Lessons learned about water basics for poultry
As the single greatest input for producing meat and eggs, the importance of clean adequate drinking water has been long overlooked
By Susan Watkins, University of Arkansas
What is the source of drinking water standards for poultry? Who decided that poultry are tolerant of coliforms up to 50 colony forming units/ml or the maximum acceptable level of iron is .5 ppm? Surprisingly, most of our poultry water standards were adapted from the EPA’s guidelines for human standards by Extension Specialists like Tom Carter (North Carolina State University or Lionel Barton (U. of Arkansas) back in the 1980’s. But many of EPA’s standards are based on aesthetics, such as more than .5 ppm of iron or .03 ppm of manganese causes stains on clothing washed in the water. In the last 30 years, while poultry genetics have made huge strides in efficiencies, we have literally no new scientific data identifying toxic or harmful contaminant levels in the single most important nutrient our flocks consume, water. My ‘go to’ resource for assessing water contaminants is a 50-year-old book developed by the National Academy of Science called “Nutrients and Toxic Substances in Water for Poultry and Livestock”. Much of the information in this book is based on 70- to 80-year-old trials where birds received in their water, increasing levels of nutrients, like heavy metals, till symptoms such as poor weight gain or “death” were observed or in the case of many nutrients, no ill effects were ever observed. While that type of research is no longer acceptable as humane, it leaves us with the dilemma of wondering, as the birds have changed, have their water nutrient requirements or tolerances changed too? Water research for the sake of establishing nutrient tolerances just doesn’t have the ROI that feed or feed ingredient research has so even when a humane protocol is possible, there has been almost no push to revisit water standards for modern commercial poultry. Brian Fairchild at UGA did evaluate the iron tolerance of broilers back in 2005 and found birds were highly tolerant of levels up to 500 ppm. We also looked into the relationship between salt in the water and in the feed and found it was highly correlated and that manipulating dietary levels could compensate for some drinking water levels (Watkins, 2005). Beyond that, we are somewhat working in the dark when it comes to what is good or bad in the water for poultry.Fortunately, a 30-year career working with poultry drinking water has provided me with water wisdom that has come from visiting hundreds of farms, reviewing thousands of water analyses, assessing water systems and discussing with producers and live production personnel their observations on flock performance. This wealth of information and experience has provided insight into what birds need for drinking water.
Nutritionally birds are tolerant of most mineral contaminants with the exception of sodium and chloride. When sodium and or chloride levels are over 200 mg/l or (ppm), birds will experience loose droppings. When sodium and chloride levels are over 400 mg/l (ppm), birds can suffer depressed weight gains, increased feed conversions, dirty eggs and shell quality issues. Compensating for salt in the water can be achieved by reformulating the diet, removing the salt with reverse osmosis or dilution with another water supply.There is no “magic” filter for salt. The birds are tolerant of iron and manganese in the drinking water. I have seen water that was literally orange coming from the drinker line and the birds looked just fine. What modern poultry are less tolerant of is the microbes, like E. coli or pseudomonas, which thrive when the iron, manganese or sulfates are in the water. These pathogens may never show up, but my experience, particularly with our production strategy of “antibiotic free,” indicates that they usually do find their way into poultry farm water supplies and it is likely somewhere downstream of the sources. And once pathogens become entrenched into the biofilm, they can be the gift that keeps giving, flock after flock. Birds are tolerant of calcium in the water but the equipment is susceptible to scale build-up, which can reduce pipe volume and impair how drinkers function.Increasing combinations of magnesium and sulfate (>150 ppm) can cause loose droppings.Alkalinity in the water, mainly as sulfate or bicarbonate is a good thing, it adds buffering capacity to the water when found in ranges below 250 ppm. Higher levels can lead to bitterness that may back the birds off water consumption. Water that lacks natural buffering capacity in the form of alkalinity or minerals and is combined with a naturally low pH (below 4) is considered acid water and will cause the birds to self-restrict. Adding baking soda or soda ash can correct this. A good starting point recipe is one cup of baking soda dissolved into 5 gallons of water and then added at a rate of 1:128. The last point I have observed is that there is no “perfect” pH for birds. What pH adjustment product works on one farm with their water supply may not be ideal for another operation with different water parameters. pH is very dependent on the alkalinity or buffering capacity of water. This bicarbonates, carbonates or sulfates absorb the hydrogen ions that strong acids release when dissolved into the water. The more buffering capacity in the water, the more it “absorbs” the ions and prevents a pH change. While poultry are not overly sensitive to taste issues, they will back off consumption if water is bitter which can happen when too much bleach is added to water. So it may not be the amount of chlorine residual that is present, but rather the product used to achieve the residual. Is it fresh product? Has it been mishandled during storage and been exposed to sunlight or high temperatures? These are factors which deteriorate the chlorine residual so that more product may be necessary to achieve optimal sanitizing residual and the result can be bitter water. Many wise old poultry producers have pointed out the obvious. The birds will tell you what they like, just pay attention to how much they are drinking and if the flock is healthy, that amount should be increasing every day or something is wrong with taste or availability.
The most important thing we can do for modern poultry raised antibiotic free is provide “clean” water that is free of ANY coliforms, E. Coli and has less than 10,000 colony forming units of total bacteria and minimal amounts of mold and yeast. As an industry, we can be naïve about water contamination sources, overlooking open water injection sites, dirty filters or storage tanks, or what “nutraceutical” products are added. These are just a few of the contamination points we have identified over the years that can turn a great water supply into filth by the time it reaches the birds.In some cases, keeping water supplies clean is easy to achieve with little effort, while other operations must continuously work at water sanitation to protect the birds from being exposed to water borne pathogens like Bordetella. Implementing a consistent monitoring program is the most effective way to confirm water is the appropriate quality and can be as simple as pulling a water sample from the drinker lines and testing for total bacteria and correlating it to a sanitizer residual level.
Poultry, even day old chicks, prefer cooler water temperatures and birds need adequate water quantities to achieve their potential. This means preventing water flow restrictions from occurring in filters due to sediment build-up, pressure reducers, regulators, injectors and water lines. Confirm, at least on an annual basis that water supplies, including the drinkers, provide adequate flow throughout the life of flocks. Even a slight restriction due to hardened regulators or mineral build-up can train birds to regulate their intake and cause them to fail to reach their genetic potential of weight gains and feed conversions because there just wasn’t enough water present in the crop to adequately soften feed for optimal digestion.
As the single greatest input for producing meat and eggs, the importance of clean adequate drinking water has been long overlooked. It isn’t easy to determine a consistent ROI optimizing the quality and quantity of water, but years of experience identifying and correcting water issues has provided me with enough evidence that it matters. As an industry, we are overdue to make drinking water a higher priority. Companies with multiple production sites are well positioned to develop their own standards based on correlations between bird performance and water quality and quantity parameters. The first step starts with system assessments and sampling. Our modern birds deserve it.
Susan Watkins is Distinguished Professor, Emeritus with the University of Arkansas.
