Small Green Iguana

Vitamins in the diet of reptiles

Captive reptiles should get high-quality food, as varied as possible but providing healthy diet is not as easy as it might seem. Additionally, herbivorous and insectivorous reptiles are exceptionally vulnerable to vitamin deficiencies. This has to do with the foods used in their diet as most vegetables available in stores contain few minerals, vitamins and have an unfavorable calcium/phosphorus ratio, making them a low-value food for herbivores. Insectivores, on the other hand, are problematic due to the limited pool of food insects available in stores. The situation is slightly better for snakes and large monitor lizards, which eat whole vertebrates. Vitamin deficiencies are less common in this group of reptiles. However, this does not change the fact that vitamins in the diet of reptiles should be skillfully supplemented.

Why is Vitamin D3 so important for reptiles?

Vitamin D3 is the most important vitamin in reptile nutrition. Its deficiency inhibits absorption from the gastrointestinal tract into the blood and results in the disruption of the correct calcium-phosphorus ratio. As a consequence, their body seeks to balance this ratio by recovering the calcium stored primarily in the bones. As a result of this phenomenon, a disease called “secondary hyperparathyroidism” develops leading to the development of rickets. Under natural conditions, vitamin D3 is synthesized during exposure to sunlight.

Vitamin D3 facilitates the absorption of calcium from food in the digestive tract. This vitamin is also found in the liver and kidneys of vertebrates. Therefore, animals that eat whole vertebrates (such as snakes, monitor lizards or crocodiles) rarely suffer from deficiencies and rarely need additional supplementation.

Keeping reptiles without access to UVB radiation leads to deficiencies of this vitamin. Learn how and when to supplement vitamin D3.

What is the function of vitamin A in reptiles?

Vitamin A is a group of organic compounds called retinoids, the most important of which is retinol. Retinol is responsible for eyesight. It also affects bone growth and development. In the body, it is responsible for the proper functioning of epithelial tissue of skin, cornea, gastrointestinal tract and respiratory system. It is mainly contained in the liver of vertebrates and fish oil. However, its precursors, or previtamins, are carotenoids derived from plant matter, of which beta-carotene is the most significant. Omnivores and herbivores have the ability to convert carotenoids into retinol. Besides, carotenoids are great antioxidants and they enhance coloration, especially orange and red colors. They are an important element of a balanced diet. It is questionable whether carnivorous reptiles such as snakes and monitor lizards can convert carotenoids into vitamin A and more research is needed to be sure they do have this ability.

What is vitamin K responsible for in reptiles?

Vitamin K plays an important role in bone and blood vessel metabolism, cell growth and apoptosis as well as prevention of vessel and soft tissue calcification. In bone metabolism, it is responsible for capturing calcium from the blood and building it into bone tissue. Vitamin K deficiency is relatively rare and has been observed mainly in crocodiles. Vitamin K is a collective name that includes a group of derivative compounds found in the form of vitamin K1 (phylloquinone), synthesized by plants, and vitamin K2 (menaquinone), synthesized by bacteria. Vitamin K2 is mainly found in animal products and soy fermentation products. The third form is vitamin K3, or menadione, a synthetic analogue of vitamin K that may be a precursor to vitamin K2 in vertebrate organisms. Vitamin K2 is produced by bacteria in the digestive tract. However, long-term administration of antibiotics can significantly reduce the number of probiotic bacteria, causing insufficient production of vitamin K2. Its deficiency is usually manifested by spontaneous hemorrhage, similar to bleeding gums.

Should vitamins be supplemented in reptiles?

Definitely yes, however, it should be done wisely, following the needs of specific animals and using products from trusted manufacturers. They include two supplements by Tropical, which complement each other: Tropical Vigorept Mineral as a source of calcium without vitamins and Tropical Vigorept Multivit as a source of vitamins, including: D3, K, prebiotics, amino acids and carotenoids from algae.

Is it possible to overdose on vitamins in the diet of reptiles?

Sure it is. Therefore, supplement vitamins wisely Keep in mind that vitamin overdoses can be just as dangerous as vitamin deficiencies. To avoid it, you can use Vigorept Multivit. This product includes a teaspoon with instructions for calculating a safe dose. Vigorept Mineral does not contain vitamin D3 so that calcium can be given with each feeding without the risk of overdosing on this vitamin.

Dawid Krótki


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