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Calcium in the diet of reptiles – role and supplementation

Calcium in the diet of reptiles and its supplementation are key elements of proper reptile nutrition. They help to prevent metabolic bone diseases which are the most common effects of a lack of proper calcium supplementation.

What is the function of calcium in the diet of reptiles?

Calcium in the diet of reptiles has important functions in many metabolic processes. Among other things, it is responsible for muscle contractility, nerve conduction, blood clotting, cell membrane permeability, enzyme activity, and bone metabolism. In the life of every reptile, there are several stages during which it is very important to provide the right amount of calcium in the diet:

  • growth – when a large amount of calcium is needed to support the formation of the skeleton as other tissues grow;
  • maturity – with sexual maturity, the need for calcium decreases as the growth rate slows down; it is also worth noting that reptiles grow throughout all their lives, but this growth becomes less intensive when they reach sexual maturity, and eventually minimal;
  • reproduction – during this period, females need additional calcium for the construction of egg shells (too little calcium in the diet causes the body to give up calcium from the bones).

How much calcium do reptiles need?

According to many authors, the optimal dietary calcium content is 1-2%. All reputable reptile food companies declare this value in their products. These data are based primarily on studies of the nutritional requirements of hen chicks and other poultry and on many years of reptile observation. The calcium to phosphorus ratio is also important. Optimally, it should be 2:1 (calcium : phosphorus). This is the ratio obtained in blood serum analysis of most vertebrates.

When the ratio is reversed in the blood serum in favor of phosphorus (due to a decrease in calcium), the body seeks to achieve adequate levels by recovering calcium into the blood plasma from calcium-containing tissues, especially bones. Unfortunately, the calcium recovered in this way is lost with urine. If we then fail to supply the body with adequate amounts of calcium, this condition will lead to metabolic bone disease (MBD).

What are the sources of calcium for reptiles?

The most popular dietary source of calcium is calcium carbonate. It is characterized by relatively high calcium content (about 40%), but its absorption in the intestines is poor. Compounds such as calcium lactate (17.5% Ca), calcium gluconate (9% Ca) or calcium citrate (24% Ca) contain a lower percentage of calcium than carbonate. However, their absorption potential, or its availability to the body, is much greater.

The best option is to use products that contain diverse sources of calcium and at the same time do not contain vitamin D3. They can be administered with each meal without the risk of overdosing vitamin D3.

One of such a product is Tropical Vigorept Mineral. It is a modern mineral product that does not contain vitamin D3. Thus, it can be used daily without the risk of vitamin overdose. It effectively prevents rickets (MBD) in reptiles and amphibians, deformations of turtles’ shells as well as other dangerous effects of calcium and phosphorus deficiency. It contains various sources of calcium, including organic calcium from Lithothamnium calcareum algae with high bioavailability potential. Lithothamnium calcareum is also a source of natural, highly absorbable magnesium and other essential trace elements. Proper mineral-vitamin balance improves appetite, vitality, condition and ability to fight against infections.

How to calculate the right dose of calcium for reptiles?

To calculate the necessary calcium intake for reptiles, you need to know the percentage of calcium in the product. It you use Tropical Vigorept Mineral, which contains 29% calcium, in order to achieve 1-2% calcium content in the food, you must give 6 g of the product per 100 g of food.

Example of calculating calcium intake for a reptile

A standard serving of greens, which we give to the animal, weighs about 25 g (you can check it on a kitchen electronic scale).

We know that for every 100 grams of food, 6 grams of formula containing 29% calcium should be given. We need to calculate how much of the product should be added to 25 g of greens:

25 g x 6 g / 100 = 1.5 g

In this case, 1.5 g of Vigorept Mineral (1 level teaspoon/2 ml volume included in the product) per serving of greens.

How to give calcium to reptiles?

Plant foods should be sprinkled with the product and stirred thoroughly. Insects for insectivorous animals should be put into a small box or bag. Then sprinkled with the product and shaken gently several times so that the powder covers the insect bodies. When you give the product to your pet the first time it’s a good idea to weigh the standard portion of food beforehand to calculate from the proportions how many grams of the product should be given.

Insects with calcium for reptiles

Special attention should be paid to preventing calcium deficiencies in the diet in times of increased demand (growth, reproduction) and during convalescence.

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

In general, there is little risk of calcium overdose without excessive amounts of vitamin D3. However, too much calcium given at once can affect the efficiency of digestion by neutralizing stomach acids and raising the pH in the stomach, which is not desirable. That’s why don’t give reptiles calcium in the form of mineral products just to stock up. And never try to quickly make up for previous negligence and deficiencies in supplementation.

Large doses of calcium will not produce the same results as smaller amounts given at each feeding. If extremely large amounts of calcium are served at one time, there may be a risk of “concreting” the lumen of the digestive tract, especially in small and delicate species. Insects should be lightly sprinkled with mineral products, not coated with it. If you provide too much vitamin D3 in the diet, there is a risk of excess calcium being deposited in the tissues (and it should not be deposited there).

Prevention of metabolic bone diseases in reptiles

I would like to point out again that several factors are of greatest importance in the prevention of metabolic bone disease in reptiles. First and foremost, provide the right environmental conditions in the terrarium. Then ensure varied diet based on high-quality foods and reasonable supplementation with mineral and mineral-vitamin products.

Dawid Krótki


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