Tortoises kept as pets generally require a multivitamin and mineral supplement, especially young, growing tortoises who lay eggs.
Minerals are key chemical regulators and builders of the body. Calcium deficiency is one such example that may lead to serious skeletal issues including deformation of both plastron and carapace bones.
Vitamin D3 is another essential nutrient. This can be obtained either naturally through UV-B light acting upon skin sterols, or it can be taken as a supplement.
Contents
Calcium
Tortoises often need daily vitamin supplements; these usually consist of sugar-based chemicals containing calcium, D3, and betacarotene – although betacarotene may not provide much benefit. Tortoises can get all their required vitamins through diet alone – even iron from eating some raw carrot every day is enough!
Tortoises require plenty of calcium for proper skeletal development and to avoid metabolic bone disease, and for other important functions. It also contributes to their health by supporting cell metabolism and providing essential minerals.
Reptiles need a high quality, natural powder supplement with no additives or phosphorous that contains no heavy metal gypsum such as Plaster of Paris to get their calcium needs met, while others contain vitamin D3 fortification – not recommended as it interferes with their ability to process calcium efficiently and may lead to hypervitaminosis (see the section on Vitamin D3 for more details).
Vitamin D3
Vitamin D (cholecalciferol) is an essential fat-soluble vitamin for calcium metabolism and absorption, and maintaining proper balance between calcium and phosphorous. It’s produced in our skins by UVB light reacting with sterols found in basking temperatures; additionally it can also be found in many calcium/mineral supplements designed for reptile use.
Minerals are chemically active dietary regulators essential for growth and skeletal development; examples include calcium, phosphorous, magnesium, iron and zinc. Cobalt is also crucial as it allows our bodies to absorb and utilise vitamin B12 which is necessary for normal cell function.
Although exact nutritional requirements of vitamins have yet to be established, in natural environments sufficient quantities should be available from tortoises selecting their own diets. Although it has been speculated that tortoises fed high protein diets may suffer anatomical shell and skeletal deformities from feeding high protein diets, however this has never been established from published research studies.
Vitamin A
Fat-soluble vitamin A is essential to immune function, vision (it gives eyes their red hue), normal cell growth and communication between cells; in reptiles it is an integral part of their protein which allows them to absorb calcium more readily.
Vitamin A can be easily obtained through green vegetables and most specialist reptile supplements, though it’s essential that any multivitamin contain true vitamin A in the form of retinol acetate or palmitate and not simply beta-carotene as this could lead to deficiencies for some reptiles.
Provide tortoises with daily doses of multivitamins containing adequate calcium as part of their care routine is an integral element. Hatchlings, juveniles and active egg laying females should receive multivitamins with a high calcium:phosphorous ratio (Ca:P) and vitamin D3, such as Nutrobal, ProRep Calci Dust or Ace High products on most days.
Vitamin C
Water-soluble vitamin that can easily be absorbed. As an antioxidant, it protects against damage caused by free radicals produced during oxidative stress, while being essential to producing collagen for bones, cartilage, and connective tissues. Furthermore, it serves as an precursor for riboflavin that assists the body to utilise iron more efficiently.
Tortoises in the wild obtain ample vitamin C by eating ripe fruits and fungus and browsing rotting vegetation, but in captivity this can be more challenging as their nutritional requirements must be fulfilled through providing fresh fruits and vegetables.
Many tortoise keepers prefer using multivitamin supplements like Nutrobal which contains calcium, D3 and other vital vitamins for daily care of their tortoises. Experienced keepers also often rely on Rep-cal as an alternative source of high calcium/low phosphorous products when feeding Nutrobal is unavailable.
