Salmonella: get your breeding chickens tested
Find out when and how to take samples for testing, and what happens if one of your flocks tests positive.
You must take samples and send them to a laboratory for testing if you have a flock of 250 or more breeding birds. This is part of the national control programme (NCP) for salmonella, which aims to control salmonella in poultry flocks across the EU.
You must sample each of your flocks. A flock is a group of birds that shares the same air space, eg a chicken house or range.
If you’re not sure if your birds are considered to be in one or more flock, you can ask for advice from the Animal and Plant Health Agency (APHA) in England, Scotland or Wales, or the Department of Agriculture and Rural Development (DARD) in Northern Ireland.
When you don’t have to test a flock
You don’t have to have your flock tested if you only produce hatching eggs or day-old chicks for scientific or research purposes.
Register your flocks and hatchery before you get them tested
You must register each premises where you keep your flocks on one of the following:
- the Great Britain Poultry Register if you’re in England, Scotland or Wales
- the Northern Ireland Poultry Register if you farm in Northern Ireland
You must register your hatchery if it can incubate 1,000 or more eggs.
When you must not sample
Avoid taking samples during or shortly after giving antimicrobials (antibiotics) that affect salmonella. APHA or DARD could declare your flock positive for salmonella if:
- inspectors find from the flock medicine book that you’ve given antimicrobials
- the laboratory tests find antimicrobials in samples taken by inspectors
Contact one of the following for guidance on when to test after giving antimicrobials:
- the vet who prescribed the antimicrobials
- APHA if you farm in England, Scotland or Wales
- DARD if you farm in Northern Ireland
Paying for sampling equipment and tests
You need to buy your own sampling equipment. Contact one of the following to find out where:
- your vet
- the government-approved laboratory you plan to send samples to
- your nearest APHA office
You’ll also have to pay the laboratory charges for salmonella testing for your own samples and for annual APHA or DARD samples. Contact DARD for details of fees in Northern Ireland.
Official sampling at your premises
Officials will visit your premises to take official samples.
In Northern Ireland, DARD will take the official samples. In England, Scotland or Wales the official will be from APHA (possibly your vet if authorised to take official samples on behalf of APHA).
When to take samples
When you need to take samples 3 times a year
If Salmonella Enteritidis, Salmonella Typhimurium or monophasic strains of Typhimurium have been detected on your holding in the last year, you need to take samples:
- within 4 weeks of a flock moving to the laying unit or house
- in the middle of lay
- within the last 8 weeks of egg production
When you need to take samples twice a year
If no Salmonella enteritidis, Salmonella typhimurium or monophasic strains of typhimurium have been detected on your holding in the last year, you only need to take these samples near the beginning of lay and near the end of lay.
Take samples from your rearing flock
You must take samples at all of the following times:
- on the day the chicks arrive from a hatchery
- when they are 4 weeks old
- 2 weeks before you move them to the laying unit
Samples to send on the day of arrival
Send the following for laboratory testing on the day of arrival:
- the liners from boxes used to deliver the chicks - one box for every 500 chicks from each delivery, up to 10 boxes
- any chicks that are dead on arrival or that you cull within 24 hours of arrival, up to 60 carcasses from each hatchery
Samples to send when the chicks are older
Take samples using one of the following methods when the chicks are 4 weeks old, and again 2 weeks before you move them to the laying unit:
- 2 pairs of boot swabs for floor-reared birds
- 25 grams of a composite faeces sample for cage-reared or floor-reared birds (composite means the faeces are from many birds in the flock)
Take composite faeces samples from your rearing flocks
Use the following method to take a composite faeces sample from a rearing flock:
- Take several 1g samples from sites selected to represent the whole building, for cage-reared hens, or from all the buildings floor-reared hens go into, using a spatula or your hand inside a plastic glove or a plastic bag.
- Mix the 1g samples together to make a composite sample.
- Take 25g from the composite sample to send to the laboratory.
Use this table to find out the minimum number of 1g samples you need to take.
|Number of birds kept in building||Minimum number of faeces samples|
|1 to 24||A number equal to the total number of birds up to a maximum of 20 birds.|
|25 to 29||20|
|30 to 39||25|
|40 to 49||30|
|50 to 59||35|
|60 to 89||40|
|90 to 199||50|
|200 to 499||55|
Take samples from adult breeding flocks
Sample your adult breeding flocks every 3 weeks during the laying period, unless there’s been a positive test result for salmonella on your holding in the past 12 months.
You can take any of the following as samples from your flock:
- 5 pairs of boot swabs
- one pair of boot swabs and one dust sample
- 2 composite faeces samples of 150g each
Prepare to take samples
Take samples in the existing bedding - don’t put new bedding down.
Gather all the equipment you’ll need before you go into the laying house to prevent contamination. Take care to avoid contamination if you keep other animals (especially pigs or cattle) on your premises.
To prevent disinfectant or sanitiser affecting your sample, you:
- shouldn’t use hand sanitiser on your plastic gloves
- should put on your plastic overboots after you’ve walked through disinfectant
If you do wear plastic overboots when you walk through disinfectant, you should put on a another pair afterwards to protect the boot swabs from the disinfectant.
Take boot swab samples
You should use:
- disposable plastic overboots
- 2 pairs of boot swabs
- tap water or bottled still water for moistening boot swabs - never use sparkling water or water treated on the farm with antibacterial agents or acids
- disposable plastic gloves
- sealable bags or sample pots
- packaging for sending your sample bags or pots to the laboratory
Take 5 pairs of boot swabs from each flock. Moisten the boot swabs with water before you take samples.
Divide the house into 5 equal parts for sampling, and use one pair of boot swabs in each part. Take at least 100 steps with each pair of boot swabs, walking round the entire house. Drag your feet on the floor to pick up as much material as possible. If the house is divided into several pens, spend more time in the larger pens and less in the smaller pens.
When you’ve finished sampling, take the boot swabs off and turn them inside out carefully so that the faeces you’ve collected stays on them. Put 2 pairs of boot swabs together in one package and 3 pairs together in another package to send to the laboratory.
Take dust samples
Choose from one of these ways of taking a dust sample:
- collect 100g of dust from multiple places in the house and put it in a pot
- use one or more moistened fabric swabs with a total surface area of at least 900sq cms, put on new disposable gloves, and coat both sides of the swabs with dust collected from multiple places in the house
Avoid collecting dust from feeding systems.
You must package dust swabs separately from boot swabs.
Take composite faeces samples from caged flocks
If you’ve installed dropping belts or scrapers in your cages:
- run the belts or scrapers on the day you collect samples, to make sure that you pick up fresh faeces
- take faeces from every row or tier of the cage
- take faeces from the build-up on scrapers and at the end of belts
If you have a step-cage system without belts and scrapers, collect faeces from throughout the deep pit.
Collect the samples using a spatula or your hand inside a plastic glove or a plastic bag. Send 2 samples of at least 150g each to the laboratory.
You must label each sample submission form with a label that includes:
- the date you took the sample
- your registration number or your County Parish Holding (CPH) number or DARD flock number
- the identification of the flock - house name or number and the month and year you moved the flock into that house
- the name and address of the flock’s holding
- the age of the flock
- the number of birds in the flock
- the contact details of the person sending the sample
Send samples to a laboratory
You should send your samples on the day you collect them. Refrigerate them at 4°C if you can’t send your samples on that same day. You must not freeze samples.
Make sure the testing laboratory begins testing your samples within 4 days of when you collected them, otherwise you’ll have to take new samples.
You must send your salmonella NCP samples to a UK approved laboratory. Find laboratories approved by:
- DARD in Northern Ireland
- the Department for Environment, Food and Rural Affairs (Defra) in England and Wales
- the Scottish government
Tell APHA or DARD before moving birds to the laying unit
You need to contact APHA or DARD at least 2 weeks before you move birds to the laying unit and provide the dates on which:
- you’ll be moving the flock to the laying unit
- you think the flock is likely to stop laying
Get your test results
The laboratory usually sends the results to:
- the person who sent the sample
- the person the sampled flock is registered to
- APHA or DARD if the sample tests positive for salmonella
If your samples test positive for salmonella
APHA or DARD can send an officer to take samples if the laboratory finds that one of your flocks has tested positive for:
- Salmonella enteritidis
- Salmonella typhimurium (including monophasic Salmonella typhimurium)
- Salmonella hadar
- Salmonella infantis
- Salmonella virchow
APHA or DARD can also take 5 carcasses and store their organs. They may be tested for antimicrobials if the official control samples are negative.
If the official samples confirm Salmonella enteritidis or Salmonella typhimurium (including monophasic Salmonella typhimurium) you’ll have to:
- keep the flock that tested positive and its eggs on the farm
- make sure that the entire flock is slaughtered as soon as possible
- make sure that all eggs put in the hatchery since the time the flock was found to be infected are destroyed
APHA or DARD may check your hatchery to see if salmonella has become resident. In Northern Ireland DARD will check back in 6 weeks.
- increase your biosecurity measures to prevent the spread of salmonella
- thoroughly clean and disinfect the affected house
- take samples after the thorough cleaning and disinfection
You can only move new birds into the house if the results of the tests on the post-cleaning samples are negative.
If the sample confirms the presence of Salmonella hadar, Salmonella infantis or Salmonella virchow, you will have to make a plan with your vet and APHA or DARD to reduce or eliminate salmonella from the flock.
A government vet will also arrange to visit you and give you advice on salmonella control.
APHA or DARD will collect official samples from all your other flocks to check if they have salmonella.
If your birds are culled, Defra will automatically compensate you.
Keep records for at least 2 years. APHA or DARD officials can check your records at any time, eg during a routine NCP visit or a visit after a positive test result.
Keep test records
For each test you must record the:
- date you took the sample
- the flock identification, which is the flock’s house name or number, and the month and year the flock moved into the house
- type of sample, eg boot swab or dust sample
- age of the flock
- date you plan to have the flock slaughtered
- laboratory that tested the sample
- test result
Keep movement records
You need to record any movement of birds to or from your holding. 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 holding
- address that the birds moved from (including the building name or number)
- address that the birds moved to (including the building name or number)
Food chain information documents
You must declare the flock’s most recent salmonella test result in the food chain information (FCI) documents that you send with the birds to slaughter if you market any meat from your birds as fresh meat.
You don’t have to declare the most recent salmonella test if you heat treat all the meat from the flock before marketing it for human consumption.
Declare salmonella test results
You must declare all the NCP Salmonella test results, negative or positive, as well as the date the sample was taken from the flock in the Food Chain Information (FCI) documents accompanying the batch to slaughter.
This is a legal requirement and the birds may not be slaughtered if this information is not provided.
You can also read the code of practice for prevention of salmonella in breeding flocks (PDF, 63.4KB, 26 pages) , which provides best practice for preventing salmonella.