Application of qRT-PCR for improved understanding and control of infectious bursal disease in chickens

Abstract

The advent of real time polymerase chain reaction test (qPCR) allows greater diagnostic and research capacity especially beneficial in the field of virology. Infectious bursal disease (IBD) is a well-known viral disease of poultry and occurs world-wide despite widespread use of vaccination. In this thesis study, the real time reverse transcription method (qRT-PCR) was used to address to a range of research questions to provide better understanding and control of IBD in chickens in Australia and world-wide. One experiment was conducted to define the differences between Australian endemic classical and variant infectious bursal disease virus (IBDV) strains by infecting maternal antibody (MAb) free specific pathogen free (SPF) chickens separately with classical strain 06/95 and variant strain 02/95 in isolators. The results revealed that the two IBDV strains did not differ in the degree of bursal atrophy induced, IBDV viral RNA (vRNA) load in bursal and non-bursal lymphoid organs and faecal shedding but variant strain 02/95 induced a greater antibody response to the infection than classical strain 06/95 which was associated with a more rapid decline in IBDV vRNA genome copy number (VCN) in lymphoid organs.