Drinking water medication: beware of interference

Medication should never replace good management, but sometimes a treatment is unavoidable. In poultry and pigs, medication is often administered via the drinking water. The water quality largely determines how successful the administration will be. The water composition influences the solubility and biological availability of the medication and can even have an influence on the efficacy. Hardness, pH, iron and cadmium levels are some important parameters that can interfere with the medication. This counts for medicines in general, but is of particular importance for antibiotics because partial inactivation of the antibiotic can cause antibiotic resistance. The following should be kept in mind when using antibiotic water medication:

Ampicillin/amoxicillin need a neutral to basic pH to dissolve well. They are sensitive to temperature swings and to the enzyme ‘beta lactamase’ that can be produced be bacteria present in the drinking water system (biofilm!).

Tetracycline’s are poorly soluble. Calcium in hard water forms complexes with tetracycline’s. These complexes are poorly absorbed in the digestive tract. Acidification of the water can improve the solubility as well as the absorption.

Sulphonamides can be captured by organic substances.

Most antibiotics are unstable in solution (e.g. amoxicillin solution: shelf life 6h). They should be administered in an appropriate volume of water so that the animals drink everything in time.

These examples illustrate the importance of water quality when administering antibiotics. For each specific antibiotic treatment via the water, the compatibility of the antibiotic with the drinking water (and water treatment products!) should be discussed with the advising veterinarian.

Methods to reduce iron and manganese levels at the drinking water source

Besides hardness, iron is also an important cause of problems in the drinking water system. The danger doesn’t lie within the iron itself but in the unpleasant side-effects of its presence. Iron excess gives rise to discoloration of the water, scaling, pipe or nipple blockings, metal taste, promotion of biofilm etc. This affects animal health and can therefore indirectly increase antibiotic use. Manganese excess often comes along with iron excess and causes similar problems. Luckily there are several techniques to remove iron and manganese at the drinking water source:

De-ironing: This is an automatic technique that consists of two steps. 1) By aerating, the soluble iron (Fe2+) precipitates and becomes insoluble (Fe3+). These iron particles are then filtered out with a (sand) filter. Different variants of this technique are available, e.g., with an underground installation. The functioning of the system should be monitored regularly.

Ion exchange: a cation exchanger removes iron and manganese as well as calcium and magnesium from the water by exchanging them for sodium. This happens in column with a resin medium. Removing calcium and magnesium softens the water. This is an automatic technique but periodically, the resin medium needs to be regenerated.

Sedimentation basin: only works for moderate iron/manganese excess. The water flows slowly through an open basin. By periodically aerating the basin, iron and manganese precipitate and sink to the bottom, just as other suspended particles. This results in clear water.

Zeolite filter: zeolite is a rock that can be used as ion exchanger (same principle as above) or as filter. In the latter case, three steps are performed (filtration, regeneration, washing) to remove iron and manganese.

Prevention of (blue-green) algae in drinking water sources

Algae and blue-green algae (Cyanobacteria) typically cause problems in summertime: they thrive in stagnant or slow flowing warm water with high levels of nutrients that is exposed to sunlight. Algae can make the water pH rise or cause blockages in the piping. But especially blue-green algae are a threat to animal health. When the layer of blooming algae starts to decompose, toxic substances are released. These toxins can cause a wide range of health problems, from mild to lethal. Consequently blue-green algae can indirectly promote unnecessary use of antibiotics.

Once algae have started to bloom, there is no way back. Prevention is the key to cope with algae. When drinking water supplies are stored in a basin, different techniques can be used to prevent algae growth.

Light shielding: this is the most efficient method as algae cannot survive without light. The water surface can be protected from light with a (floating) sail or if this is not possible, floating balls/hexagons. A regular check-up of the shielding is strongly recommended.

Aerating/stirring the water: This inhibits algae growth by increasing the oxygen levels in the water (aerating) and creating water flow (stirring).

Ultrasonic sound waves higher than 20kHz are an effective method to kill present algae and prevent their growth.

Certain water plants prevent algae growth by production of substances that prevent or slow down algae growth. Other plants compete with the algae for nutrients in the water, thus inhibiting algae growth.

Why and how to prevent biofilm formation in drinking water pipes

A biofilm is a slimy layer sticking to the inside wall of the drinking water pipe that is created by the growth of microorganisms on mineral deposits or organic material. When the biofilm loosens or bacteria are released from it, problems such as reduced production, disease, decomposition / scavenging of water additives and a reduction in the effectiveness of medication can arise. Due to the presence of biofilm in the pipes, the bacterial pressure can rise incredibly between the water source and the drinking point! Moreover, biofilms can promote the development of antibiotic resistance. It’s important to focus on prevention of biofilm. Indeed, besides a poor bacteriological quality of the drinking water, biofilm can cause other problems such as blockage but also corrosion of the pipes. Furthermore, thick and tenacious biofilms will require high doses of strong biocides. This increases the risk of health problems due to biocide residues in the water. One hundred percent prevention is often not possible, but several measures can significantly slow down biofilm formation.

The piping material: polyethylene pipes are prone to biofilm formation whereas copper piping is less sensitive.

Bacteria love stagnant (warm) water: avoid dead ends in the piping and assure a good flow at all times.

Iron and manganese in the water promote biofilm formation. Check the DISARM best practice guide for water quality for methods to remove iron and manganese.

Regularly clean the pipes (see also DISARM best practice guide for water quality)

Some water treatments / additives (e.g., butyrate, acetic acid) can contribute significantly to the formation of biofilm or slime formation, depending on the water source.

Effective water vaccination: the importance of water quality

Good vaccination schemes are an important part of good farm management. Vaccination prevents diseases (and secondary bacterial infections) and thus antibiotic use. Many live vaccines can be administered via the drinking water, whereas some need to be injected. Drinking water vaccination is very practical, but the efficacy is highly influenced by the water quality/composition. These important points concerning the drinking water should be kept in mind at all times:

Use water of high quality! Unwanted components can interfere with the vaccine. Unpalatable water can be detrimental because of lower water uptake. Check the DISARM Best Practice Guide for water quality for more information on how to evaluate and remediate water quality.

At least 48h before vaccination: cease all water treatments. In case of live bacterial vaccines (e.g., Salmonella, Mycoplasma): stop antibiotic treatments at least 7 days before AND after vaccination.

Flush the pipes thoroughly to remove all residues of cleaning and disinfection products. This is essential to avoid inactivation of the vaccine.

Add a water stabilizer that binds substances such as chlorine in tap water to avoid vaccine inactivation.

Check the DISARM best practice guide for vaccination protocols for more information on effective vaccination practices.

Source: N. Sleeckx, Drinkwatermedicatie, Proefbedrijf pluimveehouderij vzw, 2014.

Bring out slurry and manure – but avoid spreading of pathogens

Slurry and manure can contain pathogens. To avoid spreading of infectious diseases between farms or spreading of pathogens around your farm it is important to take precautions.
First, get an overview of the overall logistic – where are the traffic routes on the farm. Pay special attention to routes for transport of slurry and manure. Avoid using the same routes for the feeding trucks, both inside and outside. Always keep a good safety distance to the feed.

Sometimes the slurry tank or lagoon is placed in a way that the slurry tanker must cross the same route the feeding truck uses. In these cases, have a plan for cleaning up these crossings and make sure it is done. This is a way to minimize the risk of spreading pathogens.

When handling slurry and manure keep distance to the stables and animals to prevent exposing animals to pathogens.

The most optimal route for safe transport of slurry and manure might be a little longer, but it is worth it compared to the consequences of spreading diseases in your herd.

Avoid spill when filling the tanker and under transport of slurry and manure. When spillage occur, there is a risk that pathogens can be spread around the herd via footwear and vehicle tires contaminated with slurry or manure. Therefore, be careful when handling slurry and manure and implement good routines for fast cleaning when spillage accidentally occurs.

Slurry contaminated vehicles and equipment can also spread diseases between farms. Make sure that only clean and disinfected equipment enter your farm. If the vehicle and equipment is washed and disinfected on your premises, then do it in a place where washing water do not get close to stables, animals or feed. Spreading pathogens with aerosols during washing with high pressure is a serious hazard. Make sure that aerosols do not enter stables or feed.

HACCP based biosecurity plan for a laying hen farm

The biosecurity plan is an important part of health control measures to protect the flocks and individual hens against pathogens.
The biosecurity plan based on the HACCP (Hazard Analysis and Critical Control Point) principles offers the best assurance that commercial egg industry flocks are protected against serious disease outbreaks.
That is also the best way to ensure the food safety of the egg production.
The basic procedures of the biosecurity plan include both aspects related to laying hens’ welfare conditions, bird health and aspects related to the food safety.
Another major issue is the the prevention of emergency diseases, as follow : Newcastle Disease virus (the highly virulent strains), avian Influenza, infectious bursal disease, and Salmonella spp. infections (Salmonella enteritidis).

The critical monitoring points identified are:

1. Entry of chicks (at 15-16 weeks of age), equipment, vehicles, people and feed into pullet farms
2. Entry of adult fowls, equipment, vehicles, people and feed into egg production farms
3. The presence of wild bird and rodent faeces in sheds or where hens and pullets range
4. Water sanitation on farms using surface water
5. Disposal systems for dead birds, reject eggs, litter and manure from the farm
6. The presence of non-poultry bird species, other poultry and other animals on the farm

Biosecurity measures on poultry farms

Biosecurity is the major factor to have poultry health and a good poultry production and it is the most cost-effective means of disease control management .
Biosecurity is ensured on a poultry farm by implementing a set of organizational and technical measures in order to prevent the introduction, persistence and spread of pathogens, as well as in order to protect animal and public health.
The key objectives of a biosecurity plan for a poultry farm:

1. preventing the penetration of pathogens (exclusion of pathogens or external biosecurity)
2. reducing the penetration / spread of pathogens already existing among animals (biomanagement or internal biosecurity).
3. preventing the penetration / spread of pathogens existing in the farm to other non-infected farms / animals (e.g. biocontamination).
4. minimizing the incidence and spread of pathogens that impact the health of the population (zoonotic infections).

The biosecurity measures are as follows:

I. Defining biosecurity zone (the farm perimeter)
II. Functional sanitary filter for the employees, visitors, vehicles and all other entries
III. Visitor guidelines to be properly mentioned outside and inside the farm.
IV. Maintenance of the facilities used for housing, feeding and watering animals
V. Feed supply
VI. Transporting live animals to and from the farm
VII. Code of good practice and good hygiene practice (training of the employees)
VIII. Practice the technological principle “all full, all empty” at the hall level

Genomic selection

Genomic selection is a modern tool used in animal breeding, based on information from tens of thousands of markers associated with genes that influence animal production. The advantage of using the study of DNA or genetic markers is that it is possible to know if an animal has genes in its genome that influence the development of a certain characteristic important for the production or health of the animal. Thus, it is possible to obtain: a significant increase in the selection intensity and of the selection precision; significant decrease in the value of the intergenerational interval, doubling the genetic progress that can be achieved with each generation.

Genomic selection can help breeders identify individuals with higher breeding values as early as possible. Genomic selection or molecular marker-assisted selection also helps us to quickly eliminate pathogenic genes or those that negatively influence economically important traits from the population.

Selection assisted by molecular markers also has the advantage of facilitating the very rapid introduction of an important gene or group of genes into the genome of a population, a procedure called gene introgression in the population, achievable in a maximum of 2-3 generations. An example of the use of introgression may be the bringing of the gene responsible for resistance to certain diseases from a natural donor breed to a breed with very good production.

Step-by-step plan for chemical disinfection of drinking water pipes

Safe drinking water is essential for healthy animals. Contaminated water can quickly lead to health problems and thus increase the need for antibiotic treatments. Therefore, it is very important to pay attention to the drinking water and pipes. Reduction of the bacteriological load of the water is often achieved by a treatment with a disinfectant such as chlorine or peroxide (= chemical disinfection). When choosing the product and dosage, several factors must be taken into account: the contamination at the source, any additives, vaccines or medication that will be administered via the water, the presence of biofilm or lime scale … Therefore it is highly recommended to discuss with your vet or advisor which treatment is appropriate for your situation., An effective chemical disinfection of your drinking water system can be obtained with the following step-by-step plan (note, only perform in between production rounds!):

1. Open the pipes and drinking nipples.
2. Add the prescribed dilution (depending on the product) to the drinking water system by means of a dosing pump.
3. Measure the water at the end of the pipes with the test strip supplied to check whether there is sufficient product in the entire system.
4. Close the pipes and drinking nipples and let the product take effect. The contact time depends on the product used.
5. Open the pipe and nipple drinkers and flush abundantly with water.
6. Check if the drinking nipples are functioning properly before new animals are allowed into the stable.
7. Check again with a test strip at the end of the line whether all remaining product has been removed.