Salmonella: test your broiler flock chickens
Source: gov.uk (2025-11-10)

When and how to test for salmonella if you breed broiler chickens, and what happens if a flock tests positive. Testing is part of the salmonella national control programme (NCP).

When you must test for salmonella

You must test for salmonella if you keep 2,000 or more broiler chickens at any time in 12 months.

Broiler chickens are birds kept to produce meat for human consumption, including slow growing breeds and organic production.

You must sample each of your individual flocks. A flock is a group of birds that shares the same air space, for example a chicken house or range.

Testing is required by law and is an essential part of the national control programme (NCP) to reduce salmonella in poultry and protect animal and public health.

You do not need to test your flock if you:
- produce birds for private domestic use (the birds do not enter the market)
- supply the consumer direct (such as through farm-gate sales or local retailers)
Before you test for salmonella

Register places where you have a hatchery or keep poultry

In Great Britain (England, Scotland and Wales) you must register each premises where you keep poultry (even if you only keep a single bird).

In England and Wales, register as a bird keeper with APHA (https://www.gov.uk/government/collections/register-as-a-bird-keeper).

In Scotland register on the Scottish Kept Bird Register (SKBR) (https://keptbirdregister.service.gov.scot/).

In Northern Ireland you must register all poultry flocks on the Northern Ireland Poultry Register (https://www.daera-ni.gov.uk/publications/bird-registration-form). This includes a single backyard bird. The only exception is if it is a pet bird that lives in the owner’s house.

Ask your vet or a NCP-approved laboratory for advice

If your flock is in Great Britain, you must use a laboratory approved by APHA (https://www.gov.uk/government/publications/salmonella-in-poultry-testing-laboratories-in-the-uk).

If your flock is in Northern Ireland, you must use a laboratory approved by DAERA (https://www.daera-ni.gov.uk/articles/salmonella).

Your vet or laboratory approved to undertake NCP testing can help you:
- create sampling plans
- train staff to take the samples correctly
- get the sampling kit you need
- work out how many flocks you have
You must take samples from all the flocks at your premises. These samples must include all subdivisions within houses and all houses or mobile units sharing the same range area. There are guidance documents available from APHA regarding the definition of a flock in complex housing systems.

If you need help to work out how many flocks you have, ask your vet.

If you still need help to work out how many flocks you have, ask APHA (https://www.gov.uk/government/organisations/animal-and-plant-health-agency/about/access-and-opening) or DAERA (https://www.daera-ni.gov.uk/contact).

When to collect samples

Test flocks before slaughter

All flocks being slaughtered for human consumption must be tested before slaughter.

You must take samples for birds aged:
- 81 days or less, within 3 weeks before slaughter
- 82 days or more, within 6 weeks before slaughter
You must take samples from organic birds within 6 weeks before slaughter. This only applies if your broilers have organic certification from an UK approved organic control body (https://www.gov.uk/guidance/organic-food-uk-approved-control-bodies).

You should time collection of your samples assuming that there could be a positive result identified by the lab you send your samples to for testing. If so, your lab must send material to the APHA or DAERA lab for official testing.

This official testing cannot begin until the bacteria and required supporting information has been received from your laboratory. Once received, testing can take up to 12 working days for certain strains of salmonella so that they can be accurately identified. Accurate identification is important as only certain strains of salmonella need further official action to be taken. You will be informed by APHA or DAERA of the final result as soon as it is available.

If you choose to sample too close to the slaughter date and a positive result requires official testing, you may not have the final results ready to send with the birds to the slaughterhouse on your originally planned slaughter date. That may mean they must be treated as of unknown salmonella status by the slaughterhouse, or that you have to consider postponing their slaughter until you have received the final result.

Avoid taking samples after giving antibiotics

A vet may prescribe antibiotics (also known as antimicrobials) for various purposes, but not as a specific method to control salmonella in poultry.

Whatever age your birds are when collecting samples, avoid taking samples while, or shortly after, giving your broiler chickens antibiotics that affect salmonella.

Consult your vet for advice if you need to take NCP samples within 14 days of the last dose of antibiotics administered to your chickens. Not all antibiotics affect NCP testing.

APHA or DAERA could consider your flock to be positive for salmonella if the laboratory suspects that there may be disinfectant or antibiotics affecting your samples.

To find out when you can sample after giving antibiotics, ask the vet who prescribed them.

If you think a proposed antibiotic treatment may compromise your upcoming NCP salmonella testing, you should collect your NCP samples before starting to administer the medication if within the required sampling window prior to slaughter. Take care that any subsequent NCP samples are also re-scheduled to reflect the new sampling date.

How to collect boot, dust and hand-held swab samples

You must take samples from all the flocks at your premises. Include:
- all subdivisions within houses sharing the same airspace
- all houses or mobile units sharing the same range area
From each flock, you can either collect:
- 2 pairs of boot swabs (#boot-swabs)
- one pair of boot swabs (#boot-swabs) and one dust sample (#dust-sample)
- 2 hand-held faecal swabs (#faecal-swabs) - for flocks with fewer than 100 birds per house
Prepare to take samples

Gather all the equipment you are going to need before you go into the poultry house to prevent contamination before, during and after sampling. Take care to avoid cross-contamination if you keep other animals (especially other poultry, pigs, sheep, horses, cattle or pets), as well as from wild birds.

How to collect boot swab samples

You will need:
- disposable plastic over boots – plastic over-boots prevent any contact between disinfected or contaminated boots and boot swabs which could affect your sample
- disposable plastic gloves
- leak-proof sealable bags or sample pots
- packaging for sending your sample bags or pots to the laboratory
- boot swabs – these must be absorbent enough to soak up moisture - you can also use tubegauze socks or pre-moistened commercial swabs (it is best to use commercial sampling kits with sterile, pre-moistened swabs and then you do not need to carry water)
- tap water or bottled still water for moistening boot swabs – do not use sparkling water or water treated with antibacterial agents or acids
You should:
- only sample the inside of the house
- avoid sampling the areas just inside of doors and pop holes as they may have been contaminated by material from outside
- take boot swab samples from the existing litter – do not put new litter down in the 2 days before sampling
- moisten the swabs with water before you take samples – you can do this by putting the swabs into a grip-seal bag and pouring water onto them inside the bag and then shaking the bag
To collect the samples:

1. Put on new disposable gloves - do not use hand sanitiser and make sure you do not contaminate them with disinfectant as it could affect your sample.

2. If not already moist, moisten the boot swabs with tap water or bottled still water.

3. After walking through disinfectant foot-dips and entering the bird area, put on plastic over-boots, then put on the first pair of boot swabs. The plastic over-boots prevent any contact between disinfected or contaminated boots and boot swabs. The presence of disinfectant or other bacteria on the swab may prevent identification of salmonella by the laboratory or result in a false positive test result if boots are already contaminated by salmonella.

4. Take at least 100 steps in each pair of boot swabs – if collecting:
- one pair of boot swabs, walk around the entire house
- 2 pairs of boot swabs, walk round half the house in each pair
5. Shuffle your feet on the floor as you walk to pick up as much material as you can.

6. If the house is divided into several pens, make sure every pen is included in the sampling.

7. Include all pens or mobile units used by the flock in the sampling. On most farms with multiple mobile units per flock, hand-held swabs for collecting faeces are the best sampling option to use to avoid inadvertent contamination while sampling.

8. When you have finished sampling, take the boot swabs off and carefully turn them inside out so that the faeces you have collected stay on them.

9. Put all the boot swabs in one sample bag or pot.

10. Label each container carefully, ready to send to the laboratory.

How to collect dust samples

You can collect a dust sample to use in combination with one pair of boot samples.

To take the dust sample, choose one of these methods:
- collect 100g of dust from multiple places in the house and put this in a pot or bag (this is a ‘dust sample’)
- use one or more moistened fabric swabs with a total surface area of at least 900cm2 (this is a ‘dust swab sample’)
Avoid collecting dust from feeding systems.

You must package dust samples separately from boot swabs.

To collect a dust sample you will need:
- disposable plastic gloves
- leak-proof sealable bags or sample pots
- packaging for sending your sealable bags or sample pots to the laboratory
To collect dust samples:

1. Put on new disposable gloves - do not use hand sanitiser and make sure you do not contaminate them with disinfectant as it could affect your sample.

2. Collect 100g of dust from multiple places in the house. For example, from outlet vent baffles, beams, pipes, ledges, partitions, nest boxes in the house and put the dust in a pot or bag. If your dust sample is less than 100g the lab will not test it, so be sure to collect a sufficient amount of dust.

To collect a dust swab sample you will need:
- one or more swabs - the total surface area of the swabs must be at least 900cm2
- tap water or bottled still water for moistening swabs, if not pre-moistened - do not use sparkling water or water treated with antibacterial agents or acids
- disposable plastic gloves
- leak-proof sealable bags or sample pots
- packaging for sending your sealable bags or sample pots to the laboratory
To take the dust swab sample:

1. Put on new disposable gloves - do not use hand sanitiser and make sure you do not contaminate them with disinfectant as it could affect your sample.

2. Open out the hand-held dust swabs. The total surface area of the swabs must be at least 900cm2.

3. Moisten the dust swabs using tap water or bottled still water (do not use sparkling water or water treated with antibacterial agents or acids). Moisten the swabs by putting them into a plastic bag and pouring water onto them inside the bag, then shaking.

4. Swab at least 20 different places around the house including ledges, partitions, ventilation baffle and anywhere else dust has settled. Do not take samples from feeding systems.

5. Make sure that both sides of the swabs are completely covered with dust.

6. Package the swabs carefully (do not dislodge dust) into a leak-proof sealable bag or pot to send to the laboratory.

How to collect hand-held faecal swabs

Only take hand-held faecal swabs if you cannot use boot swabs and have fewer than 100 birds in the house at the time of sampling.

You will need:
- at least 2 hand-held swabs - the total surface area of all the swabs you use must be at least 900cm2
- tap water or bottled still water for moistening swabs - do not use sparkling water or water treated with antibacterial agents or acids
- disposable plastic gloves
- leak-proof sealable bags or sample pots
- packaging for sending your sample bags or pots to the laboratory
To take a hand-held faecal swab:

1. Put on new plastic gloves — do not use hand sanitiser and make sure you do not contaminate them with disinfectant as it could affect your sample.

2. Open out the hand-held faecal swabs.

3. If not already moistened, moisten the fabric swabs with the tap water or bottled still water. Moisten the swabs by putting them into a grip-seal bag and pouring water onto them inside the bag, then shaking.

4. Thoroughly swab the pen area, the floor and any perches in several different areas where faeces have built up.

5. Make sure that both sides of the swab are completely covered in faeces.

6. Put the swabs carefully (so the collected faeces stays in place) into 2 sealable bags or pots to send to the laboratory.

What to do with the samples

Label the samples

On each label, you must include the flock identification. This is usually the flock’s house name or number, month and year the flock moved into the house.

On the label or the laboratory’s submission form or IT system, also provide the:
- type of sample taken
- date you took the sample
- registration number, County Parish Holding (CPH) number (in Great Britain), or DAERA flock number
- name and address of the flock’s premises
- age of the flock
- number of birds in the flock
- contact details of the person sending the sample
If you use a fabric bootswab as a hand swab, you must make sure that this is accurately labelled, so that the laboratory can correctly identify the sample type in its report.

Send samples to a NCP-approved laboratory

If your flock is in Great Britain, you must send your samples to a laboratory approved by APHA (https://www.gov.uk/government/publications/salmonella-in-poultry-testing-laboratories-in-the-uk) for testing.

If your flock is in Northern Ireland your samples must be sent to a laboratory approved by DAERA (https://www.daera-ni.gov.uk/articles/salmonella) for testing.

You should send your samples on the day you collect them, and they must be sent without undue delay. Legislation requires that they are sent within 24 hours of collection. If they are not sent promptly, they must be refrigerated. Refrigerate them at 2 to 8°C if you cannot send them on the day of collection and send them first thing on the next day by guaranteed same or next day delivery or courier. You must not freeze samples.

You can send biological samples in the post but make sure you use appropriate packaging. Refer to the Dispatch Methods for UN3373 Category B Samples (https://www.gov.uk/government/publications/packaging-and-transport-requirements-for-patient-samples-un3373) for further information (which is written in relation to posting human samples but applies equally to NCP samples).

Check that the laboratory can start testing your samples within 48 hours of receiving them and within 4 days of sampling. Some laboratories may not be able to process samples received late in the week or on weekends or public holidays.

You will need to send more samples if:
- your samples are delayed in the post
- you send an insufficient number of samples
- the weight of dust is under 100g or the swab area is too small (where relevant)
- the laboratory cannot start testing within 4 days
The laboratory sends the results to:
- the person who sent the sample, or the registered owner of the sampled flock
- the person who sent the sample, or the registered owner of the sampled flock
- APHA or DAERA if the sample tests positive for salmonella (this may be termed a Zoonoses Order or a ZO2 notification by some laboratories)
APHA or DAERA will also require your laboratory to send them the suspect salmonella bacteria they have identified for further testing.

This official testing cannot begin until the bacteria and required supporting information has been received from your laboratory. Once received, testing can take up to 12 working days for certain strains of salmonella so that they can be accurately identified. Accurate identification is important as only certain strains of salmonella need further NCP official action to be taken under the NCP.

You will be informed by APHA or DAERA of the final result as soon as it is available.

If your samples test positive for salmonella you’ll need to inform your vet of the positive result, if you have not made arrangements with the testing laboratory to do this automatically.

Official sampling at your premises

Officials may take a routine official sample in the lifetime of the flock. Each year officials must sample a single flock on 10% of broiler holdings with more than 5,000 birds. These flocks are selected at random. The same premises will not be selected again for at least 5 years.

In England, Scotland and Wales, routine official samples will be taken by an APHA official and in Northern Ireland, an official from DAERA will take routine official samples.

You will be charged for these visits. An official sample can replace an operator sample. See the official sampling fees for England, Scotland and Wales (https://www.gov.uk/salmonella-national-control-programmes-fees). Contact DAERA (https://www.daera-ni.gov.uk/) for details of fees in Northern Ireland.

Officials from APHA or DAERA will also visit to take samples:
- if Salmonella Enteritidis or Salmonella Typhimurium (including monophasic Salmonella Typhimurium) has been detected in another flock or in a previous crop of flocks on your premises
- from all the flocks on your premises if a positive test for Salmonella Enteritidis or Salmonella Typhimurium (including monophasic Salmonella Typhimurium) at the hatchery you use has been traced to one of your flocks
- from flocks where there is no evidence of testing
- in cases where the competent authority (Defra, DAERA, Scottish Government or Welsh Government depending on your location) considers it appropriate
If your sample tests positive for regulated types of salmonella

APHA or DAERA test bacteria from your sample supplied to them by your laboratory and review the positive results for regulated types of salmonella. If the positive result is not due to a vaccine type of salmonella, official restrictions may be applied to your flock and you must comply with their requirements.

Regulated salmonella in broiler chicken NCP are:
- Salmonella Enteritidis
- Salmonella Typhimurium (including monophasic Salmonella Typhimurium)
In Great Britain restrictions are usually only applied to a positive broiler flock if infection has persisted in the shed since a previous crop of positive birds.

Inform your vet of the positive result if you have not made arrangements with the testing laboratory for this to happen automatically.

When you send a flock to slaughter, you must include in the Food Chain Information (FCI) documents any positive salmonella result, whether for a regulated type or not.

This is a legal requirement and the birds may not be slaughtered if this information is not provided.

In exceptional circumstances, confirmatory sampling for a positive salmonella flock may be allowed where there is compelling evidence that the initial operator result may be a false-positive. In these cases in Great Britain, APHA will alert the relevant administration (known as the competent authority; Defra if your flock is in England, the Scottish Government if you are based in Scotland or the Welsh Government if your flock is in Wales).

This confirmatory official sampling is only permitted when there is cause to question the results of the original testing, for example when there is strong evidence that the original result was affected by contamination at the lab and so the original result may not reflect the salmonella status of your flock.

If, after considering the evidence that you or your vet have supplied, the competent authority agree that the initial result may be a possibly false positive, then either APHA or DAERA will advise you accordingly, and make arrangements to undertake official sampling.

If this type of confirmatory testing is carried out, a government official may ask you to cull 5 birds. They will take the carcases and store their organs when they collect confirmatory samples. They may use organs of these birds to test for the presence of antibiotics if the confirmatory test is negative.

Positive tests for Salmonella Enteritidis or Typhimurium

If Salmonella Enteritidis or Salmonella Typhimurium (including monophasic Salmonella Typhimurium) is identified, APHA or DAERA will take samples from every other flock on your premises, probably from your next crop of birds.

If you have a positive test result for these types of salmonella, you must arrange for the affected birds to be slaughtered either:
- by an abattoir prepared to accept them (as the meat will need to be heat treated and not all processors will have a market for this meat)
- on farm by a licensed slaughterer and then disposed of as animal by-products at an appropriately approved plant (by rendering or incineration)
You should also clean and disinfect the positive house.

APHA or DAERA will also take samples from all your other flocks (usually for broilers in your next crop of birds). If these tests are positive for Salmonella Enteritidis or Salmonella Typhimurium (including monophasic Salmonella Typhimurium), APHA or DAERA will place the positive house under a movement restriction.

This means that you must have a licence from APHA or DAERA to move equipment, animals or animal products on to, or off your premises. This includes sending the birds to slaughter. The restriction notice also means you will have to clean and disinfect the restricted poultry house under official supervision and get negative test results from official post disinfection samples once the restricted house is empty after the birds have been sent to slaughter or been culled.

Once you are under movement restrictions, you can only restock your restricted poultry house after tests come back negative.

A government veterinarian visit to your premises to give advice on salmonella control will be offered. Your private veterinarian will also be able to provide advice, and if you are in a farm assurance scheme or a member of an industry body they may also be able to assist.

You will not have to pay for any samples or testing carried out by APHA or DAERA because of a positive test result.

Keep records

You must keep records for specified times. Officials may check your records at any time.

Keep salmonella test records

Each time you take samples, you must record the:
- date you took the sample
- flock identification (this is the flock’s house name or number, and the month and year the flock moved into the house)
- type of sample (such as boot swabs or dust sample)
- age of the flock
- date you plan to have the flock slaughtered
- laboratory that tested the sample
- test result
These records must be kept for at least 2 years and be made available to officials on their request.

Keep movement records

You need to record any movement of birds to or from your premises. For each movement, record the:
- date of movement
- number of birds
- age of the birds
- house name or number, and the month and year the flock moved onto your premises
- address that the birds moved from (including the building name or number)
- address that the birds moved to (including the building name or number)
These records must be kept for at least 2 years and be made available to officials on their request.

Keep medication records

You must record various information about the medicines used to treat your birds. Officials auditing your NCP compliance will focus on the following aspects of your overall medicine records as these are relevant in assessing if medicines use may have compromised the likelihood of NCP testing identifying a salmonella positive flock:
- medicines used (specifically antibiotics and salmonella vaccinations)
- dose rate
- start and end date of treatment
- route of administration
- identification of the treated birds
- end date of the withdrawal period
You must keep your medicine records for at least 5 years and make them available to an official on their request. Find out more about record keeping requirements for veterinary medicines (https://www.gov.uk/guidance/record-keeping-requirements-for-veterinary-medicines).

Include test results in food chain information (FCI) documents for abattoirs

When you send some or all the birds in your flock or flocks to an abattoir for slaughter for human consumption you must fill in a FCI declaration document (https://www.food.gov.uk/business-guidance/food-chain-information).

In the FCI document, you must declare:
- the most recent NCP test result for the specific flock
- the date the sample was collected
- other diagnoses
- the use of medicines
If the most recent NCP test was a negative result, you must also declare any previous positive salmonella test results for that specific flock with the sample collection dates. This includes results not taken as part of the NCP programme.

You do not need to provide FCI if:
- you slaughter the birds on the farm and dispose of them as animal by-products
- you sell your birds direct to customers (either as live birds or following on site slaughter for human consumption)
If you sell directly (farm gate or other direct sales), you may be regarded as a food business and so must register with your local authority. This requirement applies to the sale of meat from your flock. If your flock tests positive for salmonella, they will advise you on what you need to do to protect the health of your customers.

You will need a slaughterer’s licence (https://www.gov.uk/guidance/get-a-certificate-of-competence-or-licence-to-slaughter-or-kill-animals) or to employ someone licenced to slaughter birds on your farm.

Selling your live birds direct to customers

If selling live birds, advise your customer about:
- any positive salmonella results
- recent usage of veterinary medicines for which the withdrawal time has not yet ended
Get advice

If you need more advice, contact APHA (https://www.gov.uk/government/organisations/animal-and-plant-health-agency/about/access-and-opening), DAERA (https://www.daera-ni.gov.uk/contact) or your vet.