But what are electrolytes and why do they have such an important function for the organism?
Here you can find a detailed description.
Generally electrolytes are electrical and conductive substances. Often they are called minerals and are essential for the function of the whole organism. A functional organism and health can only be guaranteed if there is no lack of any electrolyte. They cannot be produced in the organism so that horses need to ingest them by the food. All body fluid consists out of water and electrolytes. Due to this one can call them “transporter” and they guarantee that all substances get transported to their respective area in the body. Referring to this the body fluid regulates all processes concerning the growth and the food of a horse. Furthermore they are located inside the cells (cytoplasm), muscles, heart and intestinal wall and everywhere they provide functioning biochemical processes.
The fact that electrolytes are located at all important organs of the organism and guarantee the respective function already indicates the danger of a possible lack. It can cause a real health restriction if a horse does not provide enough electrolytes. Especially horses which get trained a lot have a higher need of electrolytes. With the sweat they also lose a lot of electrolytes what easily ends in an undersupply. A further reason for the lack of certain electrolytes is the over-cultivation of many fields in Europe (only important if you use fodder from Europe!). This is a real problem because the fields and therefore the harvest do not offer enough of natural minerals. Fodder which comes from these regions naturally does not have enough of electrolytes what can cause an undersupply.
The most important electrolytes in the organism are sodium, potassium, calcium, magnesium, chloride, phosphorus and hydrogencarbonate.
For all these minerals experts recommend to feed a daily dose. With a blood screening you can check the dose of each mineral in your horse. The blood screening is really helpful because through this you can see if your horse has a lack or an oversupply of a certain mineral. If you find out that your horse has a lack of an electrolyte you need to consider the effects of feeding additional compounds (e.g. special fodder with electrolytes). Most often these special types of mineral fodder do only consist out of common salt, dextrose and vitamin C. Indeed these substances are not really effective but very expensive and mostly the manufacturers make benefit from it. According to this a lick can be a good alternative. You can place it in the box of the horse and it does not only save money but also offers enough of sodium and potassium.
For horse owners and riders it may be really helpful to have an overview of the most important electrolytes. Below you can find a description.
In colloquial usage sodium is called salt. However there are two different types of salt: the salt for us humans (which also offers a substance called fluoride) and the cattle lick. Therefore the salt that we humans eat is not the same salt that our horses need. Sodium is responsible for the function of the cells but mostly it regulates the water balance in the organism. Water and salt influence each other so that a lack or an overdose of salt also affects the water in the body. Due to this an overdose of salt means that the organism cannot ingest enough water anymore. In some cases this can even end in a dehydration. In opposite to this a long termed lack of salt can cause damage of the brain and in worst cases even an epileptic seizure. If horses often get trained so that they sweat a lot their need of sodium becomes higher. Consequently the recommended daily dose of sodium depends on the physical performance. Horses with only a little physical performance need 27 g, horses with a normal physical performance need 43g and horses with a high physical performance need up to 85 g (all data relate to the daily dose; there is a tolerance up to 5 g more or less). If horse owners want to guarantee an optimal supply of sodium they can place a lick in the horses’ box.
Potassium is a mineral and in a chemical compound with chloride it becomes salt. Generally there are two types of salt: the first one results from the chemical composition of potassium and chloride and the second one from sodium and chloride. Due to this there are differences between salts. Consequently a lick does not provide potassium so that horse owners need to feed it in another way. The main function of potassium is the regulation of the Osmotic Pressure. This means that there is balance between the in- and outside of the cell so that there is the same pressure on both sides. This balance guarantees the stability of the cell. Furthermore potassium transfers nerve impulses and regulates the rhythm of the heart and the work of the muscles. Moreover the mineral is responsible for the enzymes which participate at the production of glucose (sugar). Normally fodder guarantees the need of potassium. Nevertheless horses which offer much physical performance lose a high dose of minerals (they leave the organism together with the sweat). Then horse owners must feed additional electrolyte compounds. A vet or nutritionist can help you to find the best fodder (we recommend to contact a vet or nutritionist anyway).
You can find calcium in teeth and bones. Therefore bones save calcium what offers great advantages: if there is a lack in the organism bones are able to set free little doses of calcium so that they can participate at important metabolism processes in other parts of the body. This separation process of the bone is really normal because humans and horses have a dynamic skeleton. This means that bones are able to reproduce theirselves: every day they separate tiny parts but also produce new ones. As a result the bone keeps its size, is more robust and additionally with every separation also little doses of calcium get releases so that they can be used for other processes in the organism. A bone consists out of 30 units of calcium, 14 units of phosphorus and 1 unit of magnesium. Further functions of calcium are the excitation of muscles and nerves as well as the storage and provision of glucose. Moreover it is involved in the cell division and the activation of enzymes and hormones. A lack of calcium can cause great damages, especially for young horses which still grow. In this cases the bones cannot grow enough and do not become robust. In opposite to this old horses suffer from an overdose because this can cause problems with the kidney.
In the organism this mineral is in a chemical compound with sodium what makes it to a special type of salt. Together with potassium it is responsible for the Osmotic Pressure. Therefore it guarantees and is essential for the stability of the cell. In connection with sodium it is responsible for the production and transmission of nerve impulses. Additionally chloride (in a chemical compound with hydrogencarbonate) participates at the acid-base balance. You can find it in gastric acid where it helps together with other enzymes to dismantle proteins. Therefore chloride is important for the digestion. Horses which offer a great physical performance need a high dose of chloride because it is responsible for the tissue and the muscles (these horses need the triple dose!). You can easily see that the daily dose is dependent on the physical performance. The recommended daily doses are: 80 g for horses with a little physical performance, 103 g for horses with a normal physical performance and up to 143 g for horses with a high physical performance. A lick provides chloride so that you can easily guarantee the daily dose.
Hydrogencarbonate is essential for the acid-base balance. This mineral has great alkaline effects so that sometimes it is called an “acid buffer”. Therefore we humans take hydrogencarbonate if we suffer from heartburn. In a chemical compound with sodium, calcium and magnesium it has anti-inflammatory effects so that hydrogencarbonate is important for the whole organism.
Mostly you can find magnesium in the muscles and bones where it is responsible for the functionality. Besides, this mineral participates at more than 300 metabolism processes in the whole organism. Especially horses with a high physical performance can easily suffer from a lack of magnesium. Calcium and magnesium are responsible for the function of muscles: at first calcium tightens the muscles before magnesium guarantees the relaxation. Consequently trembling in the legs of the horse after an exhausting training is a hint for a lack of magnesium. Moreover the stability of the bones depends on the electrolyte magnesium. As already explained horses have a dynamic skeleton so that in case of an undersupply bones can set free some reserves of magnesium and calcium. Nevertheless this is no long-termed solution so that a long period of an undersupply of magnesium will have negative influences on the quality of the skeleton. This means that the skeleton loses its stability what easily causes fractures (this can have immense negative consequences for horses with a high physical performance, e.g. horses which participate at competitions). In general a lack of magnesium has much more negative influence on the stability of the bones than a lack of calcium. According to the structure of bones (30 units of calcium, 14 units of phosphorus and 1 unit of magnesium) the daily dose of magnesium needs to be in balance with the dose of calcium. A long-termed lack of magnesium can cause renal failure.
Independent of the organism phosphorus is one of the most important electrolytes. Together with magnesium and calcium it is a component of bones. It has great significance for horse breeding because this electrolyte is a component of the DNA and RNA so that it influences the transferability of genes. It participates at the energy metabolism inside the cells and is needed for high physical performance. A further characteristic of phosphorus is the fact that you need to feed it in a special proportion to calcium. This proportion is between 1,5:1 and 2:1.
Conclusion: In general all electrolytes have an essential significance for the organism and especially horses with a high physical performance can easily have an undersupply. Furthermore you have to consider that some electrolytes influence each other and need to be fed in a certain proportion (e.g. calcium and magnesium, calcium and phosphorus). If you have a horse with a high physical performance we recommend to contact a vet or nutritionist. They will check your horse and propose the right daily dose of electrolytes.
All data concerning the daily dose of electrolytes refer to a normal horse with an average body weight of 600 kg.