Detection of ALV-J replication in chicken MDM from 3 hpi to 36 hpi. A PCR detection with DNA template and ALV-J specific primer. All samples extracted from 3 hpi to 36 hpi produced specific 545 bp fragment. B RT-PCR detection with cDNA template and ALV-J specific primer. C Western blotting analysis shows that samples extracted from 3 hpi produced obvious specific ALV-J envelope protein blots, but the protein blots became weaker at 6 hpi and tended to disappear at 12 to 36 hpi.