Production of freeze dried inactivated vaccine for bovine root virus

In this study, freeze dried inactivated bovine rota virus [BRV] vaccine was prepared on Madin Darby Bovine Kidney [MDBK] cell line using Nebraska strain virus. The initial titre was 10[8] TCID[50] /ml and the virus was inactivated by using binary ethyleneimine at concentration 1%. Gelatine was used as adjuvant 0.5% at the final concentration. In activated BRV vaccine was proved to be safe and potent when inoculated in mice, guinea -pigs and calves. Immune response of vaccinated calves was studied using serum neutralization test [SNT] and Enzyme Linked Immunosorbent Assay [ELISA]. The titre of BRV antibodies started to appear at 2 weeks post vaccination [WPV] reached 0.8 +/- 0.17 log[10] with a peak 1.65 +/- 0.17 at f 6 WPV and gradually decreased 0.75 +/- 0.17 log[10] at 24 WPV

isolation of non cytopathogenic strain of bovine virus diarrhea-mucosal disease virus in Egypt

Primary investigation for prevalence of the NCP strain of BVD-MD virus in Bk cultures resulted in the detection of NCP virus from 2 out of 3 kidneys brought from Cairo Abattoir on 3 successive weeks. Primary cultures were maintained for 2 weeks, then two other subpassages were made to allow virus growth in kidney cells if present. Challenge of the 3rd BK subculture by 100-200 TCID50 of the cytopathic [CP] strain of BVD-MD indicated interference [Homologous interference] in cell cultures of two bovine kidneys, no interference was detected in the 3rd BK culture. Serum neutralization test for the two isolated viruses [interfering viruses] using hyperimmune serum of BVD-MD [C24 V] virus indicated that the two NCP isolated strains were BVD-MD virus. This is as CP strain of BVD-MD induced it is specific CPE in cells inoculated by virus-serum mixture after challenge and CPe was inhibited in control cultures previously inoculated by each of the NCP strains. Specific CPE of BVD-MD challenge virus [CP-Iman/248] appeared in virus controls