Natalia Furman, DVM, MRCVS, a poultry veterinary surgeon with Poultry Health Services, looks at the importance of clean water for poultry.

AS UP to 70 per cent of the chicken’s body consists of water, this element is a crucial factor for bird performance in poultry production.

Water is a vital nutrient in poultry metabolism, playing an important role in digestion, absorption of food, transportation of nutrients in the body and elimination of waste products via urine.

However, water with a high bacteria load can cause disease outbreak in the poultry shed and can provoke the creation of biofilm in the drinking system, which can pose a threat to human health and the finances of the farmer. Therefore, systematic control of the water quality is a must and will improve the bird’s performance together with its welfare and enhance financial profit for poultry producers.

Water microbiology

The table presents important bacteria with the reference values, which potentially can cause disease outbreak in poultry shed.

Total bacteria level indicates the overall level of bacterial contamination. It tells us how much bacteria there is in our water system, however, not confirm their pathogenicity.

Good practise is to keep the levels below 500 CFU/ml, but the lower, the better. High numbers do not necessarily mean the micro-organism in a water is harmful, but it does mean that, potentially, there could have been a pathogenic germ present in the water.

The total bacteria level is a good indicator of the cleaning efficiency of the water system in the poultry shed. Moreover, a high bacteria levels can impact the taste of water resulting in reduced consumption by birds. If you have a high TVC’s number, it is good practice to ask your vet about the water hygiene results and discuss with them.

Coliforms and E Coli are microbes that are part of the physiological flora of digestive tract of all animals including poultry. They can also come from the spreading of muck on land which then drains through to boreholes.

If found in the water at any level, they can pose a significant threat to the bird’s health. It is one of the opportunistic pathogens responsible for several disease conditions such as yolk sac infection, air sac disease, perihepatitis, enteritis, omphalitis and coligranuloma.

The presence of any faecal coliform indicates that water is unfit for consumption by poultry. It is advised to check the water hygiene at least once per flock and always after the cleaning and disinfection process, if the farm was having the water-related issue before, the check should be done even more frequently. Test water hygiene by sending the samples to the veterinary clinic.

Pseudomonas is a very important microbiological indicator of the presence of biofilm in the shed, and has an impact on the flock performance as well.

When S aureus is found in tested water, hygiene of a drinking system needs to be improved. It can cause a leg problem in broilers as well as performance reduction and disease issues. Typically, it can be found on the skin of the birds, but it should not be present in water. It can take part in biofilm’s creation.

What is biofilm?

Biofilm is a microscopic layer of bacteria for example Pseudomonas and other substances that lines water pipes. It provides other, often more harmful bacteria like Salmonella, E Coli or S aureus, with an environment to grow and evade sanitiser, allowing them to survive.

These micro-organisms can be shed periodically from the biofilm, so are not always found in samples, even when present, for Salmonella sampling, it creates severe issues for the poultry producers. When Salmonella is positive, this can cause a massive financial loss for the business and can be a human health threat as well.

It is not easy to remove biofilm, therefore, it is better to prevent its formation. Performing the microbiological analysis of drinking water and determining the biofilm capacity is very important for public health. E Coli strains and Campylobacter or Salmonella are a concern for human health. Moreover, the intake of poor-quality water can be the cause of the disease because all animals have access to the same drinking water.

What can be done if the water hygiene is poor?

It is recommended to take the water samples at least once per flock; however, it can be done more frequently. It is important to be sure that the water for the animals is always excellent. It is a good practice to take the water samples from the borehole, at the start and at the end of the water line in a shed. We can localize the issue and act faster to solve the problem on the farm then implement sanitation programs such as gas chlorine, bleach, chlorine dioxide, hydrogen peroxide or other sanitizers. If you are sanitizing your water system with your birds in the shed, make sure that you have flushed your lines before. Use your disinfectant at a low dosage and make sure that is not going to do any harm for the birds. If you are doing clean and disinfection at turnaround, make sure that you have used the correct disinfectant. Effectively cleaning the water system (including drinking lines) helps to remove biofilm and scale build-up as it can act as a food source and hiding place for harmful pathogens. It is advisable to ask the sanitizer producer or your vet to assist you with solving the problem. It is important to keep medicator buckets clean and covered.

How to take an adequate water sample?

It is important to take the samples in a very clean way – use gloves and disinfectant in wipes. Steps to take the perfect water sample: put the gloves on; prepare your disinfectant wipe; clean all surfaces near the place where you want to collect the sample; flush the very first stream; do not touch the sample container with anything; take the water sample; and write all information on the submission form.

When is the risk bigger than usual?

The major risk is for one-day old chicks. The temperature in the shed during the first week of the production cycle is relatively high, above 30°C normally. Due to the small intake of the water of one-day old chicks, water flow through the lines is lower than at other times of poultry production.

That makes a perfect scenario for bacteria growth and biofilm can be created in the future, which is later not easy to remove. This is a critical moment for taking care of water quality. Small birds are also more vulnerable to harmful bacteria, which might be the reason for bad performance of the flock in the future.


Water quality is crucial. It should be so good that we, as humans, would not have a problem to drink the water from our poultry shed. Testing of water is relatively cheap by comparison to medication costs of disease outbreak and other possible consequences. This is the best and the simplest preventive method to control the water hygiene on the farm. Find your local poultry clinic and ask the vets about possible solutions about how to have the ideal water for the animals, before having an issue on the farm.