Layers - Salmonella Testing under the National Control Programme

All flocks on premises with more than 350 laying hens which are not accredited to any assurance scheme must comply with the National Control Programme for Salmonella in Laying Flocks. This programme was implemented in the UK on the 1st February 2008, which required that from the 1st January 2009, eggs originating from flocks infected with Salmonella Enteritidis or Salmonella Typhimurium cannot be sent for human consumption unless treated in a manner which will guarantee the elimination of Salmonella.

Does the National Control Plan (NCP) apply to all laying flocks?

The requirements of the NCP apply to all operators producing eggs on a commercial basis with the following two exceptions:

  1. All production is for private domestic use
  2. The holding has fewer than 350 hens and supplies direct to the consumer or via local retailers

Under this programme you are required to take the following samples:


  • One Chick delivery box liner (or hatchery tray liner taken at the hatchery) for every 500 chicks delivered. Up to a maximum of 10 for every batch delivered
  • Carcasses of all dead on arrivals chicks (to a maximum of 60) from each hatchery delivery.

Pullet Rearing

  • 2 pairs of boot swabs or one large composite faeces sample (for cage rearing) 2 week before moving to the layer house/ unit.

During Lay

  • 2 pairs boot swabs (barn or free range) or 2 x 150g composite faeces sample (cage reared) taken between 22-26 weeks of age THEN repeated every 15 weeks during production

For more information please contact a member of St Davids Poultry Team.


The NCP defines a flock as a single group or multiple groups of hens which share the same production unit (i.e. using the same air-space or range area).
Where housing systems are not typical, the situation is likely to be assessed on a case by case basis.
Multiple groups of hens which have ‘beak to beak’ contact (inside or outside the house) are likely to be treated as a single flock for the same epidemiological reasons, which would mean all those hens and all their eggs would be subject to the same official controls in the event of a positive result.


Defra - National Control Programmes for the reduction of Salmonella (External link)