Clear decisions on disinfectants can pay off
Most farmers are only too well aware of the value of cleaning and disinfection. Much advice is given on the importance of the thoroughness of this task. But often the missing link is the actual choice of product. There is little point in spending time and energy in meticulous cleaning and disinfection if the wrong, or unsuitable, product is being used in the first place. This is especially true if a particular disease is being targeted.
Jim Bigmore, director of specialist hygiene company, Hysolv, looks at the options for poultry farmers.
“We don’t have enough money to buy a cheap product,” my father always told me. What he meant by that was spending a little more and buying a quality product will usually save you money in the long run. This is echoed by the saying: “The most expensive product, is one that doesn’t work well.”
In the broiler business, buying a disinfectant purely because of a low price per litre may not bring the savings that are being sought. So, the first piece of advice is don’t let the company’s accounts department choose the farm’s disinfectants!
So, what decisions should guide the choice of disinfectant?
- Which diseases need to be controlled?
Bacterial: look at glutaraldehydes and chlorocresol-based disinfectants.
Viral: glutaraldehydes, peroxygen, organic acid disinfectants.
Coccidiosis: chlorocresol disinfectants.
Bacterial spores: chlorocresol, iodophors, peracetic acid.
- Which diseases may be monitored by the authorities?
- Which concentration of disinfectant should be used in calculating costs?
Certain disinfectant companies still publish misleading information on dilution rates that are ineffective in real-farming conditions. Therefore, always refer to the Defra or European Norm (EN) tested dilutions for reference.
Defra conducts tests at 4°C for 30 minutes (search for “Defra-approved disinfectants”)
Pros – testing criteria favours: peroxygen, peracetic and organic acid disinfectants.
Cons – testing criteria disadvantages: glutaraldehydes, chlorocresols, iodophors.
European Norm (EN): (search for “IHO-desinfektionsmittelliste”, the website is in English!).
EN14675 activity against all viruses
EN1656/14349 against all bacteria
EN1657/16438 against fungi and yeasts
EN tests may be performed using combinations of temperatures (4/10/20°C), contact times (30/60 minutes), organic loading (high/low).
Pros – testing criteria allows user to see in which conditions disinfectants are effective.
Cons – none that are obvious!
Of the two sources of information the IHO list mimics the conditions found on farms more closely. Comparing the Defra and IHO results will give the user an excellent overview of the disinfectants and allow them to break-through the ‘marketing-wall’ that surrounds some of the products.
- What time of year will the product be used?
Some product types are unaffected by changes in temperature, others act more slowly in cold conditions. (Anti-freeze can be added to glutaraldehydes).
Temperature independent: peroxygen, peracetic, organic acids.
Effective down to 4°C then slow-down: chlorocresol, glutaraldehyde, iodophor.
- Will the disinfectant be used in boot-dips?
Some disinfectant groups are neutralised by organic matter and this, of course, often quickly finds its way into boot-dips. A quick look at the IHO list mentioned in Question 3, will show which products are susceptible to organic matter. In general, this means that some boot-dip solutions will have to be refreshed more often if the disinfectant is neutralised. The following gives a rough guide to boot-dip solution refreshment:
Product type Refreshment rate
– Peracetic acid daily
– Peroxygen 1 – 2 days
– Glutaraldehyde/Iodophor/organic acid 3 – 4 days
– Chlorocresol weekly
- Will the disinfectant be used on vehicles, or sensitive equipment?
Some disinfectants can be corrosive to certain materials such as non-ferrous metals and unprotected iron.
Potentially corrosive at ready-to-use dilutions: peroxygen, peracetic, organic acids.
Non-corrosive at ready-to-use dilutions: chlorocresol, glutaraldehydes, iodophors.
Of course, the price per litre is important, but only after considering the previous 6 points.
When this list of questions is considered, which of these could be answered by an accountant? Probably only the last question – No. 7!
Don’t let your accountant choose your disinfectant!
The farm manager or the veterinary surgeon, on the other hand, should be able to answer all seven questions. The disinfectants companies can be used as sources of information, but usually they will favour their own products. Therefore, it is good advice to use the Defra and IHO websites to double-check the information you receive and then make sure you can answer the seven questions, before making your choice. In my experience in the field, the time spent can repay the effort many times!
In a broiler farm, performance and flock health are closely connected. Flock health and the choice of the correct disinfectant are also connected. So, instead of letting your accountant go through the books to find the cheapest disinfectant, ask the farm manager to go through the daily weight gain, feed conversion rate figures, to see, for instance, if a coccidial oocyst disinfectant has been good value for money. Or look whether the losses caused by disease have fallen when a different disinfectant has been chosen. That is the true bottom-line. This is the real criteria when choosing a disinfectant!