Review of the Food-borne Zoonoses Research ... - ARCHIVE: Defra

Project code: OZ0327
Project title: Effect of immunosuppression associated with pointof-lay
on Salmonella infection and immunity in laying
hens
Start date (dd/mm/yy): 01/07/06
End date (dd/mm/yy): 20/06/09
£198,000 (Defra: £37205; BBSRC: £160795)
Total cost:
Affiliation: Department of Veterinary Pathology,
University of Liverpool
Abstract of research
Previously we have shown that suppression of cell-mediated immunity at point-of-lay in
hens is a critical factor in reproductive tract infection by Salmonella enterica and
subsequent transmission to eggs. This project will characterise the immunolgical
structure of the avian reproductive tract, which immunological changes take place at
point-of-lay and determine whether these affect the immune response to Salmonella and
in particular whether suppression of immune responses reduce the efficacy of
vaccination, leading to a gap in immune protection. This will be achieved through
investigating changes in cell populations, expression of key cytokines and chemokines
and antibody levels. We will assess changes in protection through in vivo challenge
experiments. We will then look at how changes in vaccination or stimulation of the
immune system through recombinant cytokines can improve protection and prevent any
gap in immunity.
Review summary
Research on the avian immunological response during the point-of-lay period, when
salmonella breakdowns tend to occur, should provide valuable information for salmonella
control. The overall plan for the work is clearly laid out and the researchers are making
good progress towards the stated objectives.
If this approach proves to be successful, there will be a need to understand how the
information can be utilised in the field and possible to investigate changes at the end-oflay
when salmonella breakdowns are also known to occur.
It is appropriate that this work is jointly funded with BBSRC as it may take some years for
results of the work to benefit UK poultry industry.
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