Selection of Attenuated Vaccine Strain of Duck Paramyxovirus

An attenuated vaccine strain of Duck Paramyxovirus(DPMVa) was selected and obtained by passage serial within SPF chicken embryo fibroblast(CEF), and some biological property of it were detemined. The DPMVa was non-pathogenic to Muscovy ducks without maternal antibody; and was non-viulence through five serial passages in one-day-old Muscovy ducks; TCID50 to CEF stable between 10-6.0~10-6.5·(0.1 mL)-1. The protection rate of the attenuated strain was above 90% when challenged with a virulent strain of DPMV 7 days after vaccination. The results indicated that attenuated vaccine strain had excellent safety, effective immunogenicity and genetic stability, which could be used as a vaccine against DPMV.