Water is a basic and an essential requirement for a horse. It is the most important form of nutrients bar none, providing many minerals. Water is the vector of life and bestows health, helping a horse's body with many things such as expelling toxins, lubrication of joints and maintaining the thermoregulatory system to name a few. Therefore, it's essential to provide your horse will clean, safe water. Considering these things and an average size horse will drink between 4 to 10 gallons of the stuff per day. Nevertheless, it’s complicated how much water a horse needs and it depends on muscle mass, food type, exercise, environment and even food quality, however, without it horses will die within a matter of days. A horse could get most of the water it needs from grass, yet it could get quickly dehydrated through exercise, extreme conditions or thermoregulation difficulties or diarrhoea. When a horse is fed fibre like hay it will need more water because it moves into the hindgut from the intestinal tract, and would cause the horse to drink more. The two main testable symptoms of dehydration are a loss of skin elasticity and slowed capillary refill. Which can be tested on a horse by either a pinch test at the point of the shoulder or a capillary refill test with a thumb on a horse’s gum.
As I have just said it’s important to provide your horse will clean, safe water, this doesn’t sound difficult, but even tap water can be contaminated by lead pipes or bacteria. Only a short while ago people in Lancashire had to boil their water for at least a month because of Cryptosporidium which is a really nasty parasite. A horse may be put off by the taste for example if the water contains too much of a mineral like iron or calcium, where a long-established example of this would be sulphur. Add to this frozen pipes or water container and a horse sweating under too many heavy rugs and you have a cocktail for disaster.
The best water for your horse is from a natural origin, a spring or a well tapped into a natural source. However, there is no such thing as safe water. Rainwater is usually good, although you have to watch containers for contamination, but at least it is under your control. Streams or rivers are usually a reasonable water source and are a better option than a pond or a groundwater well, yet there is always a risk of contamination from industrial spillage. Where ponds, groundwater wells and streams are more likely to be contaminated with fertilisers and herbicides running off farmland making their way down with surface water. Personally, I would use tap water before using or digging a pond unless I owned the land around it. Tap water does not provide a good mineral source because of other chemicals in tap water inhibits mineral uptake. It also contains antibiotics from unfiltered antibacterial hand washes, which affect hindgut microorganism populations. It is advisable to test your water source, especially if it’s a pond or your horse stops eating or drinking or there are any unpleasant smells. It will need its pH level testing and for sulphates and high mineral content like copper or iron. If it appears cloudy test for pesticides, bacteria and algae. Also, do not forget that roads are salted during the winter and can push too much sodium and chloride into your groundwater. Manure piles are another problem where nitrates can seep into your water as well.
Minerals are normally divided into two categories macro-minerals or major minerals and micro-minerals or trace minerals. Where major minerals are needed in the diet daily and trace minerals are only needed in tiny amounts. Some minerals can also be described as colloidal minerals, however, this is basically a delivery method rather than a type. Minerals can be crushed rocks and they are a crucial part of a horse's diet. They help in the digestion of fats, proteins, carbohydrates and help transport oxygen in blood as well as being an obligatory part of every enzyme and fundamental to some amino acids, hormones and vitamins. Minerals are often linked to other minerals and if one or the other aren’t present then it will affect the absorption and utilisation. A good example would be calcium and phosphorus where both are needed and at least as much calcium as phosphorus for the desired effect.
Chelating is used to bind minerals to amino acids which up the absorption rate of minerals astronomically and is used by some food companies. When I first read this I thought brilliant and then on second thoughts there we go again interfering the natural process. Really the best way to obtain vitamins and minerals is via our horse food and water.