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Infectious bursal disease virus (IBDV) is the causative agent of one of the most important viral diseases affecting the poultry industry worldwide. The virus causes an acute, highly contagious and immunosuppressive disease in chickens. Previous studies have demonstrated that in addition to B cells, macrophages can support the replication of IBDV. Since mesenchymal stem cells in bone marrow regulate the differentiation and proliferation of hematopoietic precursors, the interaction between IBDV and mesenchymal stem cells was investigated. Mesenchymal stem cells were isolated from chicken bone marrow. The classical IM strain and the variant strain-E of IBDV, both adapted to grow in a chicken macrophage cell line, were used to infect mesenchymal stem cells. Primary chicken mesenchymal stem cells were highly susceptible to replication of IBDV. Both viruses induced cytopathic effects and replicated to high titers in mesenchymal stem cells. The finding that IBDV can replicate in mesenchymal stem cells provides new information on the susceptible target cell population within the host and contributes to the understanding of the pathogenic potential of the virus.