Consumption of water by animals exceeds that of feed, yet it is only feedmill biosecurity that is scrutinised through various quality assurance schemes, writes Murray Hyden
Farm drinking water quality is not well regulated and, unlike town water supplies which flow direct from the mains, farm supplies are often interrupted by header tanks to reduce pressure to drinker lines and troughs, or may even be collected from other sources and stored on farm.
For poultry, the key pollutants are sediments and faecal bacteria which significantly reduce the quality of water that is used for drinking.
An effective means of cleaning tanks, water pipes and complete drinking systems is essential in order to optimise bird performance. This is because biofilms can often be seen on the inside of water pipes as a slime layer and can become a self-perpetuating source of pathogenic infection.
Biofilms can lead to leaky drinker nipples inside the house, which in turn causes wet litter and increased ammonia production. This results in reduced performance and liveability.
There are a number of other issues affecting poor water quality. Water contaminated with micro-organisms, algae, dust and rust is also common on farms and in serious cases this can have a greater negative impact than poor feed quality.
And, despite the common perception that water quality in the UK is of a high standard, this is not always the case. For example, it is estimated that more than 40% of privately-owned supplies are contaminated with the coliform bacteria, which can enter the water from a variety of sources, including sewerage, animal waste or dead animals.
Iron bacteria are also a major nuisance in many well-water supplies and form a reddish-brown slime that coats the inside of pipes, fouls pumps and clogs drinkers.
Cyanobacteria, or blue green algae, can produce toxins in drinking water while other algae can produce compounds which cause offensive flavours in poultrymeat or simply result in the birds refusing to drink.
The key challenge for all producers is that the bacteria and algae that produce biofilms can be very difficult to kill. Common disinfectants and sanitisers cannot penetrate or degrade the cell wall or the layers of slime that provide contaminants with additional protection from disinfection.
Simply flushing with water is not enough and it is necessary to add some form of organic acid to water lines prior to flushing. In general, acid treatments are the best option to break the biofilm and dissolve sediments, while chlorine is best to prevent these problems from returning.
When using acids it is important to note that all acidifiers are not the same. Citric acid for example is an organic acid commonly used by poultry producers for acidifying their water, yet citric acid does not have good antimicrobial activity.
A solution is to effectively “shock” water lines, by using a partially buffered acid product, such as Salgard liquid to acidify the lines and break down the biofilms.
This should be applied between flocks for a long enough time so the shock will destroy the biofilm, dissolve the mineral deposits that have accumulated and kill potential vegetative bacteria and algae.
Once the biofilm has been loosened from the system it is necessary to flush out the acids and the released biofilm with fresh water to remove the biofilm deposits that can block lines or drinkers.
After this it is necessary to use a product to ensure safe drinking water and provide on-going protection by preventing biofilm build-up in tanks, lines and drinkers.
The active ingredient sodium troclosene (NaDCC), or a tablet of self-dissolving Aquasafe, can then be used to effectively treat drinking water. For the more difficult to access header tanks, an NaDCC concentrate can be prepared and administered by using a Dosatron-type dosing system.
For troughs and cisterns, the Flogenic system, using trichloroisocyanuric acid (TCCA), where a single applicator is fitted directly to the ball valve, will accurately dose up to 90,000 litres a unit.
* Murray Hyden is director of biosecurity, Anpario, the holding company for feed and water additive companies, Optivite and Kiotechagil.
Tips for an effective cleaning system:
- Flush the drinking lines with water, using a high-pressure flush to remove loose sediment
- Use a strong buffered acid product at recommended strength. Wear necessary protective clothing
- Ensure that there is sufficient acid volume to flush the lines completely
- Flush the water lines, dosing pumps, valves and tanks with the selected product and use a broom to open the nipple drinkers
- Allow lines to soak for a minimum 60min; overnight is better
- Flush with clean water to remove loosened biofilm, debris and remaining acids.
- When all acid residues have gone, charge the drinking lines with fresh water treated with a chlorine-based disinfectant
- Check the last drinker in the line for chlorine using simple test strips. If none is found, increase the inclusion rate