Comparative evaluation of outer membrane protein and whole cell antigen vaccine against avian pathogen Escherichia coli infection in broiler chicken

Basharat Maqbool Wani; Shayaib Ahmad Kamil; Showkat Ahmad Shah; Masood Saleem Mir; Mir Nadeem Hassan; Zahid Amin Kashoo; Mudasir Ali Rather; Majid Shafi; Zahoor Ahmad Wani; Nadeem Shabir; Nazli Tizro; Akeel Bashir; Atif Khurshid Wani

doi:10.18502/ijm.v18i1.20935

Basharat Maqbool Wani Department of Veterinary Pathology, FVSc & AH, Shuhama, SKUAST-Kashmir, India
Shayaib Ahmad Kamil Department of Veterinary Pathology, FVSc & AH, Shuhama, SKUAST-Kashmir, India
Showkat Ahmad Shah Department of Veterinary Pathology, FVSc & AH, Shuhama, SKUAST-Kashmir, India
Masood Saleem Mir Department of Veterinary Pathology, FVSc & AH, Shuhama, SKUAST-Kashmir, India
Mir Nadeem Hassan Depatment of Veterinary Microbiology & Immunology, FVSc & AH, Shuhama, SKUAST-Kashmir, India
Zahid Amin Kashoo Depatment of Veterinary Microbiology & Immunology, FVSc & AH, Shuhama, SKUAST-Kashmir, India
Mudasir Ali Rather Department of Veterinary Public Health, FVSc & AH, Shuhama, SKUAST-Kashmir, India
Majid Shafi Department of Veterinary Pathology, FVSc & AH, Shuhama, SKUAST-Kashmir, India
Zahoor Ahmad Wani Department of Veterinary Parasitology, FVSc & AH, Shuhama, SKUAST-Kashmir, India
Nadeem Shabir Department of Animal Biotechnology, FVSc & AH, Shuhama, SKUAST-Kashmir, India
Nazli Tizro Department of the Environment, College of Natural Resources and Environment, Science and Research Branch, Islamic Azad University, Tehran, Iran
Akeel Bashir Department of Veterinary Pathology, FVSc & AH, Shuhama, SKUAST-Kashmir, India
Atif Khurshid Wani Department of Veterinary Biochemistry, FVSc & AH, Shuhama, SKUAST-Kashmir, India

DOI: https://doi.org/10.18502/ijm.v18i1.20935

Keywords: Escherichia coli; Colibacillosis; Chickens; Bacterial outer membrane proteins; Vaccines; Immune response

Abstract

Background and Objectives: Present study was aimed at assessing protective efficacy of outer membrane protein (OMP) vaccine in comparison to inactivated whole cell antigen vaccine after challenge with homologous serogroup (O2) of avian pathogenic Escherichia coli in broiler chickens.

Materials and Methods: The outer membrane proteins were extracted by sarcosyl method and protein concentration was determined by nanodrop spectrophotometer. The study comprised of 120 birds divided into 6 groups. The birds were subcu- taneously immunized twice with primary vaccine in the first week followed by booster vaccine in second week.

Results: The protection rate of 82% was found in whole cell inactivated antigen, 91% in OMP vaccine and 27% among the unvaccinated group. The antibody (IgG) response was found significantly higher in OMP vaccine group than whole cell antigen group. In unvaccinated groups chicks, the antibody titer never reached to the protective level till the termination of experiment. The bacteria were re-isolated from the infected broiler chickens for the confirmation of induced infection and were characterized using standard cultural and biochemical tests belonging to O2 serogroup.

Conclusion: Our study demonstrated that the outer membrane protein (OMP) vaccine provided significantly higher protec- tion (91%) and antibody response compared to the inactivated whole cell antigen vaccine (82%) against Escherichia coli O2 infection in broiler chickens. Birds vaccinated with OMP exhibited fewer pathological lesions and a stronger immune response. The findings underscore the potential of OMP-based vaccines as a safer, more immunogenic alternative for con- trolling colibacillosis.