الفهرس | Only 14 pages are availabe for public view |
Abstract The objectives of this study are isolation, identification and molecular characterization of BVDV circulating in Sharkia Governorate, Egypt through the following: Trials for isolation of the suspected virus from samples collected from diseased animals, Serological Identification of BVDV in both collected field samples and inoculated tissue culture (after third passages) using Ag-ELISA and indirect IFA, Molecular identification of BVDV using RT-PCR depending on 5`UTR gene and Nucleotide Sequence analysis of amplified 5`UTR gene of the isolated BVDV nucleic acid. In the present study, 280 samples including whole blood, nasal swabs, rectal swabs and sera were collected from 70 diseased cattle and buffaloes. A total of 210 samples including (70 nasal swabs, 70 rectal swabs and 70 heparinized blood from all animals) were used for isolation of BVDV that was carried out using MDBK tissue culture. In addition 70 sera samples were used for direct detection of the virus using antigen capture ELISA (Ag-ELISA). Results of virus isolation revealed out of 210 examined samples, 12 samples showed clear CPE with percent of 5.71%. The results of Ag-ELISA showed that out of 70 tested sera samples, 11 samples showed positive results with percent of 15.71%. The positive sera samples include 4 samples that showed CPE during virus isolation with percent of 5.71% and 7 samples that did not show CPE with percent of 10%. The results of indirect IFA were similar to Ag-ELISA, in which out of 70 harvested tissue culture after third passage, 11 samples showed positive results with percent of 15.71%. All samples (that showed positive results in IFA and submitted to RT-PCR) showed positive results of 5`UTR gene amplification with correct size. Phylogenetic tree pattern after alignments of the sequenced virus revealed that our isolate in this study was closely related to Denmark BVDV strain (2005) with percent identity of 96%. |