The Vitamin A Mystery in Chameleons Unleashed

08/12/2024

Vitamin A

Vitamin A is a vital fat-soluble nutrient essential for the overall health and well-being of chameleons. It exists in two primary forms: 

  1. preformed vitamin A (retinol) found in animal products, unfortunalety, insects contain very minute to no retinol and 

  2. provitamin A (carotenoids) found in plant sources, particularly colorful fruits and vegetables such as carrots and leafy greens.

For chameleons, one of the most crucial roles of vitamin A is its contribution to vision. It is essential for the production of rhodopsin, a protein in the retina that helps these reptiles adjust to varying light conditions, enhancing their ability to hunt and navigate their environment.

Vitamin A also plays a significant role in supporting the immune system, promoting healthy skin, and maintaining the integrity of mucous membranes, which are vital for respiratory and digestive health. Additionally, this vitamin is important for cellular communication and proper growth, especially in juvenile chameleons.

While a deficiency in vitamin A can lead to various health issues, including vision problems, skin problems including wrong shedding, and a weakened immune response, excessive intake can also be harmful it leads to destructive changes in liver. Chameleons can obtain sufficient vitamin A through a balanced diet comprised of insects and plant matter such as pollen and gutload, ensuring their nutritional needs are met for optimal health and vitality.


Chameleons can not synthetise retinol from provitamins A

Chameleons, like many reptiles, have limited ability to convert carotenoids from their diet into vitamin A (retinol). Therefore, they rely on obtaining vitamin A from their food sources directly. In the wild, chameleons acquire vitamin A through the following means:

  1. Insects: Chameleons primarily eat insects, which can be a source of preformed vitamin A. Some insects may have a higher content of vitamin A due to their own diets, particularly if they consume plant materials rich in carotenoids.

  2. Small Vertebrates: Depending on the species, chameleons may also consume small vertebrates, such as small birds, small mammals like rodents and their babies or other reptiles. These animals possess preformed vitamin A in their tissues.

  3. Plant Matter: While chameleons are known primarily as insectivores, they may occasionally ingest plant matter like leaves and especially bright colored flowers (full of pollen) and fruits (rarely). However, since they cannot efficiently convert carotenoids into vitamin A, they typically obtain limited to no vitamin A from plants. Even bee pollen does not contain it.

The mysterious source of A

So, the crucial question arises: where do chameleons obtain vitamin A naturally, especially considering their size limits their ability to feed on snails or smaller vertebrates? This detective story is quite intriguing, and the answer is encoded within a simple yet fundamental question:

If vitamin A is so vital for their survival and sources are seemingly scarce, what behavior must have evolved to facilitate its acquisition?

The logical answer is a strong preference—akin to a frenzy—when encountering sources rich in vitamin A. This leads us to explore what food items chameleons might preferentially eat above all others. Based on numerous observations in captivity and my 40 years of field studies, I can assert that there are specific items chameleons significantly prefer, often eating them even in the presence of humans, which can bias natural behaviors. In such cases, chameleons may abandon their usual caution, driven by their desire for these food items.

The answer lies in three types of insects:

  1.  praying mantises, 

  2. wasps, and 

  3. flies. 

Now, what connects these insects to the availability of vitamin A? 

While they are indeed typical insects, the answer is more complex. These insects have dietary habits that allow them to ingest small vertebrates, leading to potential vitamin A in their digestive systems. 

  1. Some species of praying mantis can capture small geckos or lizards }even chameleons). 

  2. Wasps often scavenge on the remains of dead animals, ingesting pieces of liver or meat. 

  3. Similarly, flies are attracted to decomposing carcasses, particularly from larger mammals.

Hence, I believe this is the key to understanding why chameleons vigorously pursue praying mantises, wasps, and flies over other insects. It is the evolutionary advantage of consuming these insects, which offers a higher likelihood of obtaining the vital and inevitable and rare vitamin A compared to other available food sources.

It has been demonstrated through practice in captivity that the administration of vitamin A can be somewhat tricky for chameleons. When given on a regular basis, excessive vitamin A can lead to a range of non-specific health issues, which often mirror problems associated with vitamin C deficiency. These issues can include gular edema, eye problems like proptosis or inflammation, and skin issues including shedding difficulties.

However, if vitamin A is provided intermittently and not continuously—as occurs naturally in the wild—these problems typically resolve themselves. This reflects the fact that chameleons in their natural habitats do not consistently consume high doses of vitamin A; instead, they obtain it sporadically and irregularly through their diet.

Captive implications 

As such, mimicking the natural feeding habits of chameleons in captivity is essential for their health and well-being.

So in captivity, t is however inevitable to supplement chameleons with processed vitamin A in either of the following forms:

  • multivitamin supplement mixtures (out if the available ones, only Arcadia Earth Pro A is evidently containing it, others declare but lack it),

  • small vertebrates such as pinky mice, geckos, anoles (once per 5-8 weeks),

  • small snails,

  • liver, eventually meat (administered as an occassional but regular - e.g. biweekly - gutload of feeders).


Author: Petr Nečas
My projects:   ARCHAIUS   │   CHAMELEONS.INFO