Managing the Challenges to the Egg Industry Posed by New SE PTs

<OL type="I"> <LI> Keeping the egg industry involved and informed

<OL> <LI> Formation of an industry liaison group -
To monitor progress and to keep stakeholders informed.
<LI> Production of reports and advice for the UK egg industry and dissemination of information by the production of papers for peer-reviewed and trade publications and seminars with the UK egg industry and related bodies -
To ensure, with objective 1, that industry gains maximum benefit from the research.
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<LI>Ensuring that the work is relevant scientifically and to the egg industry

<OL> <LI>Assembling a library of Salmonella isolates -
To ensure that an appropriate range of ‘new’ SE PTs and other potentially egg-associated serovars are included in the proposed studies.
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<LI>Determining the risk to the current vaccination strategy

<OL> <LI> Laboratory studies on Salmonella-serum interactions -
To identify PTs, which differ most from PT4 in their interaction with components of the immune system so that animal studies can be minimised.
<LI>Challenge of PT4-vaccinated and non-vaccinated hens with SE PTs -
To determine the protective effects of current vaccines against new PTs and their tissue distribution.
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<LI>Examining the risks that ‘new’ PTs pose to shelf life, from farm to consumer

<OL> <LI> Examination of survival of Salmonella isolates in egg albumen at 20 and 42ºC -
To provide, with objectives 5, 8 and 9, an explanation of high egg contamination rates seen in some recent outbreak investigations.
<LI> Examination of lysozyme binding to Salmonella isolates -
To examine the hypothesis that lysozyme in albumen binds less well to ‘new’ SE PTs allowing improved survival in egg contents.
<LI> Examination of the growth of Salmonella isolates in whole eggs -
To examine the hypothesis that the outbreak-related PTs grow more rapidly in fresh eggs.
<LI>Examination of SE isolates for the presence of the plasmid that allows rapid growth -
To examine the hypothesis that outbreak-related PTs contain a novel plasmid, which increases contamination levels in egg contents.
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<LI>Improving surveillance and current vaccines

<OL> <LI> Determination of LPS structures in SE PTs -
To identify key differences between SE PTs and selected other serovars that relate to behaviour in hens and egg contents.
<LI> Supplying isolates/genetic material to VLA collaborators for genomic indexing and challenge studies -
To identify genetic mechanisms by which ‘new’ PTs differ from PT4 in hens and egg contents so that potential new vaccine components can be identified and surveillance improved. To select isolates for use in egg and environmental challenge studies.