How acidification of water improves gut health

19-09-2017 | | |
How acidification of water improves gut health. Photo: Tim Scrivener
How acidification of water improves gut health. Photo: Tim Scrivener

Acidifying water is a key part of eliminating pathogenic bacteria, promoting healthy gut flora and ultimately boosting bird health. However, it’s vital to get the right balance, as Olivia Cooper reports.

Clean water is an essential part of bird health – but it’s not as easy to get right as one might imagine. There are many levels of water cleanliness and hygiene: Most people think of cloudiness and contaminants when it comes to dirty water, but even the clearest looking mains water can carry hidden dangers.

Water quality: Foundation of animal health

According to Richard Turner at Applied Bacterial Control (ABC), part of St David’s Poultry Vets, water quality is the foundation of good nutrition and animal health. “Birds consume nearly twice as much water as feed under normal climatic conditions,” he explains. “Water plays a vital role in digestion, transportation of nutrients, body temperature regulation and removal of waste products from the body. It has a huge impact on bird health and farm performance.”

There are two key aspects to clean and healthy water on-farm:

  1. terminal hygiene at turnaround
  2. ongoing water treatments like organic acids.


Farmers will already be flushing through their water systems at the end of every flock, but it’s the small details that can make a big difference to the effectiveness of this routine, says Mr Turner. “It sounds simple, but read the instructions on the cleaning product and follow them. Lots of people think leaving it in the lines for longer will produce a better result, but that isn’t always the case. It will break down the biofilm initially but if left too long it can resettle and become difficult to flush out.”

What is biofilm and how to remove it?

“It’s a community of bacteria, fungi and algae bound together in a slime which anchors them firmly to a surface and protects them from antibacterial agents, so they can proliferate,” he explains.

Peracetic acid-based cleaners are particularly effective in removing limescale-based biofilms, while hydrogen peroxide is good against biofilm and organic matter. “Whatever you use, follow the recommendations on the label.”

However, if there is a heavy bacterial load, a 1% concentration is unlikely to work well, so Mr Turner recommends going up to 2-3%. “Consider what was done in the crop before: If you tested the water and had no health problems 1% should be fine. If you put lots of additives and medicines through the line there will be more residue, so up the rate a bit.”

Testing the water

Water quality will affect how much the birds drink, and in particular pH can influence the taste and potential bacterial burden. “Pathogenic bacteria prefer alkaline environments while ‘good’ bacteria prefer acid conditions,” he explains. Water with a high pH can also affect the efficacy of antibiotics and vaccines, while very acidic water can be unpalatable and will corrode equipment.

Optimum pH level

The optimum pH is between 5 and 6. Harder water will require more treatment to reach that target than softer water. “If you have a borehole, get it analysed every 6 to 12 months, to understand what minerals are in there, as different combinations can produce an adverse reaction in poultry.” For example, high sodium and chloride levels can cause wet litter issues, as can magnesium and sulphate or sulphate and sodium. “Even if you have mains water it’s worth getting it tested for hardness and pH, and use dip sticks or handheld meters more regularly to check water pH in the drinking lines.”

Water softening equipment

Typically, water softening equipment uses ion exchange to remove the calcium and magnesium ions and replace them with sodium ions. However, this can increase sodium levels to unacceptable levels, so producers should be judicial in their selection and use of water softening equipment, warns Mr Turner.

Continual sanitation

To prevent the build-up of biofilm throughout the flock, water treatment options include ultraviolet filters, electrolysed water, chlorine dioxide, and chlorine tablets. Hydrogen peroxide can also be used while birds are in-situ, at a much lower rate than during turnaround – and is a useful option after including additives like vitamins, minerals or medicines to undo any damage to the line condition.

Organic acids

As well as the above options, producers should consider including organic acids, which act as a feed source for beneficial gut microflora, according to Mr Turner. “You don’t want any bacteria in water increasing the chances of birds picking up a health challenge.”

Organic acids have a triple benefit:

  1. they help sanitise the water
  2. break down limescale
  3. promote gut health

Reducing pH with organic acids

Organic acids reduce the pH of water – when used in conjunction with another sanitiser like chlorine the optimum pH is 5.5. However, if using acids alone producers should take the pH down to between 3.8 and 4.2, to eliminate pathogenic bacteria from the water. “Birds do prefer acidic water and are quite tolerant to it, but if you get close to a pH of 3.5 it will damage the gut lining,” he warns.

Using buffered or protected acids

It is important to use buffered or protected acids to ensure they reach the gut in their complete form. “Acids work in the gut by passing through the bacteria cell wall, where they dissociate and lower the pH inside the bacteria,” explains Mr Turner. “The cell then has to utilise its energy to restore its pH, disrupting the bacteria’s metabolism and preventing the pathogenic bacteria surviving. If the acids are un-protected they will dissociate before they reach the gut and be unable to have a positive effect.”

There are a wide range of organic acids available: Formic acid and propionic acid are particularly effective at controlling E.coli and Salmonella, whereas lactic acid and butyric acid are important in promoting beneficial lactobacilli in the gut microflora.

Automated dosing system to ensure safety

Acids, chlorine and other sanitation products can be dangerous unless handled extremely carefully, so Mr Turner suggests investing in an automated dosing system which alleviates the need for manual handling and measuring. “You can also then be confident that you’re consistently using the correct levels throughout the flock.”

For optimum bird health he recommends including probiotics either in the water or feed, to boost gut integrity and immune function. But Mr Turner warns continual sanitisers will kill most probiotics, so it’s important to switch off when adding products. However Biacton, which St David’s distributes in the UK, is quite tolerant to chlorine, he says.

Case study: Water focus pays dividends for flock performance

Charlie Simpson rears 542,000 broilers each crop at Lower Heath Farm, Whitchurch, Shropshire, and introduced a comprehensive water treatment regime about 3 years ago.

Challenges of borehole water

“We use borehole water which I know isn’t the best in the world,” he says. “We have it tested every 6 months, and have an ultraviolet steriliser in every shed.” The water is high in manganese, iron and sulphate, so Mr Simpson uses a reverse osmosis unit to remove trace elements; the waste water is used for washing down yards. “Hygiene is very important, but water hygiene is often overlooked.”

Charlie Simpson rears 542,000 broilers each crop at Lower Heath Farm, Whitchurch, Shropshire. Photo: Charlie Simpson

Charlie Simpson rears 542,000 broilers each crop at Lower Heath Farm, Whitchurch, Shropshire. Photo: Charlie Simpson

Turnaround – flushing all the lines

At turnaround, Mr Simpson flushes all the lines – including underground pipes – out with a hydrogen peroxide-based product, leaving it for 12 hours before flushing that out with fresh water, which is done again just before the birds come into the sheds.

After stocking – adds chlorine and organic acids to water

Once stocked, he adds chlorine and organic acids to the water using an LMS automated dosing system, lowering the pH from 7.4 to around 5.2. “Clean water is probably the most important ingredient you give to your chickens, especially if you take into account how much of their body mass is made up of water,” explains Mr Simpson. “That’s why I’m happy to spend money on getting it right.”

Water cost is £0.02 per bird

Mr Simpson reckons he spends about 2p/bird on his water. “It easily pays for itself through the benefits to gut health,” he says. “We now never have to top up bedding and we have very good pododermatitis scores. In addition, the water lines and drinkers are really clean; before we always had a slimy layer – now we don’t get any biofilm build-up.”

Probiotics and essential oils in feed

As well as treating the water, Mr Simpson adds probiotics and essential oils to feed to boost the birds’ gut health and immunity at around 3 weeks of age. “At this time the birds are undergoing a feed change, being vaccinated against Gumboro disease and also going through their optimum growth phase,” says his vet Suzie Ackerley from St David’s Poultry Team. “This combination means intestinal health can suffer; the essential oils help to support the birds by stabilising the intestine and reducing leakage of bacteria into the bloodstream.”

A fimbriae blocker – to reduce E. coli attachment

Mr Simpson is also experimenting with Zoolac – a fimbriae blocker – at day-old to try and reduce E.coli attachment. “The stronger and healthier they are the better. We can’t use any starter medication any longer so we’re trying to give the birds the cleanest and best quality water so as not to introduce any harmful bacteria along the way.”

Slashed antibiotic usage by 70-80%

Having implemented the changes, Mr Simpson has slashed his antibiotic usage by 70%-80% in just 3 years, and qualified for Aviagen’s coveted ‘400 Club’ – which recognises the highest performing broiler producers in the country – 3 times in a row. “It’s really a combination of everything pulling together,” says Mr Simpson. “It’s all about prevention rather than cure.”

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