Chameleons regulate UV exposure in response to dietary vitamin D3

[drewtt]

Hey all,

I just came across this very recent article (in press 2009, Physiol Biochem Zool), in which the authors are able to show significant changes in basking behaviours in response to dietary vitamin D3. Specifically, panther chameleons maintained on a diet with "low" D3 had an intrinsic response to seek out basking spots with higher levels of UVB, and subsequently produce more D3. On the other hand, panthers kept on "high" D3 diets preferrably basked in spots on the lower end of typical UVB exposure. It has previously been demonstrated that panthers can "self-regulate" D3 levels; although, the dietary D3 notion is a novel concept, or at least is novel to published literature (2003, Physiol Biochem Zool).

Maybe this seems intuitive to some, but it was a nice read, and does provide sufficient evidence to suggest that panthers not only bask for thermoregulatory purposes, but also bask in specific areas for more controlled D3 regulation, depending on already-present endogenous levels.

I guess this might help explain why one of my male panthers started hanging out on the bottom of his enclosure when I accidentally left a 10.0 bulb over him, instead of his usual 5.0 (appetite & D3 staying the same).

Anyway, just thought some members might like to read it, if they already haven't come across it. The pdf (and even a converted txt file) is just over the limits for uploading, so I'll just provide the pubmed link: http://www.ncbi.nlm.nih.gov/pubmed/12695986?ordinalpos=1&itool=EntrezSystem2.PEntrez. Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.P ubmed_Discovery_RA&linkpos=1&log$=relatedarticles& logdbfrom=pubmed

Enjoy,

Drew

 

[Chameleons Canada]

Hi Drew,

Great article, thanks!

 

[luckykarma]

Yes, thanks!

 

[Docility]

im glad they are continuing to do research on D3 levels in Chameleons. though not a new concept to the reptile world, but one that need to continue in the right direction. Chameleons will photo regulate, and have been monitored doing this in the wild. the 2008 exoterra expedition video is worth a good watch, and it is very informative

 

[Brad Ramsey]

This is why I believe that basking spots and UVB lights should be located in separate areas.
The animal should have the opportunity to warm up without having to be exposed to UVB radiation and vice versa.

-Brad

 

[yoza717]

This is why I believe that basking spots and UVB lights should be located in separate areas.
The animal should have the opportunity to warm up without having to be exposed to UVB radiation and vice versa.

-Brad

Interesting thought.....someone needs to add this to the study also, to see if chameleons can distinguish the difference between a heat source light and a UVB source light.
I would be interesting to see if the D3 supplimented chameleons would just use the basking light, if the lights were separated.

 

[sandrachameleon]

Interesting -thanks drewtt!

I keep the heat bulb at the back of the cage in the middle. The UVB tube is along one side, front to back. The chameleon thus can choose UVB only (by being near the front of the cage), UVB and Heat (by being towards the back between the UVB tube and heat bulb) or heat only (by being towards the back on the opposite top side of cage from the UVB tube.

 

[Docility]

Interesting thought.....someone needs to add this to the study also, to see if chameleons can distinguish the difference between a heat source light and a UVB source light.
I would be interesting to see if the D3 supplimented chameleons would just use the basking light, if the lights were separated.

i supplement with D3, they still bask under the UVB tube. The cage is set up fron to back 5.0, and the middle right side is a 125W blue UVA day bulb (i dont know why, but this thing does not put off enough heat to burn tested by holding my hand against the screen for 5 mins and nothing just really warm lol) and in the back a 2.0 uvb (mainly for light) , but the weird thing is they would rather bask under the 2.0's instead of the 5.0's. the 2.0 puts off a very strong white light, and the 5.0 puts off a blue tint light, and the UVA puts off just clear looking light no tint. so maybe they like the 2.0 light spectrum better?

 

[drewtt]

Interesting -thanks drewtt!

I keep the heat bulb at the back of the cage in the middle. The UVB tube is along one side, front to back. The chameleon thus can choose UVB only (by being near the front of the cage), UVB and Heat (by being towards the back between the UVB tube and heat bulb) or heat only (by being towards the back on the opposite top side of cage from the UVB tube.

I do, and always have used this arrangement as well, Sandra -- no complaints thus far!

i supplement with D3, they still bask under the UVB tube. The cage is set up fron to back 5.0, and the middle right side is a 125W blue UVA day bulb (i dont know why, but this thing does not put off enough heat to burn tested by holding my hand against the screen for 5 mins and nothing just really warm lol) and in the back a 2.0 uvb (mainly for light) , but the weird thing is they would rather bask under the 2.0's instead of the 5.0's. the 2.0 puts off a very strong white light, and the 5.0 puts off a blue tint light, and the UVA puts off just clear looking light no tint. so maybe they like the 2.0 light spectrum better?

Docility, it also makes somewhat of a difference as to how far away from the bulb they are basking. Being right under the 2.0 might be the equivalent of being quite a ways away from your 5.0 for them. Maybe your guy gets enough dietary D3, so being under more intense UVB would augment too much D3 production? I guess the take-home message might be that, provided that you are supplying sufficient D3, proper heat gradients, proper UV lighting, the chams find the right basking spot(s) and kind of take care of the rest of it themselves Smart little critters, aren't they?

Drew

 

[jojackson]

This is why I believe that basking spots and UVB lights should be located in separate areas.
The animal should have the opportunity to warm up without having to be exposed to UVB radiation and vice versa.

-Brad

But Where does that happen in the wild Brad? Nature knows best, so does your cham/s!

That said, most of us use tubes atleast as long/wide as the cage so that generally is provided
despite ambient air at the top being warmer. Do you have UV at the cool end (Bottom)?