Skip to main content
ARS Home » Southeast Area » Athens, Georgia » U.S. National Poultry Research Center » Endemic Poultry Viral Diseases Research » Research » Publications at this Location » Publication #421171
Research Project: Systems Biology Approaches to Develop Medical Countermeasures to Detect, Prevent, and Control Poultry Production Viral Diseases

Location: Endemic Poultry Viral Diseases Research

Title: Contribution of the Major Histocompatibility Complex (MHC) B haplotype on host resistance to multiple strains of infectious bursal disease virus

Author
item Blakey, Julia
item GARCIA, MARICARMEN - University Of Georgia
item JACKWOOD, DARAL - The Ohio State University
item DALLOUL, RAMI - University Of Georgia
item Mohanty, Sujit
item Dunn, John

Submitted to: Avian Pathology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/17/2025
Publication Date: N/A
Citation: N/A

Interpretive Summary: Infectious bursal disease (IBD) is a highly contagious disease of young chickens which causes lasting damage to the hosts immune system. Despite being first described over 60 years ago, IBD is still a major cause of disease in the commercial poultry industry. IBD is caused by infectious bursal disease virus (IBDV), which is highly resistant in the environment. Strategies to control IBDV have mainly focused on vaccination, however IBD continues to be a significant concern. Resistance to certain diseases may be passed from parent to offspring (genetic resistance) and can be utilized as a method of disease control. To establish if genetic resistance to IBDV exists in chickens, we evaluated the susceptibility of nine inbred chicken lines to three different strains of IBDV. The results showed differences in disease susceptibility were dependent on both the inbred chicken line as well as the strain of IBDV. The overall data suggest that genetic resistance to IBDV does exist depending upon the challenge strain of virus. Further research into the mechanisms of resistance is required and will provide valuable knowledge that can be applied to current IBD control programs.

Technical Abstract: Seven lines of major histocompatibility complex (MHC)-B congenic specific pathogen free (SPF) chickens and two lines of SPF chickens with the same B haplotype but differing non-MHC genes were utilized to investigate the effect of MHC-B haplotype on infectious bursal disease (IBD) development. In initial experiments, chickens were challenged at 28 days of age with the variant infectious bursal disease virus (IBDV) strain AL-2, classical IBDV strain STC, or very virulent (vv) IBDV strain rA. IBD severity was evaluated throughout the seven-day course of infection by assessing survivability and histopathological analysis of bursal lesion scores. Follow up studies investigated the effects of varying STC challenge doses on IBD development. Results demonstrated that the challenge strain of IBDV has a large impact on MHC-B based genetic resistance. The most significant differences in survivability and bursal lesions were noted after challenge with the vvIBDV strain, with MHC-B congenic chicken lines B*13 and B*19 being the most susceptible. Based on survivability, the B*19 chicken line was also characterized as the most susceptible after challenge with high doses (105 EID50) of the STC strain, while lower doses (102 EID50 – 104 EID50) of the STC strain yielded inconsistent IBD induction amongst the chicken lines. No differences in survivability were detected among the inbred chicken lines when challenged with the variant strain AL-2. MHC-based genetic resistance to IBDV is mainly associated with survival during the early stages of infection and has minimal association with bursal damage and bursal lymphocyte depletion post-challenge in B congenic SPF chickens.