My Reptile Diet

By John F Taylor

Introduction

Green Iguana Iguana iguana is a popular lizard and they can make for an excellent captive reptile pet given they are provided for properly, unfortunately many new Green Iguana I. iguana owners fail to do so. To this day Green Iguanas I. iguana are one of, if not the most abandoned pet reptile. For those not dropped off at the nearest park or animal shelter there is a laundry list of ailments and afflictions which many new owners encounter. This can almost all be attributed to lack of knowledge regarding two major aspects of reptile husbandry or herpetoculture as it is sometimes known. These aspects are nutrition and lighting.

We’re going to cover lighting first as this aspect alone seems to be an issue that is rarely addressed in the realm of herpetoculture. When lighting for diurnal lizards whether they are herbivores (I. iguana, Uromastyx, etc.) or omnivores such as bearded dragons Pogona vitticeps you should, no should is a misnomer you must provide not only proper vitamin supplementation but also what is known as UVB or ultraviolet light in the B spectrum. UVB is provided either via florescent bulbs or also by what are known as mercury vapor bulbs. For more on the types of bulbs and which are best we recommend the UV Guide http://www.uvguide.co.uk/.

UV lighting in a basic understanding causes a chemical reaction within the bloodstream that allows diurnal lizards to process calcium and withdraw from it the chemical vitamin D3. Without proper lighting diurnal lizards are incapable of properly processing calcium which can then cause such maladies as MBD or metabolic bone disease and many other diseases such as renal complications.  As long as you understand that UVB and Vitamin D3 are inseparable then you are well on your way.

UV lighting must be replaced every 6 months as the ultraviolet aspect of the bulb wears out over time. One more thing before leaving the subject of lighting. Please stop using colored lights on your reptiles for viewing them at night. This doesn’t do them any good, leaving the light on at night to see them actually disturbs their circadian rhythm as I have shown in my piece Colored Lights and Reptiles.

Feeding the Green Iguana

Before the advent of ‘complete’ diets such as the dried pellets now offered for sale herpetoculturists would feed their Green Iguana I. iguana and other herbivorous lizards a mix of dark green leafy vegetables and some fruits. As the complete diets become more prevalent I’m confident that more reptile owners will begin to use them. I do not subscribe to any one particular brand of complete diet as they are all relatively similar in their nutritional values and all are acceptable forms that can be used by Green Iguana I. iguana owners.

For those that want to provide a more or less natural diet for their Green Iguana I. iguana there is a lot of information available on which diet is best coming from various ‘experts’. Now then, before going further I would encourage you to read my piece on ‘experts’ and why you should never listen to just one person’s opinion. Too many people claim this or that vegetable is a calcium blocker and while it is true for some vegetables it is not as extreme as it is made out to be in most literature. This will come as a shock to many reptile keepers and I will clarify below.

If you feed a diet consisting only of say Kale or Spinach which contain Oxalates then calcium blockage may be an issue. I have yet to actually read a veterinary study that states a reptile fed a regular diet which included Kale or Spinach developed calcium absorption issues. Now with that said I do believe that if the reptile was fed only Kale and Spinach then it is theoretically possible that calcium would be blocked from being absorbed into the blood.

Personally, for my herbivorous lizards to which I feed a diet of greens I buy a grocery store bag of mixed spring greens which I would mix with romaine that had been washed and chopped into bite size pieces. Along with that a variety of seasonal melons and fruits are added to the mix as well. I avoid citrus as this may cause stomach irritation. To this mix of greens and fruits I add a calcium powder supplement. Calcium supplements have some controversy about them as there is really as of yet no one who is able to actually say without a doubt how much calcium a reptile needs and therefore no real measurement to tell us if we are giving enough, except when an issue develops. So what is the best practice? Personally, I dust with enough calcium and vitamin powder to coat the vegetables but not so much that I cannot see the green through the powder. I know this is still somewhat vague and believe me we are still searching for the answers regarding this. So for now, your best bet if you’re not comfortable with the semi-natural diet is to purchase a complete diet that has been tested and proven time and again to provide the nutritional values that your particular species requires.