Reptile & Amphibian Forums

I found this abstract on the net. Pretty interesting.

Husbandry
J Herpe Med Surg 13[2]:14-17 Summer'03 Nutrition Notes 10 Refs

* Brian M. Aucone, BS, William H. Gehrmann, PhD, Gary W. Ferguson, PhD, Tai C. Chen, PhD, Michael F. Holick, PhD, MD
* Oklahoma City Zoo, Department of Herpetology 2101 NE 50th Street Oklahoma City, OK 73111, USA
Two studies were conducted to determine the suitability of the Westron Corp. self-ballasted mercury vapor lamps in the captive maintenance of the chuckwalla lizard, Sauromalus obesus. Initially, preference for basking under either a Westron lamp or an incandescent flood lamp was measured in a separate enclosure involving five individuals selected from a group of eight juveniles. Following this, the eight chuckwallas were divided into two groups and maintained for fifteen months in indoor enclosures illuminated with either an incandescent flood lamp and fluorescent Sylvania 350 BL combination or a single Westron self-ballasted mercury vapor lamp. Snout-to-vent length (SVL), body mass, and cloacal body temperatures were measured every two weeks. After nine months, the lizards were radiographed to assess bone density and blood was collected for assay of 25-hydroxyvitamin D. No significant differences in SVL and body mass growth rates, cloacal body temperatures or bone densities were observed between the two groups. The serum 25-hydroxyvitamin D concentrations for lizards exposed to the incandescent lamp/Sylvania 350BL combination were significantly less than those measured in lizards exposed to the Westron lamp and wild-caught lizards. Furthermore, the Westron lamp maintained 25-hydroxyvitamin D at levels comparable to those observed from a wild-caught sample. Observations support a preference for basking under a Westron lamp. These data suggest that the Westron lamp is at least as effective as an incandescent/blacklight combination in maintaining desert dwelling chuckwallas and that either setup may result in adequate vitamin D production sufficient to sustain healthy bone density. [Abstract]

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I knew those lamps were a waste of money LOL. I guess if you insist on having higher serum levels, then those are the lights for you. I personall would rather pay under $5.00 for a bulb...

John

Actually had some time to browse the forums for the first time in months. Just have to throw my paltry 2-cents in.

In my opinion, MVBs are NOT a waste of money. While the limited studies on mercury-vapor bulbs are not conclusive, my personal experiences with them are not(to me at least). I can say without a doubt that diurnal lizards do MUCH better under MVBs than regular incandescents and/or UVB fuorescents.

Why exactly this is so is the perplexing question for me. Whether it's from increased D3 sythesis or exposure to more-natural visible wavelengths(psychological benefits at least), i have no idea. What i do know is that each species of lizard that I have properly exposed to MVBs on a consistent basis have invariably become more active, healthy, vibrant, productive(eggs) and content(when compared to other types of lighting). The only lighting better(IMO) is natural, unfiltered sunshine.

Having said that, i also strongly believe that MVBs are not necessary to raise and maintain a healthy diurnal lizard. But, they are very beneficial. The most important things for bulbs (for diurnal lizards at least) is the actual heat and luminens (brightness) they produce. An everyday household bulb(provided the watts and luminens are adequately high) and a healthy diet/clean enclosure are the keys to healthy lizards.

I like to use MVBs to acclimate WC lizards that i occasionally get in late fall. MVBs are great for cycling or gravid females. MVBs are great for depressed, sick lizards. MVBs are great for lizards that are normally housed outdoors(chucks, uros, DIs, HLs etc, etc).

My biggest complaint about MVBs and the only valid reason i know of to not get some is that they are expensive and they burn-out really easily. I've tried 5 different brands over the last 4 years and almost all of them have burned-out in under 6 months.

It's nice to see the regulars are still around this forum.
cheers everyone

loren
Sundial Reptile

Enjoyed your input. But I had to ask EXACTLY what you meant when you stated, "An everyday household bulb(provided the watts and luminens are adequately high) and a healthy diet/clean enclosure are the keys to healthy lizards." Are you saying that in the lighting department, a high-wattage regular incandescent bulb is all that's needed for successfully keeping diurnal basking lizards, as opposed to a heat bulb AND some sort of good UVB or mercury vapor bulb? A 150 watt bulb or two, good food, and a clean cage will do the trick? I'm about to send off my Xmas list to my kids, and the list is always composed of basking bulbs, 5.0 Reptisun bulbs, and whatever other herp supplies I need at the time. Do I ask for the UVB bulbs this year, or can I vastly lower my wants and needs to several packages of 150 watt Walmart incandescents?!?

In MY experience, iguanas, chucks, and uros all end up with tremors and anorexia without annually-replaced UVB bulbs shining on them every day, given that my creatures unfortunately get almost no natural sunlight.

I had a T-Rex Active UV Heat bulb shining on my big egyptian uro. He LOVED it and stayed out of his cave and under the light all day long. The bulb lasted about 6 months, which wasn't great considering the price. I wish I could provide each of my lizards one of these bulbs, but they are too expensive for 6 months of shine, and now I THINK I'm hearing that this bulb isn't even essential for good lizard health. It's very confusing to go through everyone's comments in this forum and come away with such hugely conflicting impressions.

Anyway, did I read you correctly that herpers can get away without UVB bulbs as long as they use really hot incandescents?

I tried to be as clear as possible, but this can be a sticky issue with some people.

NO, I'm not recommending that people forgo UVB bulbs. I'm simply stating that the relative impact that UVB has on a lizard should not be over-stated. As long as one supplements properly and provides an adequately hot and bright bulb, UVB emmission is not COMPLETELY necessary. Still, your lizard will be happier and healthier(perhaps less delicate)if you provide them with a mercury-vapor bulb(MVB).

Make no mistake, UVB is good for a lizard. All diurnal lizards benefit greatly from exposure to UVB. But other things are more important than UVB when it comes to maintinaing the health of a lizard. Things like adequate heat, a proper diet, proper feeding frequency, bright light& high UVA emission; A clean enclosure, proper supplementation and a relatively stress-free environment; etc, etc, etc.
How do you think people kept diurnal reptiles alive before all the UVB bulbs came out?

I would, however, highly recommend getting a MVB instead of the fluorescent UVB bulbs. The fluorescents cost almost as much, emit a fraction of the UVB and should technically be replaced every 6 months. MVBs last longer, penetrate further and emit at least 5-10x the UVB. If your MVB burnt-out in 6 months, most companies have a warranty and will at least pro-rate you for the cost of a replacement(eg.; a 1 yr warranty gets you 50% off your replacement bulb if your bulb burnt out after 6 months).

The bottom-line is this: Any lizard can be healthy for months without UVB as long as they are cared-for and supplemented properly. Don't break your bank account just because your UVB bulbs burnt-out. At the same time, make sure to pick some up when you do get extra money. It's as simple as that. No stress as long as you are satisfying every other element of your lizards requirements.

As I stated in the last post, there are certain species that benefit more from MVB bulbs. These are the herbivorous and desert dwelling lizards (like chucks, DIs, HLs, Uros, iguanas,etc etc.) I give all of these species real sunshine for 5-7 months/year. This allows me to go longer without UVB bulbs for many of these species. If your lizards do not get high levels of UVB sometime in the year, then many of the species i previously mentioned will become more delicate and potentially problematic if proper conditions are not provided.

YES, a 150-watt Walmart bulb would be just fine for your lizards as long as you supplement properly and as long as your lizard does not have some ongoing deficiency. If you are getting a bulb just to provide heat, luminens and UVA, then there is no reason to spend more than the cost of a Walmart bulb. If your diurnal lizards DO NOT get real sunshine, you should EVENTUALLY get a MVB if you really care about their long-term physiological and psychological well-being.

Hope this clarified my position on this

loren
Sundial Reptile

Thanks so much for posting the article. I wrote off to Westron asking where a person in my area can obtain those bulbs. And then I started wondering ... we're always cautioned to go easy on the reptile vitamin/mineral supplements. I was THINKING that was because too much D3 was dangerous. If both groups of lizards did well clinically in the Westron study but the Westron group showed higher blood D3 levels, how do we know they weren't approaching the toxic level as opposed to a safer level found within the incandescent/BL lizards? Presumably, a lizard isn't likely to overproduce the vitamin endogenously, and the Westron level is probably still way lower than what natural sunlight would provoke. Just a fun thought ... Anyhow, if I can obtain those bulbs and they aren't way out of my price range, it's a done deal that I'm switching. Neat study, neat article, awesome lizards.

more. I'm not sure what to conclude from that abstract relative to lizard husbandry needs. Clearly the merc-vapor bulb resulted in D levels closer to natural light but I find myself asking:
1-Since bone density and growth was similar, are there any health disadvantages to the lower blood levels? If so, what are they?
2 - I assume there were no dietary differences for the two groups. Could D3 supplement in the food for the group with the cheaper lighting have yielded the higher D measurements. and if so, the real question is how much is enough but not too much.
Any comments?

I will see what it says. I am not sure if anyone knows how much is too much. I think they can only be compared to animals in the field to see how they compare. I imagine they can od on D3. I know they can on calcium causing kidney stones and calcium plugs in the oviducts. It would only make sense that they would not supplement when doing an experiment such as measuring calcium blood levels as a result of light quality.