The expression of MDA-5 gene in bursa of Fabricius of both two breeds had a rising trend following infection with MDV, which approached significant in broilers at 7 and 21 d.p.i (P = 0.0077 and P = 0.0185) and in Erlang mountainous chickens at 4 and 7 d.p.i (P = 0.0042 and P = 0.0059). Here, IFIH1 is linked to infection.