Evaluation of live gumboro vaccine prepared from local variant strain for control of infectious bursal disease in Egypt

Abstract

Aim: The present study was designed to evaluate live Gumboro (IBD) vaccine prepared from local variant isolated strain (Egy-IBD Var 2009 Vp2 gene-, partial cds submitted in gen bank at accession no.: JN 118617) for controlling IBD problem in Egypt. Material and Methods: Local isolated variant strain was adapted on Baby Grivet Monkey kidney cell line -70(BGM-70) used for preparation of tissue culture (T.C) live vaccine. T.C IBDV had a titer of 107.5 TCID50/ml (104.5 TCID50 per dose) after five passages in BGM-70 cell culture. Evaluation of prepared vaccine was done in vitro by measuring ELISA, and in vivo by protection % against very virulent or variant field IBD isolated strains. Result: Evaluation revealed that the prepared vaccine was safe; sterile; pure; non-immunosuppressive; and efficient. The Geometric Mean Titer (GMT) of ELISA for the prepared vaccine was 8271 and more than 10000 in compared with different commercial IBD vaccines; while protection percentage gave 96-100%; 92-96% and 96-98% in groups vaccinated with commercial (intermediate; intermediate plus and classical) IBD vaccines; respectively in compared to 96-100% in group vaccinated with local prepared vaccine when challenged with very virulent or variant IBD isolated strains. Conclusion: We can use live T.C. IBD vaccine prepared from local variant isolated virus strain as method for control IBD disease in Egypt.