Department of Bacteriology and Virology, Faculty of Veterinary Science and Animal Husbandry, Orissa University of Agriculture and Technology, Bhubaneswar-751 003 (Orissa)
1 Department of Virology, Post Graduate Institute of Medical Education and Research, Chandigarh-160012.
The MB strain of IBD as commercial vaccine virus successfully adapt to the CEF cell culture system after five blind passages. In vitro studies revealed characteristic CPE like rounding, aggregation of refractile cells, cytoplasmic vaccuolation which intensified with further passages, involving more than 90% cells showing typical CPE after 96 hours PI. Harvested virus showed a TCID50 of 10−2.3, 10−3.4, 10−5.2, 10−4.8, 10−3.1, 10−2.8, 10−2.6 and 10−2.4 per 0.1 ml at 12, 24, 36, 48, 60, 72, 84 and 96 hours PI. The growth curve characteristics of the MB strain of IBDV showed a peak titer at 36 hours PI (TCID50 of 10−5.2/0.1ml) which remained high for a limited period and gradually decline till 96 hours PI. The eclipse period was found to be 10 hours.
MB strain, IBD, chick embryo, cell culture
