Rao, V.D.P.Srivastava, Gaurangi2019-06-222019-06-222005-08http://krishikosh.egranth.ac.in/handle/1/5810109612In the present investigation, an attempt was made to study the cytopathogenicity of Egg drop Syndrome-76 (EDS-76) virus. In this study, VN1 isolate of EDS-76 virus was cultivated in 9-10 days old duck embryo. When infected allantoic fluid was given to laying birds as an antigen, affected birds appeared dull and depressed with diarrhea. The important characteristic was drop in egg production coinciding with production of soft and thin shelled eggs. The virus was isolated from infected allantoic fluid in primary chicken embryo liver (CEL) cell culture. The cytopathic effects characterized by rounding and degeneration of cells were evident from the first passage itself. May Grunwald and Giemsa stained preparations of infected CEL cells culture revealed eosinophilic intranuclear inclusion bodies with distorted nuclei. AGPT performed using infected duck allantoic fluid and standard and experimentally raised hyperimmune sera against EDS-76 virus, revealed precipitin lines. But CIE was unable to detect the presence of virus in infected duck allantoic fluid and infected cell culture supernatants. FAT performed to detect the presence of EDS-76 virus in infected CEL cell culture exhibit intense intranuclear yellow fluorescence. The haemagglutination property of the virus was studied in infected duck allantoic fluid and infected CEL cell culture. The HI test was performed using hyperimmune serum to confirm the specificity of HA test and a 100% correlation was obtained.ennullThesis