Some molecular biology and biological characteristics of the DVE DP-EG-2000 attenuated vaccine strain

Abstract

Duck viral enteritis (DVE) is a serious, acute, contagious disease causing heavily economic loss in the commercial duck production in Viet Nam. Duck enteritis virus is a DNA virus of the Herpesviridae family. In this study, the UL30-UL31 and US7 gene sequences of the DVE DP-EG-2000 attenuated vaccine strain were sequenced, analyzed and compared with those of other reference DVE strains in GenBank. The result of nucleotide (nt) sequence comparison of the UL30-UL31 and US7 genes showed that the DP-EG-2000 strain closely related to other reference DVE strains, sharing high similarity level (98.4 – 100% and 96.5 – 99.6% , respectively).When comparison of the DP-EG-2000 strain with the attenuated DVE VAC strain of China, the nt sequence similarity of UL30-UL31 and US7 gene was 100 % and 96.5%, respectively. The present attenuated DVE DP-EG-2000 vaccine strain in this study was capable for culturingand stable development on the egg embryos at 9–11 days old with the EID50 and ELD50 indexes were 10-4,3 and 10-5,3/0.2 ml, respectively.