TY - BOOK AU - Shazia Afzal AU - Asif Rabbani AU - Muhammed Ajmal ED - ED - Faculty of Veterinary Sciences TI - Isolation & Characterization Of Newcastle Disease Virus Strains In Poultry U1 - 0242,T PY - 1992/// KW - Department of Microbiology N1 - A study was undertaken to isolate and characterize Newcastle Disease Virus Strains involved in field outbreaks. A total of 1000 diseased/dead birds ( broilers, layers arid non-discript birds ) were examined for this purpose. The isolation of the virus was attempted from composite samples comprising lungs, liver, spleen, brain and proventriculus of the suspected birds, which was inoculated in embryonated eggs through allontoic cavity route. Out of the total birds examined only 6(0.06%) yielded ND Virus. All the strains present in allontoic fluid gave a positive reaction to spot haemagglutination test, on fowl RBCs. The isolates were confirmed as Newcastle disease pathogen through a positive reaction to haemagglutination inhibition test conducted with known positive sera against Newcastle disease. Various value values obtained for mean death time (MDT) were 48, 60, 70, 72, 48 and 62 hours for isolates. No. 1, 2, 3, 4, 5, and £ respectively.. Values of intracerebral pathogencity index far isolated No. 1, 2, 3, 4, 5, and 6 were 1.71, 1.68, 1.58, 1.46, 1.7 and 1.65 respectively. The intravenous pathogenecity index varies recorded were 230, 200, 1.91, 1.88, 2.08 and 1.93 for isolate No. 1, 2, 3, 4, 5, and 6 respectively ER -