Richard Turner MA VetMB MRCVS
When developing a turnaround schedule, we must get back- to-basics. Our recommendations are based around the products and combinations we believe are best suited to various microbial loads in a shed, and the use of the correct product applied in the correct way is the foundation to good performance. The opportunity to clean the shed effectively at turnaround should not be missed and should be properly controlled. It should also be assessed with audits and TVC swabs.
As a start to all programmes, you need to be sure that the detergent you use on the equipment and building is of a heavy-duty nature, high foaming and cleans well. Disinfectants in general reduce the bacterial levels but do not make the surface sterile. Therefore, the better the preparation through the detergent used, the more effective the disinfectant.
The choice of disinfectant is sometimes based on non- scientific reasoning, such as price, ease of collection, ease of removal of empty drums and even, “I like the supplier”. Careful consideration is required for the system you use for the one big opportunity to set the new crop up well. Any disinfectant used by a farm should be Defra approved. Looking at the Defra trial work, the two standout products that are currently available are Interkokask and Intercid.
Intercid is comprised of Glutaraldehyde and Formaldehyde which are particularly effective against Salmonella when used at the correct rate. Many ‘anti- coccidiosis’ disinfectants are Defra approved against poultry bacterial and viral pathogens; however, many have no Defra (or equivalent) approval specifically for coccidiosis. Interkokask is one of the few approved anti- coccidiosis disinfectants. Always ensure any anticoccidial disinfectant has approval specifically for coccidiosis.
Litter beetles are an important reservoir of disease. No matter how well a shed is cleaned and disinfected, if litter beetles survive then they will carry many diseases for more than two weeks. For most farms a two-week turnaround is neither possible nor financially viable. Beetle traps are an excellent way of monitoring beetle numbers and there are many insecticidal products available such as CBM8.
Water lines need to be emptied and flushed using either Aqua-clean, if the pump system can be set to at least 3%, or Huwa-San if only 1% dosing is possible. The drinker line should be emptied onto the cleaned floor and then left empty until the day prior to fill. If there is a plan to keep water in the line, then after cleaning the shed the line needs to be disinfected again. Even if there is an in-crop water sanitising system in place we would also recommend the use of one of these products. We have tested them compared to others on the market and consider them to be superior. A fully automated Chlorine Dioxide system from FarmWater Ltd is the best on the market but comes at a high capital cost. The payback is very low chemical costs compared to Hydrogen Peroxide. The type of system you use needs careful consideration, and a site survey is the first step to defining a water hygiene plan.
Using a terminal application of formalin has been used successfully for decades and is cheap. Yet, as we all know it has major health issues and so we have moved to hot fogging with Halamid as an alternative option to our clients and it has proven very effective. This is a service we can provide and supply the chemicals for, as well as working with your cleaning company to offer this.
If a challenging microbial population of pathogens is left on the site, then all we are doing by not choosing well is increasing the risk to the farm’s future profit. Ultimately, there is always a balance between the time available, the cost of the programme and the financial return. After 38 years in practice, what is very clear is the better the cleanout, the better the subsequent performance. What is also clear is too many crops with shortcuts will take as long to recover as it took to get into the situation in the first place.
Over the last 2 years, for many good reasons, we have seen some clients struggling to get good production in even relatively new sheds. Maybe due to staff shortages, and no doubt associated with income levels, there has at the same time been a move to only dry clean sheds with the possible late addition of some disinfectants onto what is basically a very soiled surface. This has slowly led to poor performance, poor peaks, and some increased mortality with E.coli on many farms, which can be very difficult to get back under control once established. Dry cleaning of free-range sheds is a waste of time and should only be a last resort where there are issues of waste water control or severe shortages of time.
Often, following poor cleaning, the levels of red mite on many sites remains too high and subsequent flocks become infected early on as they are under stress coming into lay, leading to more E.coli leakage from the intestine and more mortality. The problem goes on and everyone is stressed.
The greater the investment in ensuring your new flock is housed in a clean, sterile, oocyst and worm free environment, the greater the chance the flock will go on to perform well. Performance of a laying flock is reliant on many factors; the stress of disease challenge is a key factor and could be the deciding factor.
An effective turnaround consists of the following steps:
- Dry clean down. Remove all organic matter from the shed such as litter, feed and muck
- Wash down. Pressurised spraying down the shed
- Detergent. A high foaming detergent such as Alkaliene should be used to break down fat lipids present in the faeces and remove encrusted muck
- Disinfection. A Defra approved disinfectant used
If you have a red mite issue, Interkokask used at a rate 3% is very powerful. Its unique formula contains chlorocresol and has shown excellent effectiveness used at an approximate rate of 11 litres in 350L of stock solution
Intercid was tested and shown to be very effective against salmonella. It is cheaper than Interkokask and is a very good base product to use. The increased concerns over salmonella infection in older birds makes it important to do as much as possible to reduce the challenge, as well as looking at ways of improving the bird’s resistance to salmonella as it gets older
- Secondary disinfection. The use of Halamid fogging as a 10% solution as the final stage
Our veterinary and field services teams can provide advice on bespoke bespoke cleaning programmes to tackle specific on farm disease challenges, including a turnaround fogging service.