Biosecurity

Figure 16.65 Disease causing organisms on poultry farm Disease-causing organisms on a poultry farm

What is Biosecurity?

Biosecurity plays an integral part seen as your first line of defence to prevent or control the introduction and spread of infectious agents, such as viral, bacterial, and fungal diseases, into a flock of birds.

Biosecurity is an integrated approach encompassing policy and regulatory frameworks to analyse and manage risks in the areas of animal health and food safety, including associated environmental risks. The liberalisation of global trade in agriculture since the 90s has brought in many challenges apart from opening up new avenues for growth and diversification. Pests do not recognise geographical boundaries and liberalisation of trade has opened new routes for animal diseases and pests through the import of animal (livestock, poultry) and animal products. Many of the pests have the potential to establish and cause serious economic losses. An integrated biosecurity programme is an application of logical and sound principles specific to:

an enterprise
monitoring of disease status
evaluation of ongoing poultry farm operations continuously to contain the diseases at a bare minimum level.

The farms should strive to maximise the benefits achievable through effective biosecurity and to be consistent with HACCP (Hazard Analysis, Critical Control Points) principles which can be developed easily.

A. Farm Biosecurity

Farm biosecurity is a set of measures designed to protect a property from the entry and spread of pests and diseases. Farm biosecurity is your full responsibility making sure that every work colleague or visitors implement sound biosecurity measures on the farm.

A sign should be put up to demarcate the biosecure area.

Levels of Biosecurity

There are three levels of biosecurity:

Conceptual Biosecurity
Structural Biosecurity
Operational Biosecurity

Threats to the different levels of biosecurity and the associated risk management components.

Three levels of biosecurity	Threats to biosecurity	Bio-risk management components of biosecurity
Conceptual biosecurity	Invasive species	3 components of protection
Structural biosecurity	Pests	Physical security
Operational biosecurity	Disease	Personal reliability
	All of these cause harm to the agricultural production environment, community and human health.	Information Security

Conceptual biosecurity are measures considered whilst planning a poultry business such as poultry housing and the following points are thus important.

Poultry farms should be 1 km away from another poultry farm.
Breeder farms should be kept away at least 3 km away, due to the sensitivity as compared to layers or broilers.
The distance between one poultry house and the next should be 100 metres to maintain ventilation on the farm.
Sufficient distance must be maintained for hatcheries, abattoirs, and burial pits to avoid cross-infection.
Poultry farms should be close to roads, however caution must be taken into account concerning highways. Air pollution from highway transport could influence the flock to suffer from respiratory disease.
Check water supply as it plays a vital role in biosecurity via the spreading of waterborne diseases in the flock, which can lead to heavy losses.

Structural biosecurity are measures to keep poultry birds safe on the premises. Important points to follow:

Stock theft is a huge economic problem in poultry production due to no fencing, security guards around the farm site
It is thus important to establish tight fencing around the farm and the poultry housing to avoid theft of chickens and equipment. This been said is to keep unwanted visitors off the premises.
Try to plant trees near the poultry house to help maintain temperature, trees also assist to reduce micro-environment temperature however also poses a threat to the flock. The threat is that trees tend to fall onto the poultry houses in heavy wind and storms may attract wild birds which transmit deadly diseases such as AI (Avian Influenza).
Water sources attract wild birds, can cause havoc in your flock.
Wire nets attract wild birds, cover all holes in the wire nets
Rodents proofing of the poultry housing, extremely vital to biosecurity. Ground around poultry house must be level, grass cut down and kept neat and free to keep surveillance on rodents and snake activity.
Dead birds must be disposed properly and away from the poultry house. A burial site far away from the poultry house (burn the carcasses to prevent spread of infections).
Facility for vehicle disinfectant and change rooms for staff and visitors to be established to avoid entry of outside infections.

Functional Biosecurity is operational biosecurity measures related to the day in day out activities on a poultry farm.

Important points to follow:

Different feed stations for each poultry house (day old chick, grower and adult flocks) to avoid cross infection, limit the entry in the different houses.
Staff should change their clothes, and wear suitable personal protective equipment (PPE, gloves, mask, hair net)
Staff should take showers at entry level itself.
Vehicles entering the farm from the outside should be washed down with disinfectant before entering onto the premises.
Every farm should have operational manuals or SOPs (Standard Operating Practices), and HACCP manuals to deal with the emergencies.
Disinfection of each poultry house after batch of flock has left followed by resting periods of 14 days which is to mandate to destroy contamination pathogen cycle.
Daily or weekly removal of equipment for cleaning and disinfection is highly recommended unless it is automatic and can be done through water disinfection
Foot baths is mandatory before entering any poultry house on site.
Vaccination and other medication should be done with minimum disturbances to the flock.
Fixed schedules for vaccination, feeding, egg collection and AI.
Vaccination programs: Broiler and Breeder Layer
Pest control and rodents, wild birds, snakes, predators one must give special attention, take precautionary measures as early as possible. Destroy flies with pesticides and hang up fly buckets around the corners of each poultry house.
Rat traps need to be established as well.
Morbidity and mortality records important to implement frequent control measures.
Changes in management according to season, may increase morbidity thus mortality.
Record keeping, proper disposal of dead birds which act as a reservoir for deadly pathogen diseases.
Litter management, vital role to operational biosecurity is concerned.
Wet litter created ammonia (˃25ppm), which causes breast blisters and respiratory problems in the flock.
Water quality must be maintained. The physiochemical quality standards for drinking water are listed below:
pH 5.5 to 6.5
Hardness (TH), Calcium level 10-15°TH
1° TH = 4 mg calcium per litre
Nitrates ˂50 mg per litre
Iron ˂0.2 mg per litre
Sulphates ˂300 mg per litre
Chlorine˂250 mg per litre

Biosecurity Guidelines

Infectious disease comes from many different vectors such as viruses, parasites, fungus or bacteria and is transmitted in many different ways by people, animals, equipment or vehicles.

In order to protect your flock of poultry from infectious diseases you need to limit who and what comes in contact with them. You will also need to obtain written biosecurity protocols from your processor, feed mills and hatcheries.

With recent avian influenza outbreaks that occurred in May 2017, the SA Poultry Association has enacted an interim rule that farmers must have a written biosecurity plan on site in order to ensure implementation will run smoothly between the flock owner and the growers.

There are different size operations to fill out a plan, sign, date it and keep it on file in the event of such another outbreak. Documentation on a farm can prove a plan was in effect even if the farm is located inside a disease control zone and is worth the time considering the possible financial implications of an outbreak.

Biosecurity is a practice designed to prevent the spread of disease onto your farm. It is accomplished by maintaining the facility in such a way that there is minimal traffic of biological organisms (viruses, bacteria, rodents, and so forth) across its borders. Biosecurity is the cheapest, most effective means of disease control available. No disease prevention programme will work without it. Biosecurity is the term used to describe an overall strategy or succession of measures employed to exclude infectious diseases from a production site.

Standard Operating Procedures

Standard operating procedures show you how you as a farmer carry out your daily farming activities. This demonstrates the care that you take with your chickens and it guides you on how you are working on your farm, thus your staff will need to follow the farms standard operating procedures.

Make sure you and anyone who works with you on the farm understands and uses the good management practices that will protect you and your flock.

Your SOPs must include the following:

Code of conduct covering bird welfare
Farm staff biosecurity protocols and programme
Supplier or visitor biosecurity protocols
Access procedures for the CAZ and RAZ
Pest control programme
Poultry house cleaning and disinfection procedures
Manure management
Mortality management
Farm emergency or quarantine procedures
A training record must be kept for each employee as this record can simply be a sign off that they have read and understood the SOP’s.
Staff must be monitored and receive additional training, if necessary
Anyone who comes on the farm and handles the chickens must have signed the code of conduct covering the bird’s welfare.

The Importance of Biosecurity

Taking measures to protect your birds from harmful biological agents such as viruses, bacteria, parasites, fungi, protozoa. No single disease programme will be effective without taking proper biosecurity measures.

Basic Principles of Biosecurity

Keep visitors to a minimum
Keep a register all your visitors – for traceability of diseases entering the farm.
Wash your hands before and after coming into contact with live poultry.
Provide disposable boot covers and disinfectants for foot baths for anyone having contact with your flock.
Change clothes before entering the poultry house, incubation, hatcheries and before exiting the properties.
Clean and disinfect tools or equipment before moving them to a new poultry facility.
Look for signs of illness (warning signs of infectious bird diseases).
Report and record sick birds
Contact your veterinarian immediately for consultation. If you do not have a poultry veterinarian one will be allocated to you.

Farm Diagram

Make sure you have a farm diagram that includes the location of your controlled access zone (CAZ) and restricted area (RA) as well as manure storage, back-up generator, feed bins, water tank and other production –related areas. People, companion animal pets, rodents and other animals can be all disease carriers. You as the farmer need to create two zones of defence on your farm.

A CAZ around the outside of the poultry house and the range area. A RA that includes the inside of the poultry house where the birds are actually located.

This doubles the safety of your flock of poultry: once zones are in place, make sure everyone agrees to the rules set out on the farm.

Clearly identify the access or entry points to the CAZ by a sign or physical barrier so that people who are entering the farm know where they are not allowed to have access.

Install a physical barrier such as a fence or a gate. The sign is used and should read “Biosecurity in Effect” and include a phone number for visitors to call.

If you have production facilities without people living on the premises, you must have gates or barriers that are lockable in times of heightened biosecurity.

Visitors who come to your house and have no connection with poultry production on the farm still represent a risk, however limited. The CAZ should be designed so they can get to the house without going through it.

You as the farmer should have a visitor parking area outside the CAZ.

Only let vehicles that are necessary to the work of the farm into the CAZ – including those delivering fuel, litter, feed, chicks or other materials and those that are transporting birds or manure out of the poultry houses. No other vehicle should enter the CAZ area.

Inspection:

All chickens kept in the holding must be inspected at least three times a day.

Special attention should be paid to signs indicating a reduced level of animal welfare and or animal health.

Cleaning and Disinfecting of Poultry Houses

Create a plan: Determine times, labour, and equipment requirements before depleting the farm.
Control insects: Spray the interior of the house with a locally recommended insecticide.
Remove dust: Remove all dust and cobwebs from the interior surfaces and equipment.
Pre-spray: Spray detergent solution throughout the house interior to dampen dust down. (VIRUKILL)
Remove equipment: Remove all equipment from the house and raise automatic feeders and drinkers.
Remove and dispose of litter: Litter must be removed and disposed of properly.
Wash and rinse: Use a pressure washer with detergent that is compatible with the disinfectant. Rinse with hot water.
Clean water and feeding system: Empty clean, disinfect systems, and flush water lines. Use the Virukill Fumigate feeding system where possible.
Disinfect: Use approved disinfectant that is effective against specific poultry bacteria and viruses) (Spray in the house), disinfectant (Use Virukill Disinfectant)
Fumigate: Fumigate as soon as possible after disinfectant surfaces should be damp and house warmed. Seal poultry house for 24 hours ventilate for entry. Repeat after litter has been spread.

Foot Bath Procedures

Who: Rearing sites.

Why: The reason for using a foot bath is to have clean boots, free from any organic material (manure) to prevent:

Disease being carried into a house from outside (wild bird droppings) or from one house into the next house.
Disease being carried out from a diseased house to outside or another house.

When: Every time a person enter or leave a house, they must dip and clean their feet in the foot bath situated at the entrance door of the house. Nobody is allowed to bypass it.

How: Follow the procedures to enter and exit.

A. Procedure to Enter

Step into foot bath
Wipe feet on scratch mats which are in the foot bath
Check boots underneath before stepping out of foot bath to see if it is free of organic material. If not clean, use brush hanging on wall to clean your boots
When boots are clean step out of foot bath and enter house

B. Procedure to Exit

When exiting a house, use same procedure as when you entered.

C. Cleaning

The foot bath must be drained and cleaned daily first thing in the morning
Fill foot bath with 100 litres of clean water (4 x 25 litre scopes)
If foot bath gets excessively dirty during the day, clean it again
Chemical to be used in foot bath: Virukill
Dosage: 1:100 (for 100 litres of water

Sanitation Practices

Thoroughly clean and disinfect poultry feeders, drinkers and waterers on a daily basis. Provide clean fresh water.
Thoroughly clean and disinfect poultry housing equipment at least every day.
Have a dedicated pair of boots for entering your poultry area. One pair of boots per poultry house (mark each pair with a colour add the same colour to your poultry house. Keep a fresh tray of disinfectant by each poultry house to dip foot wear at the entrance of the poultry house. Tray must be cleaned out every day to prevent spread of further diseases.
Avoid sharing equipment and supplies with other flock owners.
Do not allow water to stagnate as it attracts mosquitos which can transmit diseases.
Wash hands before and after handling poultry.

Deadstock Disposal

All mortalities should be disposed of in line with local health regulations. Dead birds should be removed by authorised personnel wearing PPE, any culling required for the purpose of bird welfare should be completed by trained authorised personnel. All culling must be done complying to local legislation and in a humane and biosecure way at all times.

Correct methods of dead bird disposal and their advantages are given below:

Methods for the disposal of dead stock.

Method	Advantages	Disadvantages
Disposal Pits	Inexpensive to dig and tend to produce a low odour	Can be a reservoir for diseases and require adequate drainage Groundwater contamination
Incineration	Does not contaminate groundwater or produce cross-contamination with other birds when the facilities are properly maintained Litter to be removed from the farm	More expensive and does produce air pollution Ensure that there is sufficient capacity for future farm needs Ensure that carcasses are burned completely to whitish ash
Composting	Economical and managed properly, will not contaminate groundwater or air	If not done to the correct temperature, live and viable diseases may be present on the farm
Rendering	There is no-on farm disposal of dead birds Requires minimal capital investment Produces minimal environmental contamination Materials can be turned into feed ingredients for other appropriate livestock	Requires freezers to keep birds from decomposing during storage Requires intense biosecurity measures to ensure that personnel do not transfer diseases from the rendering plant to the farm