> My own opinion of UV in dart vivs is that you don't need it
> but it probably won't hurt as long as you are careful. It may
> even have some benefits like enhancement of sexual displays
> that we don't fully appreciate.
>
> (Written by B Brock on Frognet, August 27, 2002)

It's funny how your opinions can change in a year. I've come to think that UV may be more important, at least for pumilio, than I thought when I posted that. My thoughts on UV and pumilio are purely anecdotal. I've had two cases of hypocalcemia in pumilio that were both treated successfully with calcium therapy. I've never seen this in any of my other dart frog species. I know this is too small of a sample to draw broad conclusions but it sets up the suspicion in my mind that pumilio may be more susceptible than some other species. That leads me to wonder why and their use of rather open habitats makes me wonder if they don't take advantage of UV more than some others. Just a guess. I did have one pumilio froglet that lost interest in eating and was clearly going down. I had been feeding a combo of ff and meadow sweeps and it just lost its appetite. I exposed the frog to UVA light and literally within minutes the frog perked up and started eating. That frog is still with me today. Again, only a sample size of one but all this combined has me thinking there are potential benefits from UV light. I now use UVB on all my pumilio and haven't seen any calcium related problems since but, of course, I'm also diligent about supplementation. I guess I've started thinking about UVA/UVB as a safety net where proper nutritional management is sufficient but the UV might provide a bit of buffer against problems. The point about how frog skin handles UV is very interesting to me since I've often wondered if there is a big difference among species. I've heard people talk about seeing pumilio hopping at the edge of the surf along an open beach so I'm pretty sure they can take the UV but what about more strictly forest species?

Brent

~~~~~~~~~~~~~///~~~~~~~~~~~~

But in general UVA does not have an appreciable effect on D3 metabolism adn the peak for UVA is different from UVB. However as many frogs do show the ability to see in the blue end of the light spectrum (Biology of Amphibians) it is possible that UVA enables the frogs to feed more effectively or helps the prey to fit the proper profile to stimulate the feeding respose. Ed
Ed Kowalski
South Jersey


~~~~~~~~~~~~~///~~~~~~~~~~~~

At 20:51 2003-10-06 -0600, Brent L. Brock wrote:

> I exposed the frog to UVA light and literally
>within minutes the frog perked up and started eating.


Right. What does this say, in fact?
If the effect of UV was through vitamin synthesis,
(or calcium metabolism,) would the effect be instantaneous?

There is now doubt that light is important - in many ways. What happens if we just double the number of fluorescent tubes in a viv? How do we experiment in a way that addresses the quality and not the quantity of light?

My vivs sit in a room that has sunlight coming in during winter when the sun is lower in the sky. There is no doubt that it activates the frogs. Again: quality or quantity?

/Lars






~~~~~~~~~~~~~from the notes and contributions of Frognet Patrons~~~~~~~~~~~~~~