I agree with Cheri on this (well actually on most things).
Here is why:
There is a lot of evidence that dietary D3 is not absorbed well through the intestines in reptiles and much of it never gets into the blood stream. But there is also a risk of overdose if too much is given. The question is not whether a dragon can be maintained on dietary D3 supplements, but whether an average hobbyist can consistantly achieve the EXACT balance (not to mention the novice first time owner).
Hypervitaminosis D is just as dangerous as hypo. In fact the effects can occur much more quickly and be even harder to reverse then MBD. To much D3 can (just a slight oversupplementation over a period of time) cause various health problems. Dietary D3 is very hard on the kidneys. Over time it can cause mineralization of the internal organs and blood vessels. It WILL draw calcium out of the bones to keep the blood calcium level correct if to much is given. These are all facts, no speculation, no having to experiment on generations of dragons. A good understanding of biology is all it takes.
http://www.chameleonjournals.com/vet/index.php?show=6.Vitamin.D3.and.Calcium.html
http://www.icomm.ca/dragon/kidney.htm
Improper supplementation is also a leading cause of excessive phos. levels in bearded dragons. For proper bone health your animals should be getting a 1:1 or 2:1 Ca
ratio. Overuse of D3 is a leading cause of unbalanced Ca levels.
Check out the Calcium Phosphorus ration Section of this page:
http://www.icomm.ca/dragon/calciumdeficiency.htm
A disturbing quote from the FDA website on pet supplements:
Briefly, it said that FDA could not call a substance a "drug" or "food additive" if it met the definition for a dietary supplement and was not already regulated as a drug or food additive. Thus, it shifted the burden of the manufacturer having to prove a product was safe before it went on the market to the FDA having to prove it was unsafe before it could be removed. This prompted a sizable increase in the number and range of dietary supplements available on the market today.
And:
U.S. consumers spend more than $11 billion a year on cat and dog food, according to the Pet Food Institute. And pet food manufacturers compete for these dollars by trying to make their products stand out among the many types of dry, moist, and semi-moist foods available. Pet food packaging carries such descriptive words as "senior," "premium," "super-premium," "gourmet," and "natural." These terms, however, have no standard definition or regulatory meaning.
More scary pet product websites:
http://www.state.ia.us/government/ag/latest_news/releases/mar_2003/Pet_Medicine.html
http://siriusdog.com/articles/dog-food-industry-labs-cruelty-rendering.htm
http://www.pcoc.net/dog-food.htm#FOOD NOT FIT FOR A PET
If you clicked on those links above you now know a lot more about the pet industry then you want to. The pet industry has GREAT lobbyists that have allowed it to stay fully self-regulated and held only to voluntary guidelines. These products are NOT produced in controlled and quality checked conditions. You have no idea what is in the supplement you are giving to your animals. Even when the companies have good intentions they DO MAKE MISTAKES, OFTEN, and they do not have extensive quality checks to catch them. How can you trust your pets health to something made by an unregulated corporation with $$ being the bottom line? Lets say that Joe, the guy that oversees the Calcium/D3 production process has a bad day. Say he messes up the D3 content one day. You buy that bottle of calcium and how long does it last you? At least 4 months for just one animal….what happens to that animal getting either too much or too little D3 for 4 months?
You think you know the pet food industry. Click on those articles and see how vets are speaking out about the “rendering” of companion animals for petfood. Pets are being fed back to themselves. Its happening. When you put Fluffy down and leave him at the vet to “dispose of” there is a service that buys them from your vet by the pound. Through the internet vets are able to get that info out: http://www.pcoc.net/dog-food.htm#FOOD NOT FIT FOR A PET
This is the industry that you buy supplements from. (disclaimer, there are good intentioned companies out there. I believe RepCal is a good intentioned company, but they DO make mistakes. Their process is not perfect and does not compare to the standards and testing that human products undergo. For example, a few months back they were off on the dye content of the pellets. These mistakes happen all the time and do not always present themselves in the form of very colorful feces. Whether its dye content or D3 content these mistakes go straight to the store shelves)
Lets try this example. Say I am feeding my dog a certain food for its whole life. My dog is going to do ok with this food because nothing in it is outright deadly. But, the food uses a small amount of Vit C as a preservative. Over my dogs life this is going to slowly destroy his kidneys. Looking at my dog is not going to show any problems without blood panels. My do will be mostly healthy for his whole life. But my dog will die several years earlier then he might with good kidneys. You can’t base claims of a product being healthy on the limited observations of one animal.
Its ridiculous to claim that MVB does not work because you didn’t see any difference over a very short period of time. That shows a complete lack of understanding about the entire nature of the argument. This is not an overnight thing. D3 is not something that you can adjust the levels of visually. You don’t know if you are supplementing correctly unless you have blood regularly drawn and tested. How can you trust a NEW reptile owner to find the golden balance of Calcium, D3, and Phosphorus?
Without doing daily blood panels you can not tell what the levels of calcium and D3 are in your dragon. When you give D3 it is like you are giving a medication. It gets into the blood stream whether they need it or not. When a dragon makes its own D3, its body regulates the amount. When you feed it YOU decide the levels, and you do it blindly. Being even slightly off over the years will cause major problems.
http://home.att.net/~chameleons/zoomeduvb.html
http://www.exoticpetvet.net/dvms/mbd.html
http://www.mapleveterinaryclinic.com/reptiles.htm
http://www.exoticpet.com/newpage17.htm
Someone asked about studies. Unfortunatly most research costs money to do and therefore is not freely distributed. Unless you put money and effort into it you are not going to find real research on dietary D3. You need to look at scientific studies and not hobbyists on forums. This means going to Veterinary Universities, they have research libraries that have many studies and articles. This is a pretty common research project and there are many dissertations on the subject that are available in the libraries. These are Copywritted material though, so they won’t be posted online. I also suggest buying and reading: Reptile Medicine and Surgery by Douglas Madar
Health and Welfare of Captive Reptiles
by Cliffor Warwick, Fredric L. Frye, James B. Murphy
Vitamin D: Physiology, Molecular Biology, and Clinical Applications
by M. F. Holick
Common Reptile Diseases and Treatment
by Shawn P. Messonnier
Husbandry, Medicine and Surgery in Captive Reptiles
by Fredric L. Frye
This is where you go to find studies and scientific information, and not speculation.
Here are some more sources if you go to a veterinary library.
Alberts, Allison. 1994. Ultraviolet light and lizards: more than meets the eye. The Vivarium 5(4):24.
Ball, James C. Vitamin D3 synthesis: A comparison of the UV B output of commercial lights and sunlight. Northern Nevada Herpetological Society, V(3):7.
Barten, Stephen L., DVM. The medical care of iguanas and other common pet lizards. Exotic Pet Medicine I 23(6):1213-1249
Bernard, JS, OT Oftendal, PS Barboza, ME Allen, SB Citino, DE Ullry, and RJ Montali. 1991. The response of vitamin D deficient green iguanas (Iguana iguana) to artificial ultraviolet light. Proc Am Vet 1991:147-150.
Gehrmann, William H. No UV from tungsten filament incandescent light. ARAV 2(2):5. 1992.
Goldstein, Robert. 1990. Spectrum lighting. Reptile & Amphibian Magazine, Mar/Apr 1990.
Richards, Ann. 1994. Understanding your reptile's lighting needs will help you keep it healthy. Reptiles 1(1):24.
Use of full spectrum lighting at the Arizona Sonora Desert Museum. Iguana Times 3(1):11. March 1994.
No, I didn’t just type this. I just went back to a bunch of things I have written before and copied and pasted. So if you recognize parts you have probably seen them…
I tend to argue the extreme of what I am talking about because it makes the statments clearer, but I do believe that there are experianced keepers that are qualified and able to maintain bearded dragons on dietary D3 supplements. I would NEVER however recommend that a novice try to mess with the delicate balance and risk hypovitaminosis. I am not saying individuals should not decide on their own to do it. But people who are qualified to do this do not need a forum to tell them it can be done. They are experts on the species. Supplements are NOT the best method of delivering D3. They can be dangerous and even deadly. That is why UVB is recomended.
Kakadu Dragons
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then don't like the answers they get and complain about those nice enough to share their knowledge and experience. this i will never understand and i see alot of this on this forum.
*pat on back*