EXPERIMENTAL INFECTION OF SHEEP WITH STRAINS OF RIFT VALLEY FEVER VIRUS

El-Nahas, E.M.

doi:10.21608/kvmj.2011.113554

EXPERIMENTAL INFECTION OF SHEEP WITH STRAINS OF RIFT VALLEY FEVER VIRUS

Document Type : Original Article

Author

E.M. El-Nahas

Department of virology, Faculty of Veterinary Medicine, Moshtohor, Benha University, Egypt.

10.21608/kvmj.2011.113554

Abstract

Nine, 5 month old baladi sheep were divided into 3 groups, group I was inoculated with Rift Valley Fever (RVF) virus ZH501strain, group Π was inoculated with RVF virus Smithburn strain, and group ΙΙΙ was non inoculated kept as control. The rectal temperature was recorded and a trial for virus isolation and identification besides following up the antibody response using indirect solid phase ELISA (SPE) were adopted. Group I showed fever continued for 5 to 6 day post inoculation (d.p.i) and successful virus isolation from eye at 3^rd and 7^th d.p.i, from nose at 3^rd d.p.i from rectum at 3^rd, and 9^th d.p.i, whereas plasma and Buffy coat were found to be positive till 5^th d.p.i and sera till 11^th d.p.i, meanwhile the antibody response increased from the 6^th and 7^th d.p.i till the end of experiment. Group Π revealed increase body temperature at 3^rd and 4^th d.p.i and RVF virus disappeared from eye, nose, and rectum, but successful virus isolation from blood continued until the 3^rd and 4^th d.p.i, moreover the antibody response appear at the 4^th and 5^th d.p.i and continued to increase with higher values than group I till the end of experiment. Group ΙΙΙ exposed normal body temperature without virus shedding or antibodies in their sera. In conclusion Smithburn strain can be used as attenuated vaccine or a seed for production of inactivated vaccine as it was more immunogenic than ZH501 strain.