Animals that are stressed or sick usually avoid feed, but they do drink water. Increased water intake is observed even before the onset of fever in several outbreaks, and this has been used as a tool in aiding animal management. It is a well-known fact that water administration of medicinal compounds is more efficient and can be more precise than using the same drugs through feed. Water, however, can be a useful medium in administering not only medicinal compounds but also several nutrients that can sustain and promote animal health and wellbeing.
- Antimicrobial compounds
Organic acids, like citric acid, for example, are often added in the drinking water to combat pathogenic bacteria. This is a useful practice in weaned pigs. Increasingly, other compounds are finding their water-soluble forms, with prime example being essential oils (or plant extracts) that are essentially hydrophobic.
- Heat-stress compounds
Adding citric acid (again) and (or) sodium carbonate in drinking water aids poultry during heat stress conditions. The exact proportions differ among experts, but the end result is that such compounds are best used through the water system and not through the feed.
Several peptides (mainly from fish) are being marketed in a water-soluble form with results that point to increased animal immunity. Indeed, older studies have shown peptides from fish and milk can have an immunostimulating effect. Other nutrients often used in water nutrition applications include sugars and vitamins for animals.
There are definitely more nutrients and compounds that can be used, and I know a few more that are being tested. The whole idea is very interesting, and as most farms already have a water medication system, it costs nothing extra to experiment with this practice.