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Measures and Best Practice to Minimise Infection of Remaining Birds with Campylobacter When Broiler Flocks are Thinned

Silsoe Research Institute
ADAS Consulting Ltd
University of Bristol
Start date
End date
This research project will provide a general overview of current thinning practices on UK broiler farms and provide recommendations suitable for guidance on thinning procedures.
  • Risk assessment and suggested SOPs produced by advisory panel of researchers, consultants and industrial partners.
  • Discussions with and collection of information from major poultry companies, major retailers and poultry industry organisations responsible for auditing activities.
  • Collation of information and experience from European sources.
  • Visual auditing of company thinning procedures against advisory panel's risk assessment and SOPs together with sampling of flocks and thinning equipment for campylobacter in order to identify areas of risk.
  • Microbiological investigation to establish campylobacter status of flock pre and post thinning and identify possible sites of cross-contamination.
  • Engineering interventions including comparison of manual and machine catching.
  • Production of recommendations suitable for the production of guidance material for thinning procedures and suggestion of any suitable intervention measures.
More information
Thinning is the removal of a portion of the flock before depopulation. It is a common practice throughout the UK poultry industry, allowing farmers to maximise the use of space for rearing birds while meeting the necessary welfare requirements for stocking density and consumer demands for birds of different sizes. However, by its nature, thinning is a breach of biosecurity.

Background information from Food Standards Agency project 'Studies to identify critical control points for infection of live birds or contamination of poultry carcasses with campylobacter and salmonella species', DEFRA's project 'Epidemiological studies and development of practical control measures for campylobacter in broiler flocks' and data from international and UK companies have indicated that the thinning process introduces and/or exacerbates campylobacter infection of the remaining flock.

The project aims to collect advice on Code of Practices (COPs) and Standard Operating Procedures (SOPs) from major poultry companies, retailers and auditing organisations.

A visual audit of company thinning procedures will be compared against written protocols and testing of flocks and depopulation equipment for campylobacter in order to identify the areas of risk. The study will produce recommendations suitable for the production of guidance material and suggest any appropriate intervention measures.

Find more about this project and other FSA food safety-related projects at the Food Standards Agency Research webpage.

Funding Source
Food Standards Agency
Project number
Bacterial Pathogens
Meat, Poultry, Game