Drinking Water Sanitation – Pigs & Poultry
The importance of good drinking water is often underestimated. For instance pigs drink more than twice as much as they eat! At weaning the water/feed ratio is about 4:1.
Water transports the nutrients in the body and thus determines the digestion process, regulates the body temperature and eliminates toxic wastes keeping up the health status of the animal. Water therefore has a significant impact on both the health and the production of animals.
Water itself can be a source of contamination when its microbiological condition is not optimal i.e. the water carries too many germs. Also its chemical composition e.g. hardness, level of iron, level of calcium or acidity, can impede sufficient consumption Digestion and absorption of additives like medicines, vaccines and vitamins may also be reduced. Waters' physical aspects such as taste, odour etc. can also affect the rate of consumption.
Creation of biofilm
The addition of additives such as medicines, vaccines and vitamins act to create an extracellular polysaccharide layer inside the pipes, known as the biofilm. Simple sugars such as dextrose for instance will encourage biofilm production. Microorganisms then attach themselves to this layer inside the pipe. The biofilm is between five and 500 micrometers thick. Inside it, various microorganisms will develop and ultimately contaminate water passing through the tube/pipe and hence act as a source of contamination of drinking water. This biofilm is not usually visible inside your drinker lines, but it will often be present.
Mineral deposits, especially calcium, will also tend to build up to form lime or scale inside the drinker lines and provide a shelter for microoganisms.
The biofilm contains a very heterogeneous population of organisms. At its outside, where more nutrients are to be found, there will be aerobic bacteria, such as Pseudomonas spp.. In between, we find micro-aerophile bacteria such as Legionella spp. and Campylobacter spp., aerotolerant anaerobe bacteria and nitrate reducers such as E. coli. In the deepest levels (closest to the pipe), we find anaerobe bacteria such as sulphate reducers (desulfovibrio).
The adhered microorganisms will develop, by evolution and mutation, different characteristics, compared with their free-floating co-species. Immediately after adhesion they will develop a stem which allows them to create a matrix structure. They then become immobilised biofilm bacteria. They will now be able to increase their resistance and because of their changed cell structure they become more hydrophobic (water-hating) because of changed outer membrane proteins and their development of stress proteins thus increasing their resistance against a number of factors. Their tolerance levels of classical biocides, such as chlorine will be considerably higher. Thus they will become more difficult to eradicate.
In metal pipes biofilms can cause microbiological induced corrosion. The anaerobe sulphate reducing bacteria produce sulphides which will adversely affect the odour and/or taste of the water. The water can become red through the corrosion of iron pipes.
Pipes must therefore be cleaned to remove biofilms and lime scale. Chlorine will not remove the biofilm since it will not penetrate the biofilm and its effect will be less at the end of the pipeline, as chlorine gets neutralised by organic matter or the scale. The use of chloride will also add a taste and smell to the water pipes.
A stabilised combination of hydrogen peroxide and organic acids will destroy the biofilm and/or scale. It is advisable to flush your main supply pipes once this biofilm layer has been dissolved, in order to remove it physically. Only then can you start to clean your lines. It is also advantageous to further treat your water during the production cycle. Further water treatment should avoid a new build-up of biofilm and scale allowing your drinking system to function optimally. It will also sanitise your water.
It should be remembered that the waterflow in the pipe is extremely low at the end of the line. Here the water will be warmest, and the biofilm deposits will have built up the most. Hence the contamination and infection risk will be highest.
Optimum production results will be reached when the level of pathogens in the water is low, and when digestion is optimised by the addition of probiotics, a balanced ration and good management combined with other good biosecurity measures.
Organic acids in the water will act to acidify the gut which acts to encourage the population of Lactic Acid Bacteria which have an optimum pH of 2-4 (E. coli is suited to a pH of 4.5-8). The addition of a probiotic at this time will act in synergy with the organic acid acidifier.
It is important when choosing a water sanitiser to ensure that it does nothing to damage the animal, the user, the consumer or the environment.
It is important to always supply clean water in order to encourage consumption and reduce the pathogen load of water. This will in turn encourage production by improving digestion and reducing disease and mortality levels. |
