Characterization of infectious laryngotracheitis virus isolated from commercial layer chickens in Bangladesh during the year 2021–2022

Authors

  • Md Mostofa Kamal Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh, Bangladesh
  • Mohammad Sadekuzzaman Central Disease Investigation Laboratory, Department of Livestock Services, Dhaka, Bangladesh
  • Kohinoor Parvin Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh, Bangladesh
  • Md Enamul Haque Department of Microbiology, Sheikh Hasina University of Science and Technology, Bhairab, Bangladesh
  • Sajedul Hayat Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh, Bangladesh
  • Md Ariful Islam Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh, Bangladesh
  • Mst Minara Khatun Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh, Bangladesh
  • Mahbubul Pratik Siddique Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh, Bangladesh
  • Sham Soun Nahar Livestock Research Institute, Mohakhali, Dhaka, Bangladesh
  • A K M Khasruzzaman Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh, Bangladesh
  • Muhammud Tofazzal Hossain Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh, Bangladesh
  • Md Alimul Islam Department of Microbiology and Hygiene, Bangladesh Agricultural University, Mymensingh, Bangladesh

Keywords:

Layer chickens; PCR; AGIDT; VNT; Mice; ITPI

Abstract

Objective: Infectious laryngotracheitis virus (ILTV) is responsible for causing infectious laryngo­tracheitis (ILT), which is a rapidly spreading and extremely transmissible disease in chickens. The current research aims to isolate and characterize ILTV from layer chickens in Bangladesh.

Materials and Methods: A total of 345 samples (trachea, larynx, and lungs) were collected from ILT-suspected dead and sick layer chickens of 32 ILT-suspected farms in three different outbreak districts (Gazipur, Tangail, and Mymensingh) of Bangladesh during the outbreak year 2021-2022. Rapid detection kits examined the samples for avian influenza virus (AIV) and Newcastle disease virus (NDV). ILTV-specific primers were used to screen 72 NDV- and AIV-negative samples by poly­merase chain reaction (PCR). Using chorioallantoic membrane (CAM), the study isolated the ILT virus from 9 to 10-day-old seronegative embryonated chicken eggs (ECEs) using selected PCR-positive samples. The virus was confirmed using nucleotide sequencing, agar gel immunodiffusion test (AGIDT), viral neutralization test (VNT), and pathogenicity evaluations using mortality index for chicken embryos (MICEs) and intra-tracheal pathogenicity index (ITPI).

Results: The results indicated that among the PCR-positive 10 samples, only two (Alim_ILT_1001 and Alim_ILT_1,000) were found positive using ECEs. There were two field isolates of ILTVs, as shown by the amplicon size of the ICP4 gene-based PCR. A phylogenetic study of the ICP4 gene revealed that the recent isolates have a close similarity with the ILTV isolates of Turkey, Bangladesh, and Australia. AGIDT revealed strong precipitation lines due to ILTV-specific antibod­ies reacting with field viruses, while VNT neutralized both isolates with conventional ILTV antibod­ies. The pathogenicity testing indicated that Alim_ILT_1001 had MICE and ITPI values of 0.77 and 0.63, whereas Alim_ILT_1,000 had 0.71 and 0.57.

Conclusion: Both the ILTV isolates have similarities with the isolates of Turkey, Bangladesh, and Australia, and they are highly virulent for chickens.

Adv. Vet. Anim. Res., 11(2): 398-407, June 2024

http://doi.org/10.5455/javar.2024.k789

Downloads

Download data is not yet available.
Abstract
33
PDF
31

Downloads

Published

2024-08-29

How to Cite

Kamal, M. M., Sadekuzzaman, M., Parvin, K., Haque, M. E., Hayat, S., Islam, M. A., Khatun, M. M., Siddique, M. P., Nahar, S. S., Khasruzzaman, A. K. M., Hossain, M. T., & Islam, M. A. (2024). Characterization of infectious laryngotracheitis virus isolated from commercial layer chickens in Bangladesh during the year 2021–2022. Journal of Advanced Veterinary and Animal Research, 11(2), 398–407. Retrieved from https://banglajol.info/index.php/JAVAR/article/view/75720

Issue

Section

Original Articles