Impact of single and mixed infections with Escherichia coli and Mycoplasma gallisepticum on Newcastle disease virus vaccine performance in broiler chickens: an in vivo perspective.

Autor: Awad NFS; Department of Avian and Rabbit Medicine, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt., Abd El-Hamid MI; Department of Microbiology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt., Hashem YM; Department of Mycoplasma Research, Animal Health Research Institute, Giza, Egypt., Erfan AM; National Laboratory for Veterinary Quality Control on Poultry Production, Animal Health Research Institute, Dokki, Giza, Egypt., Abdelrahman BA; Department of Pathology, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt., Mahmoud HI; Animal Wealth Development Department, Faculty of Veterinary Medicine, Zagazig University, Zagazig, Egypt.
Jazyk: angličtina
Zdroj: Journal of applied microbiology [J Appl Microbiol] 2019 Aug; Vol. 127 (2), pp. 396-405. Date of Electronic Publication: 2019 Jun 14.
DOI: 10.1111/jam.14303
Abstrakt: Aims: This study was designed to investigate, in an in vivo setting, the effects of single and combined infections with either Mycoplasma gallisepticum (MG) and/or Escherichia coli on the chicken immune response induced by Newcastle disease virus (NDV) vaccine.
Methods and Results: Humoral immunity was measured through detection of NDV antibody and anti-NDV IgG titres using haemagglutination-inhibition test and enzyme-linked immunosorbent assay, respectively. In addition, the expression levels of pro-inflammatory cytokines' genes (interleukin (IL) 6, IL4 and interferon (IFN) γ) were analysed using quantitative reverse transcription PCR. Significant (P < 0·05) results in all immunological parameters were detected in the vaccinated noninfected chicken group in comparison with those in groups exposed to bacterial infections. Bacterial infection along with vaccination hampered the NDV antibodies production and reduced the vaccine upregulated cytokine genes. The vaccinated mixed infection group reported lower antibody titres and cytokines expression levels compared to those in the single infection groups. All the previously enhanced immunological parameters reflected the maximum protection post challenge with velogenic viscerotropic NDV in the vaccinated noninfected chicken group.
Conclusions: These findings provide novel insights into the immunosuppression activities of MG and E. coli infection in chickens vaccinated against NDV.
Significance and Impact of the Study: This study hopes to provide a better insight to the immunosuppressive action of bacterial pathogens in chickens. This will help to improve biosecurity strategies during NDV vaccination in the future.
(© 2019 The Society for Applied Microbiology.)
Databáze: MEDLINE
Externí odkaz: