Business & Policy
Managing Turkey Water Quality
By Karen Dallimore
There may be a thief in your barn, robbing your poultry
By Karen Dallimore
There may be a thief in your barn, robbing your poultry of optimum
growth and performance. It’s not your typical suspect when your birds
aren’t performing their best but maybe it should be.
There may be a thief in your barn, robbing your poultry of optimum growth and performance. It’s not your typical suspect when your birds aren’t performing their best but maybe it should be.
It’s your water, and although you may think you may be sanitizing it properly, it still may be worth a closer look.
Are your birds healthy and performing up to par? Is your flock performing evenly?
If the answer is no, your water may be the culprit. Turkeys consume twice as much water as they do feed. Effectively sanitized water is critical not only for your birds to drink but also for sanitizing hatching eggs, disinfecting barns and equipment and for consumption by farm workers.
Younger birds are more susceptible to most pathogens, but water quality is critical for any age or type of bird. Any time the birds are exposed to pathogens the immune system is triggered and feed energy is diverted from growth to defense.
The most common pathogens that can affect water quality are E. coli followed by Bordetella (coryza) and Pseudomonas. Many farms routinely test their water for bacterial levels (coliforms) and mineral and inorganic elements such as nitrate, sulphate, iron, chloride, sodium and calcium.
Chlorine is typically used as a sanitizer although hydrogen peroxide can also be used. These chemicals are known as oxidizing agents: they bind with the pathogen, destroying it by causing its cell membrane to become destabilized and leaky.
But if you’re adding chlorine already, isn’t that enough? Maybe not. The chlorine must be in the right chemical form and in an optimum environment to work effectively.
Many producers believe that if you can smell the chlorine that sanitization is adequate. All it means is that there is chlorine present but it doesn’t mean that it is working effectively. What you are detecting with your nose is in a form called chloramines. These are formed when chlorine binds with organic material, which means that although the chlorine is present it is no longer available to attack contaminants.
Water Quality Testing
Many producers use chlorine tester or pool type test kits to measure free chlorine levels in the water. These tests measure both hypochlorous acid (HOCl), which kills bacteria on contact, and hypochlorite ions (OCl), which require a prolonged contact time to kill bacteria. For practical purposes it is the hypochlorous acid we’re looking for, since it is impractical to hold water in retention tanks for long enough periods of time for the slower-acting hypochlorite ions to kill bacteria.
Assuming that you do have enough chlorine available and it’s in the right chemical form, you also need to know that the environment is right for the chlorine to work properly. There are two easy tests that can be performed on farm to tell you this: one is the pH, and the other is the oxidation-reduction potential, or ORP.
Let’s say the test result show chlorine at 3 ppm: is that the fast-acting (hypochlorous) or slow-acting (hypochlorite) form of chlorine? To answer this you need to know the pH of the water. At a pH of 6.8, 96% of the free chlorine is hypochlorous acid. If the pH is 8.0, only 22% of the free chlorine is in this fast-acting form.
This explains why, for many years, producers who were theoretically using adequate levels of chlorine were still experiencing difficulties with pathogens such as Bordetella. If the pH was high the chlorine was not in the proper form to kill the pathogens.
Oxidation Reduction Potential
ORP stands for Oxidation Reduction Potential. It is measured in millivolts (mV). The binding of the chlorine or other sanitizing agent to a pathogen depends on a transfer of electrons. An ORP of 700 mV is ideal for this reaction to take place.
The ORP reading allows you to find the optimal balance between pH and free chlorine for your water, allowing you to use the minimal amount of chlorine to do the job. Too much chlorine will cause corrosion of the water system. If the ORP is high the amount of free chlorine can be reduced; if the ORP is low the pH and chlorine levels need to be re-balanced for optimum performance.
Measuring ORP can also be a good way to determine the thoroughness of cleaning and disinfecting procedures between flocks. If the ORP in the waterlines at the front are good but low at the back of the barn, it means that there is organic matter tying up the chlorine along the way. Repeat your cleaning procedures rather than relying on superchlorination to do the job.
An ORP meter costs about $90 to $120 and a pH meter about the same. Combination ORP/pH meters are available for about $200, and you may also need to purchase ORP calibration solution and pH standard solution to perform monthly calibration checks. The glass electrodes should also be cleaned every month, more often if the water is high in minerals.
Dr. Helen Wojcinski, Science and Technology Manager with Hybrid Turkeys, outlined the following scenario to explain the importance of water quality.
At five weeks of age, a turkey flock that is brooded on the same farm was split and moved to two different grow out farms a few miles apart, Farm A and Farm B. Both farms were well managed and the feed was the same, but the birds at Farm A became loose, the litter got wet and caked over, the footpads became affected and there were more leg problems. No amount of ventilation seemed to be adequate. Litter costs were higher, ammonia levels were high due to the wet litter and airsac condemnations were high. Treatment with tetracycline antibiotics was not very effective.
On Farm B, the birds got a little loose on arrival but straightened out quickly, and there were no other problems. Any minor airsac issues responded well to tetracycline.
Instead of looking for a virus as the culprit, Dr. Wojcinski looked at the water first.
Farm A showed high levels of minerals and inorganic elements. Sulphates were three times normal, chlorides four times and the sodium was double, all of which contributed to the looseness in the turkeys.
Farm B had slightly high levels of sulphates only, which accounts for the initial looseness, but the flock quickly adapted.
The pH at Farm A was alkaline at 8.1 as compared to a pH of 6.8 at Farm B, which meant that the same level of chlorination would not provide the same level of sanitization effectiveness. This resulted in high bacterial levels in the water at Farm A.
“The water on Farm A was so bad that the grower installed a reverse osmosis system. This is expensive and requires a large volume of water but the result was that flock performance improved dramatically,” explained Wojcinski, who said that the grower never realized how much of an impact water quality could have on his flock.
Wojcinski added, “remember any time you add anything into the water, i.e. antibiotics, vitamins, electrolytes, competitive exclusion products, probiotics, yeast products, etc., you will affect the ability of chlorine to do its job.”
She suggests analyzing water twice a year as part of a routine and not necessarily just when a problem is suspected. She also suggests that producers should check pH, free chlorine or ORP as frequently as necessary to ensure that the water sanitization system is effective. Regular testing would allow a farm to document a baseline, which can be a useful tool to compare performance.
Hybrid Turkeys measure ORP on all of their farms, and Wojcinski believes that ORP testing, while not yet commonplace, is a valuable tool and a worthwhile investment. After all, she says, how much does it cost not to know whether you are sanitizing your water effectively?
1 Oxidation Reduction Potential (ORP): A New Tool for Evaluating Water Sanitation. Hybrid Turkeys. www.hybridturkeys.com
2 Effective Chlorination. Hybrid Turkeys. www.hybridturkeys.com