Water represents 80% of the weight of a newborn piglet and is the most essential of all nutrients. Yet, in many nutrition audits and routine work, swine professionals overlook to assess the quantity and quality of water delivered to pigs, leading to misunderstanding and mismanagement of this important resource.
Therefore, water is known as "the forgotten nutrient." However, there is increasing evidence that we should not continue to ignore the role of water in pork productivity and health, and in environmental sustainability. Therefore, a workshop at the Allen D. Leman Swine conference drove from the knowledge of experts in swine nutrition and pork production to answer basic and applied questions about management of water for maximizing pig performance. Here, the main topics discussed are highlighted.
Many ask why water is so important and how much pigs need. These questions were answered by John Patience from Iowa State University, who explained that there are multiple reasons why water is essential.
For example, water can absorb a lot of heat before it starts to get hot. Therefore, water is essential to thermal homeostasis of pigs, and all living species, because when evaporated water removes about 540 calories per gram, this value is almost 10 times greater than other solvents. In addition, metabolic and physiological events require a medium for transfer of nutrients, chemical reactions and elimination of waste products.
Water serves all these roles quite well. A 45-kilogram pig may drink about 5.5 liters of water per day. The greatest factors contributing to water requirement and water retention are the capacity of pigs for muscle deposition and feed intake. A practical approach to estimate the requirement of water is to use a water-to-feed ratio 3 liters per kilogram of feed consumed at thermoneutral conditions. Because estimating the exact requirement is difficult, dynamic and complex, we should supply water and allow animals to drink as much as they need (ad libitum).
Yet, if abundant, it may not mean that water will cover all desired functions, because quality matters. It is often that swine veterinarians, nutritionists and caretakers question the quality of water supplied to pigs and the impact of poor water quality on difficulty to raise nursery pigs.
Therefore, Brigit Lozinski at the University of Minnesota was charged with the task of identifying sources of water within Minnesota based on quality. Lozinski conducted surveys and sampled and analyzed water to assess a wide range of quality attributes. She selected two sources of water with high quality and one source with low quality. She then provided these sources of water to newly weaned pigs in a performance experiment. She observed little if any difference in growth performance and measurements of gut barrier function, and in other physiological and immune parameters. She showed that under optimal management conditions, pigs are capable of adapting to drinking water of diverse composition.
Water is a useful vehicle to deliver medications, such as antibiotic treatments to pigs, at critical periods such as at receiving newly weaned pigs or during disease outbreaks. There is substantial variation in the dose of actual medication among pigs within a pen, pigs among pens and among barns. This variability means that some pigs may receive less than the optimal dose of the medication or that other pigs will receive an excess. Steve Little, at the University of Melbourne in Australia, recommends a nine-point guideline for best practices when medicating pigs via water.
- Consider the design of water pipelines
- Maintain optimal flow rate at all drinkers
- Test regularly for water quality
- Use an appropriate antimicrobial
- Calculate the dose using actual number and body weight of pigs that will be treated
- Deliver the medication according to pigs' seasonal drinking patterns
- Use of adequate dosing pump
- Use of diluted stock solution to ensure a high pumping rate
- Use a stirrer to mix the solution during dosing
Managing water to maximize pig performance was the last topic discussed at the workshop. Nat Stas, Pig Improvement Co., delivered a comprehensive set of recommendations for making sure that water is available on a day-to-day basis and that barn managers can troubleshoot when issues arise. The number of pigs per drinker, the height of the drinker and layout of drinkers within the pen are factors to consider when setting the drinkers in the barn. Water flow rate that is measured at the pen level is an essential yet often overlooked factor to adjust during pen preparation in receiving young pigs and through the course of the stay of pigs in the barn.
In summary, various aspects of the importance of water in pig performance and production were mentioned during the workshop, with special emphasis on barn level applications.