*c. So how is this managed in the different climates.

In the tropics animals seem to get warmed up in the morning and disappear down holes or into shade. In the morning the suns’ heat is less but so is the UV content. Global UV charts tend to show max UV at midday but that’s not when many animals bask. Even in the UK my torts had reached their temp and by midday yesterday they were hiding in the shade. (I actually measure this – I know its sad). I got 40+ on the shell and nearly 5UVI.


As far as costs are concerned I did some light experiment on different set ups which may be of interest.
#1
https://www.youtube.com/watch?v=iVGIBKz_QoE
#2
http://youtu.be/40y3lxbsoxs
#3
https://www.youtube.com/watch?v=M1Ie08bWw80
#4 This is the interesting one.
http://youtu.be/-yH3diMoFXE
#5
https://www.youtube.com/watch?v=M3dy5KhyI70

No tortoises were harmed in the making of this film. It was close; because no sooner than I put on clean paper they decided it was toilet time.

Bottom line is that the halogen Flood lights are very economical at less than a pound a tube. They come in different wattages. The slimline T5 light from Arcadia provides masses of UV for a reasonable cost and at 24watts won’t cost much to run. This set up I only use for animals that never would get natural light that includes UV.
Please remember that normal greenhouse glass blocks UV. It is now possible to get glass made by Pilkington that allows UV to pass through at good levels and I have used this in my dome.

On a last passing note; I have heard so many times that folk have reared and bred reptiles without the benefit of full spectrum (sun)light. Their argument is that if breeding is successful then that is a sign of well being.

I know of a couple that have raised two well balanced children, they have grown and gone to university - all the signs of goodness and rude health. Both parents smoke. If one were to judge purely on the parents’ breeding ability, then they would be judged as healthy. It took masses of science to prove that smoking was bad for health and information continues to build. The argument is perversely true for the health value of full spectrum light that includes UVa and UVb. It will take masses of science to establish the full benefit and simply saying that your animals are healthy without UV, is commenting based on an incomplete data set.
Rom

[kazzabb]

I keep my torts outside from April to October, in each enclosure there is at least one large tort house with ceramic lamps or tubular heaters inside - which are now switched off during the day, as the torts were staying inside all day lolling about. Outside their houses there are 120w basking lamps under a transparent plastic cover. The rest of the enclosure is open to direct sunlight (when it's available). It can be a very warm sunshine day, but he torts still remain under their transparent covers under their basking lamps. I have to switch their lamps off, and physically put them into sunlight, to get them into the sun. Yesterday, when I put the torts into the sunshine to eat, most ate, then took cover under the various grasses which give dappled sunlight, to sleep. As soon as the lamps go back on, they are back under them again. No idea what that's all about, it's got to be hotter under their lamps than in the sun, yet when put under sunlight, they eventually go for dappled shade.
Is ALL uv blocked from greenhouse glass? Those of my torts who don't hibernate, are kept in our large single-pane glass greenhouse (20'x12') from November to April (it has several heaters and loads of basking lamps), but no additional uv lighting. They all get supplements. If NO uv is getting through, then I'll need to reconsider next year's lighting in the greenhouse.
Karen

[romski]

Greenhouse glass does block all UV.

If they are in the greenhouse in the winter there isnt much anyway. I suspect they slow down anyway so growth is slow as well. I suspect its just fine as you have it, if they are outside in the summer. I have also worked your regime and it was fine.

Rom