European Journal of Epidemiology

, Volume 8, Issue 6, pp 851–855

Epizootics of Salmonella infection in poultry may be the result of modern selective breeding practices

  • P. R. Hunter


This paper discussess the hypothesis that a major factor in the epizootics of Salmonella infection in poultry is a declining host genetic diversity. A computer model is described which is based on models that have been previously used to investigate host-pathogen coevolution in cereal crops. It is shown that, as host genetic diversity declines, parasite diversity also declines to a lower equilibrium level. With a highly diverse host, parasite numbers decline to zero. With a homogeneous host population, after an initial decline, there is a rapid increase in parasite numbers, due to the selection of a particularly well adapted parasite strain. This simple computer simulation is used as the basis for a discussion of the literature supporting the suggestion that a major factor in the epizootic of Salmonella in poultry is related to the low genetic diversity of commercial poultry flocks.

Key words

Salmonella Co-evolution Poultry Computer modelling Sex 


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Copyright information

© Gustav Fischer 1992

Authors and Affiliations

  • P. R. Hunter
    • 1
  1. 1.Public Health LaboratoryCountess of Chester HospitalChesterUK

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