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The effect of hypovitaminosis A on the pathogenesis of Pasteurella multocida in turkeys

P P Aye1, T Y Morishita, Y M Saif

  • 1Department of Veterinary Preventive Medicine, The Ohio State University, Columbus 43210, USA.

Avian Diseases
|February 24, 2001
PubMed

Insights

Vitamin A deficiency in turkeys did not alter Pasteurella multocida`s invasion time but increased mortality, suggesting immune system impairment plays a key role in disease severity.

Area of Science:

  • Veterinary Pathology
  • Microbiology
  • Immunology

Background:

  • Pasteurella multocida invades host tissues via mucous membranes.
  • Vitamin A (VitA) deficiency is linked to mucous membrane damage, potentially affecting pathogen invasion.
  • Early pathogenesis of P. multocida in turkeys with and without VitA deficiency requires investigation.

Purpose of the Study:

  • To investigate the early stages of Pasteurella multocida pathogenesis in Vitamin A-deficient turkeys compared to healthy controls.
  • To determine the portal of entry, invasion dynamics, and tissue localization of P. multocida.

Main Methods:

  • Fifteen-week-old turkeys, both VitA-deficient and healthy, were inoculated with virulent P. multocida P-1059.
  • Microbial and histological examinations of the trachea, liver, lung, and internal organs were performed.
  • P. multocida reisolation and tissue invasion timelines were assessed post-inoculation.

Main Results:

  • Higher mortality rates were observed in VitA-deficient turkeys.
  • P. multocida was consistently reisolated from the trachea first, followed by the liver, blood, and lung in both groups.
  • Tissue invasion by P. multocida occurred within 3 to 24 hours post-inoculation in all turkeys.

Conclusions:

  • Altered mucous membrane integrity in VitA-deficient turkeys did not affect the systemic spread timeline of P. multocida.
  • Increased mortality in VitA-deficient turkeys is likely linked to impaired immune system function rather than delayed pathogen invasion.

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