Water quality is critical in pig health 
and productivity

By Peter Bedwell

On February 7, the first keynote speaker at the virtual Australian Poultry Science Symposium 2022, was Professor Susan Watkins (University of Arkansas) a leading US based expert on water quality in poultry production.
So how does that apply to pig production?
Apart from the difference in species and growth cycles, maintaining good water quality and adequate supply levels to pigs and poultry is vital to both species.
Key concepts of maintaining water quality included “paying regard to mineral contaminants and calcium and its effects on drinker lines, the drinkers themselves and cool cell pads if they used in the sheds”.
“There is no perfect pH for performance,” Prof Watkins said.
“Water quality guidelines have traditionally been based on human standards for common contaminants based on aesthetics, not health. There is the exception of heavy metals like lead, arsenic and copper.
“Proven points in water quality include controlling to prevent microbial contamination, regular monitoring of the drinker system and providing livestock with an adequate quantity of water in a timely manner. Temperature control is also important,” she said.
“Water quality can be a source of performance issues, including FCRs.
“Acknowledge that water deserves careful attention as it is the number one nutrient input.
“Water supplies are dynamic as multiple factors influence quality so quality can change. Water supplies are unique and the source, mineral content, pH and microbes all affect quality.
“Operations differ from farm to farm. Storage, distribution, injection technology and location as well as drinker design and product usage, all play a part in quality variability.
“Water promotes life that is both good and bad as pathogens continue to change and adapt as they take advantage of water delivery systems,” she said.
“Surface water supplies are the most vulnerable so document quality testing for minerals, pH and bacteria,” Prof Watkins advised.
“Implement a water system assessment program and ‘inspect what you expect’.
“Is your storage clean, or has it been cleaned, is sediment present and are your injectors for chemicals or 
vaccines working correctly and meeting demand?
“Is your water system sanitation cleaned regularly and daily water product usage measured?
“Filters and injection points are critical areas. Are the filters clean as sediment build up invites microbes and dirty filters block flow to drinker points?
“It is important to verify injection technology and to confirm that injectors add products uniformly and do not restrict water flow.
“Assess if injectors dump or bend and do injectors in your drinker system cause products to fight each other.”

Is there enough water?
“The RainWave product is available at Amazon.com for around $35 USD and can be used in-line to check flow by litres and confirm injector accuracy,” Prof Watkins said.
“Consider going inside the water system with affordable inspection cameras.
“Conduct water tests at least annually to assess mineral content and pH. Test at the source post treatments, filtration and sanitation.
“Microbial testing for total bacteria E.coli coliforms, yeast and moulds and as needed, assess product impact on water quality and evaluate the efficacy of disinfectants.
“Collect samples from source and drinkers for total bacterial loads using an inexpensive quality assurance test. Assess how the various products you use to achieve good water quality actually achieve that aim.
“Control biofilm as clean pipes can rebuild biofilm in 3-5 days and if E. coli is introduced into the water it can incorporate into the biofilm.
“Problems can be introduced but consistent water quality maintenance reduces the risks that opportunistic pathogens create.
“Take action. Use test results to assess strengths and weaknesses and develop programs that compliment the water source and invest in water quality technology.
“If systems are dirty, implement a cleaning program.”
On the topic of water system cleaning essentials, Prof Watkins stressed that regular cleaning at clean-out was important.
“The right concentration of an effective cleaner left for the correct interval is the key to success,” she said.
“Cleaning the whole system is essential and there are lots of great products for cleaning and sanitation, so carefully document which ones work best for your operation and collect line swabs pre and post cleaning.
“Flush the system post cleaning with a sanitiser that is palatable to the animals and helps to kill any bugs that survived the line cleaning step.
“Chlorine is still an effective sanitising tool but to optimise chlorine effectiveness, a pH range of 4.0 to 7.0 is desirable.
“Use only clean water with no turbidity and clean the system to remove biofilm slime and make sure that adequate exposure time is used.
“Always use a fresh chlorine product that has been properly stored (away from sunlight) and injected into the system.
“Chlorine abuse or misuse results in challenges breaking through,” Prof Watkins warned.
“How much chlorine product is too much or how much product is added to the water to achieve the desired chlorine residual?
“Chlorine is stabilised at pH 11 and this requires sodium hypochlorite and calcium hypochlorite. Both of these result in taste bitterness – the more that is added, the more bitter the water.
The recommended product concentration is 6% vs 12%. The stronger concentration ultimately requires less product to achieve sanitiser goal.
However, length of storage, exposure to sunlight and warmer temperatures all decrease chlorine strength.
“Monitor and document, as consistent monitoring assures sanitiser residual is present and documentation is 
essential for correlating performance with water sanitation.
“Any product can work or fail, so verify by regularly measuring total bacterial levels.”
Another warning Prof Watkins issued, concerned the overuse of organic acids.
“Increased organic acid use for gut health and food safety can result in water system slime issues. Conduct disinfectant sensitivity tests,” she recommended.
In concluding her paper, Prof Watkins stated that “the use of organic acids without sanitation can lead to slime challenges and clogged drinker systems.
“More evaluation is needed to determine the conditions which promote this incidence but currently we know that if water is susceptible to pseudomonas, there is a risk.
“Sanitiser sensitivity is a tool to determine what is best for your operations,” she said.
The Watkin’s Water Recipe is as follows:-
• Accept that water can create risks for animals so identify minerals, pH, bacteria, yeast, mould and any other contaminants.
• Prepare a strategy to reduce or eliminate challenges and utilise a daily water sanitiser best suited for your operation that is compatible with water source, easy to use, easy to monitor and cost effective.
• Monitor and verify that the 
program works and if you, the producer believe in a well prepared water 
program, your team will too.

Simple things that cause problems
Pork Journal discussed drinking water issues with Dr Peter McKenzie who runs his Health Through Stealth programs on a number of farms that we have reported on in recent times.
He identified some simple things that can cause problems in water quality and delivery of adequate water supply.
“The first is redundant drinker lines that can hold contaminated water that ends up by affecting the whole water supply system in sheds,” he said.
“As farms have expanded, water supply lines have become more extended over time.
“Also, the lack of non-return valves in the system results in further contamination.
“As shed sizes have grown, extended drinker lines can lead to a fall off in water pressure and thus supply at extremities.
“One solution is to bring the main water supply to the centre of the shed, rather than just one end. This equalises the overall pressure and thus maintains a consistent water supply.
“Drinking systems in pig production not only need to supply good quality water but also have consistent and reliably uniform delivery throughout the system.
“The development of vaccine delivery through drinking water systems requires a uniformity of flow to ensure equal delivery of water vaccines to the pig population on farm.
“Similarly, precise dosing of medication to counter any disease outbreak is essential not only for animal welfare but also to maintain good on-farm anti-microbial resistance stewardship.
“Apart from those considerations, accurate and effective in-line medication equipment is a critical item in both in-water vaccine and medication strategies.”
Dave Roberts of Huntley based Think Livestock, whose business has grown from providing vaccination equipment into the area of water quality maintenance, including highly accurate delivery of vaccines, medications and water sanitising products.
His Select Doser is highly regarded in both pig and poultry production for accurate delivery of in-drinker water agents.
When asked by Pork Journal about the occurrence of slime developing in drinker lines as a result of excessive levels of organic acids being included in drinker systems, he responded by pointing out that “if accurate inclusion rates, according to manufacturer’s 
recommendations were adhered too, the risk of creating slime was significantly reduced.
He also added that “the use of quality organic acids to maintain a well sanitised drinker system was a vital 
element in maintaining water quality”.
He also agreed with Prof Watkins over the need to ensure products like chlorine were stored correctly (out of direct sunlight for instance) and used within ‘use by’ requirements.
There has been much research conducted into water quality and in water medication and vaccine delivery in 
Australia, and particularly in recent times.
Research conducted by Stephen Little and Helen Crabb and others from the Asia Pacific Centre for Animal Health, Faculty of Veterinary and Agricultural Sciences and National Centre for Antimicrobial Stewardship, University of Melbourne was released in May 2019 entitled ‘Water medication of growing pigs: sources of between-animal variability in systemic exposure to antimicrobials’.
“On many Australian commercial pig farms, groups of pigs are mass medicated through their drinking water with selected antimicrobials for short periods to manage herd health,” the paper’s abstract reveals.
“However, delivery of medication in drinking water cannot be assumed to deliver an equal dose to all animals in a group.
“The substantial ‘between animal’ variability is systemic exposure to anti microbial (i.e the antimicrobial concentration in plasma) resulting in underdosing or overdosing of many pigs.
“Three sources of the between animal variability during a water medication dosing event are differences in:
1. concentration in the active constituent of the anti-microbial product in water available to pigs at drinking 
appliances in each pen over time.
2. medicated water consumption patterns of pigs in each pen over time and
3. pharmacokinetics (i.e oral bioavailability, volume of distribution and clearance between pigs and within pigs over time).
“It is essential that factors operating on each farm that influence the range of systemic exposures of pigs to an anti-microbial are factored into antimicrobial administration regimens to reduce under dosing and over-dosing,” the abstract states.
More recently, Helen Crabb, University of Melbourne and Louise Edwards from Ridley, were the principal authors of a CSIRO supported research project, Animal Production Science 61 97) 637-644 https://doi.org/10.1071/AN20484 published February 18, 2021.
Context: Water is the first nutrient and an essential component of all agricultural production systems. Despite its importance there has been limited research on water, and in particular, the impact of its availability, management and quality on production systems.
Aims: This research sought to describe the management and quality of water used within the Australian pig industry. Specifically, the water sources utilised, how water was managed and to evaluate water quality at both the source and the point of delivery to the pig.
Methods: Fifty-seven commercial piggeries across Australia participated in this study by completing a written survey on water management.
In addition, survey participants undertook physical farm parameter measurements including collecting water samples. Each water sample was tested for standard quality parameters including pH, hardness, heavy metals and microbiological status.
Key results: Responses were received from 57 farms, estimated to represent at least 22% of ‘large’ pig herds. Bore water was the most 
common water source being utilised within the farms surveyed.
Management practices and infrastructure delivering water from the source to the point of consumption were found to differ across the farms surveyed.
Furthermore, water was regularly used as a delivery mechanism for soluble additives such as antibiotics. The quality of water at the source and point of consumption was found to be highly variable with many parameters, particularly pH, hardness, salinity, iron, manganese and microbiological levels, exceeding the acceptable standard.
Conclusions: In general, water quality did not appear to be routinely monitored or managed. As a result, farm managers had poor visibility of the potential negative impacts that inferior water quality or management may be having on pig production and in turn the economics of their business. Indeed, inferior water quality may impact the delivery of antibiotics and in turn undermine the industry’s antimicrobial stewardship efforts.
Implications: The study findings suggest that water quality represents a significant challenge to the Australian pig industry.
Access to drinking water of an acceptable quality is essential for optimal pig performance, health and welfare but also to ensure farm to fork supply chain integrity, traceability and food safety.
There has been much research committed to the study, not only of water quality but its use in the effective delivery of both vaccines and targeted medication.
Much of this research into drinking water quality and its further uses has been supported by the CSIRO, APL and APRIL.