As far as possible, tortoises should be allowed to graze on wild foods, as opposed to supermarket greens and pelleted tortoise food. A well-balanced, varied, natural graze will provide a diet which not only is high in fibre, but will contain some of the essential minerals and trace elements necessary for the optimum health and slow growth of your tortoise.
A question that often follows a discussion about diet is:
The answer is fairly complex as a lot depends on the type of diet fed to the tortoise in captivity, the types of plants it grazes on, and the composition of the soil in which the plants have been grown. In essence, yes, tortoises in captivity, from that very first mouthful, do require supplements to be added to their daily diet. However, the type and amount of supplement required will vary, depending on how the tortoise is kept, the food it is exposed to and, in some cases, the species of tortoise.
Natural unfiltered sunlight plays a significant part in the production of vitamin D3, which plays a major role in forming bony tissue in chelonians. The levels of UVB present in countries like the UK often fall far below that required of individual species and therefore artificial UVB lights and normally a vitamin D3 supplement may be required, depending on where you live and what species you keep.
In captivity a keeper has full responsibility to ensure that the diet provided equates to that found naturally in the wild.
Below you will find a list of some of the various supplements currently available over the counter for tortoises, together with a brief and simple explanation of their use. They contain various essential minerals, vitamins and trace elements which might be found in the tortoise's natural habitat in the wild, but which might be missing in the captive environment.
Arkvits: a blend of Nutrobal and Ace-High (2:1). It provides a Calcium:Phosphorus ratio (Ca:P) of 30:1 and contains vitamins A, C and E, making it suitable for the maintenance of adult reptiles.
Ace High: contains high levels of vitamin A, C and E. These higher levels of vitamins are beneficial during periods of stress and disease. Vitamin A and E are both involved in helping the body resist infection. Vitamin A is essential for healthy mucous membranes such as mouth, lungs and gut. Vitamin E has been shown to boost the immune system. Vitamin C is rapidly utilised by the body when a tortoise is under stress.
N.B. It is advised that Ace High vitamin supplement is only used under the advice of a veterinarian because of the risk of overdosing the tortoise with vitamins.
Calci Dust: like Nutrobal provides a good range of vitamins and minerals, but it doesn’t include Vitamin D3. It is designed for use on the days that Nutrobal isn’t used. Perhaps one to choose in climates where there are high levels of UVB from natural sunlight or when using good quality UVB lighting where there is no need to provide vitamin D3 every day.
Calcium Carbonate: is by far the purest form of calcium (40% calcium) available for chelonians (containing NO phosphorous).
Cuttlefish is commonly given to caged birds, cuttlefish bone can be purchased from most pet stores and should be left around in tortoise enclosures for the tortoises to freely nibble on. It is a relatively good source of calcium and helps the tortoise to keep its beak from becoming overgrown.
Often tortoises will only eat cuttlefish when it has been left out in the enclosure through all weathers. It may be particularly attractive to female tortoises when they are gravid, and to juveniles going through ‘growth spurts’. Leaving a piece of cuttlefish bone in the tortoise enclosure allows the tortoise to self-regulate its intake of calcium.
Limestone flour is another good form of calcium (38% calcium) which can be purchased from agricultural farm food stores cheaply and used daily. It can be offered sprinkled over food, left in mounds for the tortoise to eat at will or even applied to the weed bed to enrich the growing plants.
Nutrobal is a high calcium balancer, vitamin and mineral supplement which includes Vitamin D3. Nutrobal offers a high Ca:P of 46:1 but it doesn’t have a wide range of trace elements.
N.B. Nutrobal containers purchased from different suppliers may come in different coloured packaging.
Rep-Cal + D3:
Rep-cal is a 100% oyster-shell calcium supplement with added vitamin D3 but it is phosphorous-free; so a good choice for tortoises of all ages.
Reptavite is a reptile supplement with only a low Ca:P of 2:1 but it does have an extensive range of vitamins and trace minerals. Many experienced keepers will offer this one day a week, leaving out other minerals and vitamin supplements on this day.
Reptivite: Calcium levels inadequate for growing tortoises and not recommended by experienced tortoise keepers.
Standard Bone Meal: Although standard bone meal offers a good volume of calcium (approximately 30%), it contains a high level of phosphorous (approximately 15%). It has also been known to contain contaminants such as aluminium, arsenic, mercury, and cadmium and is therefore best avoided.
Vionate:Vionate is a vitamin and mineral supplement. It has a good range of trace elements but a poor Ca:P of only 1.4:1. It is useful for giving to juveniles once a week and to breeding females.
Ingredients: Limestone. Protein 0.32%, Ash (mineral) 100%, Fibre 1.4%, Oil 0.8%
Ingredients per gram: 200 mg calcium & 150 IU vitamin D3, plus vitamins A C E K B1 B2 B6 B12 folic, nicotinic & pantothenic acids; biotin choline niacin and minerals P Na Fe Co I Mn Zn Se Cu.
Ingredients: Vitamins/Minerals (1Kg)
K 86.00 mg
B1 42.00 mg
B2 82.00 mg
B6 13.00 mg
B12 0.16 mg
C 4000.00 mg
Biotin 0.60 mg
Iron 598.00 mg
Cobalt 5.80 mg
Iodine 31.00 mg
A 34000.00 iu
D3 34000.00 iu
E 216.00 iu
Copper 54.00 mg
Folic Acid 3.85 mg
Selenium 0.98 mg
Zinc 305.00 mg
Magnesium 0.60 mg
Manganese 89.00 mg
Calcium 260000.00 mg
Nicotinic Acid 279.00 mg
Pantothenic acid 133.00 mg
Choline Chloride 5800.00 mg
Sodium Chloride 14000.00 g
Amnio Acids - free-form (iKg)
Alanine 558.0 mg, Cysteine 57.0 mg,
Glyceine 304.0 mg, Histidine 133.0 mg,
Leucine 482.0 mg, Lysine 507.0 mg, Serine 291.0 mg,
Tyrosine 152.0 mg, Valine 374.0 mg, Proline 253.0 mg,
Aspartic acid 627.0 mg, Glutamic acid 1033.0 mg,
Isoleucine 348.0 mg, Phenylalanine 234.0 mg,
Threonine 272.0 mg, Methionine 88.0 mg,
Tryptophan 82.0 mg.
Ingredients: Calcium carbonate, Dicalcium phosphate, Potassium chloride, Sodium chloride, Dessicated liver, Ascorbic acid, Magnesium oxide, Isoleucine, L-Phenylalanine, L-Serine, L-Histidine, Dicalcium pantothenate, Choline bitartrate, Lecithin, Niacin, Ferrous fumerate, Zinc oxide, Copper sulfate, L-Glutamic acid, Riboflavin, dl-Alpha tocopherol acetate, Thiamine HCl, L-Arginine, Lysine, L-Leucine, L-Aspartic acid, Folic acid, Glycine, Manganese carbonate, L-Glutamine, L-Cystine, Pyridoxine HCl, Fish Liver Oil, L-Alanine, L-Threonine, L-Tryptophan, L- Tyrosine, L-Valine, L-Methionine, Cholecalciferol, Biotin, Cyanocobalamine, Kelp.
Guaranteed Analysis (minimum amounts)
Vitamins: Per Lb. (454 gm)
Vitamin A (Fish Liver Oil) 100,000 I.U.
Vitamin D3 (Cholecalciferol) 10,400 I.U.
Vitamin E (dl-Alpha Tocopherol Acetate )100 I.U.
Vitamin C (Ascorbic Acid) 1400.00 mg.
Folic Acid 48.00 Mg.
Vitamin B1 (Thiamine HCl )75.20 mg.
Vitamin B2 (Riboflavin) 124.80 mg.
Niacin 300.00 mg.
Vitamin B6 (Pyridoxine HCl) 30.40 mg.
Vitamin B12 (Cyanocobalamine) 3040.00 mcg.
Biotin 12,000.00 mcg.
Pantothenic Acid (Dicalcium Pantothenate) 849.60 mg.
Minerals and Electrolytes:
Calcium (Dicalcium Phosphate, Calcium Carbonate)
(21.2%) 96.00 gm.
Phosphorus (Dicalcium Phosphate) (10.6%) 48.00 gm.
Iodine (Kelp) (.0002%) 960.00 mcg.
Iron (Ferrous Fumerate) (.045%) 200.00 mg.
Magnesium (Oxide) (.26%) 1200.00 mg.
Copper (Sulfate ) (.045%) 200.00 mg.
Manganese (Carbonate) (.0077%) 35.20 mg.
Sodium (Chloride) (1.63% )7400.00 mg.
Zinc (Oxide) (.045%) 200.00 mg.
Potassium (Chloride) (1.76% )8000.00 mg.
Amino Acids: L-Glutamine 32.0 mg., L-Arginine 52.8 mg., Isoleucine 10.7 mg., Lysine 52.8 mg., L-Leucine 52.8 mg., L-Alanine 20.8 mg., L-Cystine 32.0 mg., L-Phenylalanine 10.7 mg., L-Serine 10.7 mg., L-Threonine 20.8 mg., L-Tryptophan 20.8 mg., L-Tyrosine 20.8 mg., L-Valine 20.8 mg., Glycine 42.7 mg., L-Methionine 20.8 mg., L-Aspartic Acid 52.8 mg., L-Glutamic Acid 148.8 mg., L-Histidine 10.7 mg.
Ingredients: 12 Minerals: Ca, P, Na, Mg, K, Cu, I, Fe Mn, Zn, Co, Se and 12 vitamins: A, D3, E, K3, B1,B2, B3, B4, B5, B6, B12 and Folic acid.
© The Tortoise Table, 2012. All rights reserved.