Infectious diseases, such as Avian Influenza (AI), pose a constant threat to commercial poultry production worldwide, and the Canadian poultry industry is no exception. Outbreaks of Highly Pathogenic Avian Influenza (HPAI) in British Columbia and Infectious Laryngotracheitis (ILT) in Ontario in 2004, plus the detection of several low pathogenic AI strains in waterfowl across Canada in 2005, demonstrate that the risk of infection with serious diseases, although low, is constantly present. The poultry industry in Ontario must, therefore, constantly protect itself against threats such as AI and ILT. Implementing a sound “biosecurity” program that is both practical and based on scientific principles is an inexpensive, yet highly effective tool against such contagious and costly diseases.
Sources of Infection
Diseases can be introduced to a commercial poultry flock by many different routes. The most common sources are:
* wild birds, rodents and domestic animals (e.g. cats and dogs)
* contaminated people (e.g. hands, clothing, footwear, hair)
* contaminated poultry equipment (e.g. hauling crates, catching equipment, feeders and waterers)
* contaminated water source
* contaminated vehicles and other farm equipment (e.g. manure trucks and spreaders, tractors, feed trucks)
* infected neighbouring flocks (commercial or backyard) and live bird markets.
The common thread among the different routes of introduction is exposing poultry to infected birds, either directly or through exposure to contaminated people or equipment. The aim of biosecurity is to create barriers between your birds and the many sources of contamination.
Major Components of a Good Biosecurity Program
An effective biosecurity program is based on two main concepts: exclusion (keeping the disease out of the flock) and containment (if it has been introduced, preventing its spread within the premises or to other uninfected flocks). Because the risks are different for each poultry operation, consult your veterinarian to customize the biosecurity program to your specific situation. However, there are certain key components, addressing both exclusion and containment, which should be included in any biosecurity program. These are isolation, traffic control, and cleaning and disinfection (C&D).
1. Isolation: Preventing exposure of your poultry to viruses and other disease agents is the first step. The following recommendations are barriers designed to keep your birds isolated from sources of disease introduction.
* Install a sign at the farm gate and at the entrance of each poultry house to instruct unauthorized people not to enter the premises/houses. Lock all doors to the poultry houses at all times in order to restrict access.
* Minimize contact with other poultry, including neighbouring backyard flocks. Do not share any farm equipment, if possible. Do not allow any farm employees, including manager/owner, to keep backyard or pet birds, nor attend live bird shows or markets.
* Apply a strict rodent and insect control program and monitor its efficacy regularly. Keep vegetation and debris cleared around poultry houses, as these will attract rodents.
* Avoid situating poultry houses near ponds. These will attract wild birds and waterfowl that can carry diseases.
* Ensure all poultry houses are wild bird proof. Screen all inlets and fans and plug or repair any gaps and holes in the structure. Monitor buildings regularly and repair immediately. Immediately clean feed and water spills in the farm environment, especially outside poultry houses.
* Do not allow dogs and cats inside poultry houses at any time.
* Collect routine mortalities several times a day and dispose of appropriately. It is important to prevent access to dead birds by wild birds and other animals. In consultation with your veterinarian, establish a proper carcass disposal protocol. If rendering is the method of choice, keep daily mortalities in a designated freezer/cooler. On the scheduled pick-up date, transport dead birds in a covered rodent/ predator proof container to the roadside or another designated site that is far from the barns. Clean and disinfect all used equipment (such as barrels) at the end of carcass pick up.
2. Traffic and visitor control: Since it is not possible to completely isolate the flock and the farm, it is essential to follow proper protocols for movement onto and within the operation.
* Park all vehicles in a designated area far from poultry houses and away from farm vehicle traffic areas.
* Allow only certain authorized and necessary personnel to enter poultry houses. It is important that visitors wear clean coveralls (disposable is preferred), mask, hair protection (cap) and disposable footwear (if boots are used, have designated boots for each barn and thoroughly clean and disinfect after each visit). Use disposable gloves and wash hands with appropriate hand soap or sanitizer before and after each visit. Regular necessary visitors such as meter readers, fuel and feed delivery drivers and service personnel, must also use all necessary clothing and footwear as mentioned.
* Use separate dedicated clothing and footwear for each poultry house.
* Keep a record of all visits in a designated logbook. Record names of the individuals, the nature of their business and their contact information.
* If using a footbath, follow label instructions for the disinfectant to ensure appropriate concentration and refill as necessary. A dirty footbath increases the risk of infection.
* A shower-in, shower-out policy for all visitors and employees is the most efficient approach. (This may be more practical for breeder and primary breeder flocks.)
* Catchers must use separate clothing, footwear, mask and hair gear for each farm. Clean and disinfect catching equipment after each loading and before entering the next farm. This is extremely important if only part of the flock is shipped to the processing plant (thinning out or partial pick up).
* It is preferred to have an all-in, all-out system (single age flock at any given time). If this is not possible, always visit from youngest to oldest and from healthy to sick flocks.
* Always keep clothing and footwear used by the farm manager and employees on the farm separate from those worn off farm. Do not allow managers and employees to visit other poultry farms.
3. Cleaning and Disinfection (C&D): While isolation and hygiene practices are very effective, it is inevitable that some contamination of the farm environment will occur. Good biosecurity also prevents diseases from leaving your property. These recommendations will limit the spread of the contamination within the premises, and to other premises.
* Avoid borrowing or lending farm equipment. If equipment is shared, clean and disinfect before and after use. Complete removal of any organic material before disinfection is very important.
* Proper sanitation of drinking water is a must. There are different methods of water sanitation. If applying chlorine, monitor the level of active chlorine and water pH for effective chlorination. Clean and disinfect water lines completely between flocks to avoid build up of biofilm and slime that can harbour germs and inactivate some disinfectants. Consult with your veterinarian to implement an effective water sanitation program. If using pond water, proper sanitation of the water is extremely important as waterfowl and wild bird excretions can contaminate it.
* It is preferred to wash and disinfect (complete C&D) poultry houses between flocks. It is important to apply disinfection only after barns are completely cleaned from litter/debris, pressure washed with warm water and detergent and allowed to dry. Consult with your veterinarian for a complete detailed C&D program, as the appropriate steps must be performed in the correct order for optimal results. If there is a history of an infectious disease in the previous flock, it is strongly recommended to perform a complete C&D between flocks regardless of the time of the year.
* If possible, manage your manure on-farm, preferably by composting. This is particularly important for manure from a diseased flock. Keep the temporary on-farm storage site well away from any barn. Ideally, have the manure in one pile and cover to protect from wild birds and water (while following all other provincial regulations). If manure is hauled at the end of each flock, manure trucks should be damped and tarped before leaving the farm.
Biosecurity is Everyone’s Responsibility
Keeping serious diseases out of Ontario or out of the commercial poultry industry is a shared responsibility, from government, to industry associations down to the individual producer. Nevertheless, the farm is the last line of defence and it is at the farm level where outbreaks are most effectively controlled or prevented. As a producer, it is extremely important to:
* Be aware of general clinical signs of disease in birds. Early detection, by recognizing the signs of infectious diseases and taking the appropriate action ASAP, can greatly limit the impact of a disease outbreak and allow for a faster return to normal operation. Signs that may indicate a significant disease outbreak include (but are not limited to):
- high mortality
- drop in egg production
- reduced feed/water consumption
- respiratory and nervous signs.
* Seek veterinary assistance if your poultry flock looks sick or abnormal. Your veterinarian will submit the appropriate diagnostic samples to the Animal Health Laboratory for a proper diagnosis.
* Establish and maintain an acceptable biosecurity program at your farm in consultation with your veterinarian. Review and revise the biosecurity program continuously.
* When a poultry disease is suspected in the area, be prepared, in consultation with your veterinarian, to heighten the level of biosecurity (enhanced biosecurity).
The practicality of a biosecurity program depends on the cost, relative risk and common sense. However, it is the most cost-effective available tool, considering the potentially devastating consequences of a significant disease outbreak.
Diseases such as Avian Influenza can be introduced to commercial poultry premises by many different routes, including people, equipment, wild birds, rodents, litter, carcasses, feathers, and possibly by wind or aerosol spread. By implementing and diligently maintaining a sound biosecurity program, the producer can put in place the multiple barriers necessary to minimize the risk of introducing diseases to the flock or spreading them to other flocks.
By Babak Sanei - Lead Veterinarian, Disease Prevention Poultry/OMAFRA; Paul Innes - Lead Veterinarian, Provincial Biosecurity/OMAFRA