Studies On Infectious Bovine Rhinotracheitis Virus (Bovine Herpesvirus-1) In Sudan

Abstract

In the present study 78 swab samples were collected for isolation of infectious bovine rhinotracheitis virus (IBR) from cases suffering from infertility, nasal discharges, vaginal discharges, lacrimation and abortion. The IBR virus was isolated from different states of the Sudan; five cases have typical signs of the disease including two from Nyala, two from Atbara and one from West Kordofan. Out of these 78 cattle, 24 serum samples were found to have neutralizing antibodies to IBR virus when tested by SNT, PHA and ELISA, which confirmed the presence of the disease. Three IBR strains (Los Angeles, Kenya and South Africa) were propagated in BKC and other cell culture including LKC, LTC, VERO and BKCL to determine the biological infectivity to these strains in different tissue culture cells. All viruses showed typical CPE to IBR within 24 hours post inoculation. The BKCL and LKC were the best cells in that they produced CPE, which covered 80-90% of cell sheet within 48 hours. 19 Hyperimmune serum was prepared in two rabbits and the serum was collected to be tested by neutralization and passive haemagglutination test for the presence of antibodies. For serosurveillance purposes 856 serum samples were collected from different states of the Sudan. The overall percentage of positive samples was 47.43% (406 samples) tested by PHA. Of 273 samples tested by ELISA 141 were positive (51.65%), whereas 69 out of 94 samples tested by SNT (73%) were positive. The prevalence was found high in states including Jongeli, West and North Kordofan. In comparison between the three serological tests, SNT is recommended to be the technique of choice followed by ELISA, while PHA is a good technique to define the disease.