Infectious agents of poultry are a threat to poultry health, at times and have significant human health, social and economic implications. In poultry production, especially under intensive conditions, prevention is the most viable and economically feasible approach to the control of infectious agents. Biosecurity procedures should be implemented to prevent the introduction and dissemination of infectious agents in the poultry production chain. Biosecurity will be enhanced with the adoption and implementation of the principles of Good Agricultural Practices and the Hazard Analysis Critical Control Point (HACCP) system.
Biosecurity refers to actions and measures implemented to prevent and control the introduction and spread of infectious diseases. Good biosecurity is vital to the successful performance of any poultry production system (DAF&F, 2009). Biosecurity protocols can apply to several sections of a poultry production system including personnel and visitor requirements, restricting contact between poultry and other animals, proper shed sanitization, equipment, and vehicle disinfection, and thorough water treatment. Biosecurity protocols on poultry production systems aim firstly to reduce the potential introduction of infectious diseases on the farm. If an infectious disease is introduced and becomes established, the protocols aim to limit the spread of the disease within and between farms. Proper implementation of biosecurity protocols maintains good health and welfare of poultry on farms and reduces financial losses by decreasing the frequency and magnitude of infectious disease outbreaks (Nespeca et al., 1997).
Major routes for Disease and Pathogen transmission
Poultry: Transfer of birds from the production area to other production areas and dead bird disposal.
Other animals: Wild birds, feral, domestic animals and birds, including other livestock, pets, insects, rodents-rats, mice, etc.,
People: Farm personnel and family members living on-site; contractors, maintenance personnel, neighbours, serviceperson, and visitors, the disease can be transmitted by, for example, hands, boots, clothing, dirty hair, etc.
Equipment: Feeders, waterers, nests, debeakers, vaccinators, sprayers, burners, etc.
Vehicles: Feed Trucks, Product and waste collection vehicles.
Air: transmission as an aerosol or dust.
Water supply: Water supplies may become contaminated with faeces of avian or other animal species.
Feed: Feed may be contaminated by the raw materials used, post-production and during transport, or by exposure to rodents and birds on the property. Bacteria and mould in poor quality or damaged feed may also be a concern.
The location and structural biosecurity principles are to be followed at the very beginning while setting up the farm. Operational biosecurity measures, in general, revolve around three basic principles viz:
Traffic control and
I. Farm location and Design
Poultry farm maintaining the valuable germplasm should ideally be located at a well-isolated site away from other farms. It should be located away from water bodies that can be a source of water for wild birds and animals and these are ultimate may become a source of infection to birds maintained on the farm. Ideally, it should be located at least 1-2 km away from other commercial facilities.
The perimeter of the farm and hatchery must be secured with a boundary wall and other measures. The production area must have a perimeter fence or otherwise well-defined boundary (e.g. vegetation) establishing a clearly defined biosecurity zone.
Major critical points to ensure biosecurity must be displayed in regional and local languages at every different species unit.
Signboards indicating ‘Biosecurity area’, ‘visitors are not allowed’ are to be displayed at breeding stocks and hatcheries of each species.
The farm should be designed in such a way that it has sufficient ventilation and should have access to sunlight. This will be necessary for reducing the build-up of infectious agents in poultry houses apart from reducing the stress of accumulated gases.
The direction of the long axis: This depends on the geographical location of the farm. If the farm is located in the cold region then the direction of the long axis should be North-South.
II. Restricted access to Birds
It means restricting access to a farm by employing fences and enclosures which creates a barrier between clean areas where poultry are kept and outside environment and it is the most important biosecurity measures for restricting the source of infection away from the farm and even from the infected to another non-infected farm. Movement restriction should be applied both at the farm as well as at shed level. CCTV, if required, on the whole campus to monitor & supervise the activities on the campus is recommended.
III. Isolation and Quarantine of new birds
Isolation and quarantine of new birds are necessary in a separate place and enclosure so that infectious agents that maybe they're in the newly introduced birds may be detected before the introduction of these birds with other flocks.
IV. Cleaning and Sanitation
Effective cleaning and disinfection is an essential component of good hygiene and thus one of the key biosecurity measures for disease control. This should be carried out from time to time to reduce the build-up of pathogenic organisms and a disinfectant known to be effective against a large range of pathogens should be used regularly for prevention of ingress of the infection.
Approved disinfectants like chlorine dioxide and peracetic acid for disinfection or sterilization may be used.
Farm equipment entering the farm, cleanliness of personnel on the farm, disposal of dead birds and poultry manure and sanitizing the drinking water should be paid attention.
The area around poultry sheds should be kept clean from vegetation, food waste, plastic bottles, glass bottles, tins or drums.
Water testing should be done at regular intervals.
Proper ventilation with adequate airflow in all sheds is recommended.
Regular testing of Microbial load at different places is recommended.
V. Personnel hygiene
Specific overall clothing for employees must be provided.
Wash hands thoroughly before and after entering the farm area. Washing of hands can be done with soap or detergents with a contact time of 10 minutes.
Wear clean clothes while working with birds on the farm. The clothes should be washable with laundry detergent.
Since disease in poultry can be transmitted easily through boots, therefore, boots should be used after cleaning and disinfection.
When the care personnel needs to attend to chickens or other poultry (e.g. collecting eggs, feeding or watering, change of bedding or repair of fencing material), a change of clothes/ boots is required.
Medical check-up of all workers coming in contact with livestock and feed should be done.
VI. Hygienic disposal of poultry manure
Poultry manure should be left undisturbed for at least 90 days and then can be used as fertilizer. High-risk farming practices such as the use of contaminated water and recycling of poultry waste without treatment should be stopped.
The effluent generated from poultry processing of manure can also be disposed of after treatment with acids such as hypochlorous acid 2% or citric acid 0.2% or with alkali treatment such as Sodium hydroxide 2% or sodium carbonate anhydrous 4%.
VII. Disposal of dead birds
Dead birds should be removed quickly and properly, to ensure no contact with other birds which will help remove the source of infected foci to poultry as well as to handlers. The best way to dispose of dead birds is by rendering, burial or incineration.
VIII. Feed safety
Feed Safety objectives make use of principles that relate to animal health, farm practices, and human food safety objectives for products of animal origin. Particular emphasis should be on the types of feed used concerning feed borne animal diseases caused by infectious, chemical agents and on the relationship between animal feed and zoonotic food borne diseases. To produce safe animal feed, a pro-active control system is advocated. This approach has been very successful with human food and involves the use of Good Manufacturing Practices (GMP) and the Hazard Analysis Critical Control Point (HACCP) concept as the main tools.
Feed and feed ingredients business operators and other relevant parts of the industry should practice self-regulation to secure compliance with required standards for procurement, handling, storage, processing, distribution, and use. Operators have full responsibility for implementing systems for quality control. The Competent Authority should verify that process control systems and safety standards achieve all regulatory requirements.
IX. Medication / Vaccination of birds
The birds should be provided certain medicines and essential vaccines regularly, which can boost immunity such as vitamins, trace minerals, and proteins. Deficiency of these will not only lead to decreased production but there will be more chances of getting an infection in a flock with a low level of immunity. Anti-stress medication during hot weather and other stressed conditions may be given (Scott et al., 2018).
X. For High risk / Alarming situation
Self-quarantine upon the suspicion of an infectious disease - No movement of poultry, eggs, dead carcass, manure, farm machinery, and equipment should be allowed within the affected shed area and to outside/other sheds area.
Immediately adopt enhanced biosecurity protocols for unaffected sheds.
Treat dead birds as infectious material and dispose of accordingly.
Dedicate specific employees to the affected shed(s).
The farm personnel should wear protective clothing all the time inside the farm, including face-masks & gloves, gumboots.
Follow strict personal biosecurity procedures while leaving the farm.
Immediately restrict on and off-farm access by locking gates.
Suspend all unnecessary traffic – no vehicle should be allowed to ply in & out on the farm. A personal vehicle should be left outside the farm premises.
Disinfection procedures should be strictly applied at the entrance and around the premises.
Immediate reporting of the unusual mortality & sickness of the birds in the farm to the nearest Government Veterinary Officer/ Ministry.
XI. Documentation and Recordkeeping (Indicative list)
Outlay/map of the entire farm with clear demarcation of clean and dirty areas with unidirecti