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Visnuvinayagam,Sivam; K,Thangavel; N,Lalitha; S,Malmarugan; Sukumar,Kuppannan. |
Newcastle disease vaccines hitherto in vogue are produced from embryonated chicken eggs. Egg-adapted mesogenic vaccines possess several drawbacks such as paralysis and mortality in 2-week-old chicks and reduced egg production in the egg-laying flock. Owing to these possible drawbacks, we attempted to reduce the vaccine virulence for safe vaccination by adapting the virus in a chicken embryo fibroblast cell culture (CEFCC) system. Eighteen passages were carried out by CEFCC, and the pathogenicity was assessed on the basis of the mean death time, intracerebral pathogenicity index, and intravenous pathogenicity index, at equal passage intervals. Although the reduction in virulence demonstrated with increasing passage levels in CEFCC was encouraging, 20% of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Newcastle disease; Komarov strain; Chicken embryo fibroblast; Newcastle disease vaccine. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822015000300861 |
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