Fig. 3From: Serological and virological surveillance of avian influenza virus in domestic ducks of the north-east region of BangladeshAmplification of HA (left) and NA (right) gene of avian influenza virus by RT-PCR for sequencing. (MÂ =Â marker, PÂ =Â positive control, NÂ =Â water control, 330 and 18C are two samples)Back to article page