Haematological and histological findings in Leghorn chickens infected with infectious bursal disease virus strain 73688

In the present study, specific-pathogen-free, 2-week-old Leghorn chickens were experimentally infected with strain 73688 of infectious bursal disease virus (IBDV) in order to evaluate haematological and histological changes that might suggest a pathomechanism for haemorrhages in this disease. At 96 hours post infection (hpi) a significant increase in prothrombin time was detected in the absence of visible lesions in myeloid bone marrow tissue and of significant thrombocytopenia. The aforementioned findings suggest alteration of the secondary coagulation mechanisms and not a direct effect of virus on thrombocytes or its precursors.