Immunosuppressive effects of Marek's disease virus (MDV) and herpesvirus of turkeys (HVT) in broiler chickens and the protective effect of HVT vaccination against MDV challenge

@article{Islam2002ImmunosuppressiveEO,
  title={Immunosuppressive effects of Marek's disease virus (MDV) and herpesvirus of turkeys (HVT) in broiler chickens and the protective effect of HVT vaccination against MDV challenge},
  author={Afm Fakhrul Islam and C. W. Wong and Stephen W. Walkden-Brown and Ian G. Colditz and K. Edla Arzey and Peter J. Groves},
  journal={Avian Pathology},
  year={2002},
  volume={31},
  pages={449 - 461}
}
Much of the impact of Marek's disease in broiler chickens is considered to be due to immunosuppression induced by Marek's disease virus (MDV). The present study evaluates the effects of an Australian isolate of pathogenic MDV (strain MPF 57) and a non-pathogenic vaccinal strain of herpesvirus of turkeys (HVT) (strain FC 126) on the immune system of commercial broiler chickens for 35 days following challenge at days 0 or 3 of age. It also investigates the extent of protection provided by HVT… Expand
Pathotyping of Australian isolates of Marek's disease virus in commercial broiler chickens vaccinated with herpesvirus of turkeys (HVT) or bivalent (HVT/SB1) vaccine and association with viral load in the spleen and feather dander.
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Early infection with Marek’s disease virus can jeopardize protection conferred by laryngotracheitis vaccines: a method to study MDV-induced immunosuppression
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Highly virulent Marek’s disease virus strains affect T lymphocyte function and viability of splenocytes in commercial meat-type chickens
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It is demonstrated that currently used vaccine protocols confer high levels of protection against MDV-induced tumors (protection index=100), but do not protect against late-MDV-IS; thus, commercial poultry flocks could suffer late- MDv-IS even in complete absence of tumors. Expand
The effects of in ovo administration of encapsulated Toll-like receptor 21 ligand as an adjuvant with Marek’s disease vaccine
TLDR
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TLDR
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Differential attenuation of Marek's disease virus-induced tumours and late-Marek's disease virus-induced immunosuppression.
TLDR
It is suggested that the immunosuppressive ability of MDV might follow a continuous spectrum and only the most virulent MDVs can overcome a certain threshold level and induce clinical MDV-IS in the ILT model. Expand
Influence of Marek's disease virus vaccines on chicken melanoma differentiation-associated gene 5-dependent-type I interferon signal transduction pathway with a highlight on their secondary impact on the immune responses post Newcastle disease virus vaccination.
TLDR
Interestingly, increasing the doses of the two vaccines led to dose-dependent down-regulation in the expression pattern of the investigated pathway, five and ten days post vaccination, which was lower in case of Rispens and HVT-VP2 vaccines. Expand
Deletion of the meq gene significantly decreases immunosuppression in chickens caused by pathogenic marek's disease virus
TLDR
Findings suggested that the Meq gene played an important role not only in tumor formation but also in inducing immunosuppressive effects in MDV-infected chickens. Expand
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