• Rabab Jabbar Sekhi Dept.Microbiology veterinary collage. University of Baghdad, Iraq
  • Ikram Abbas Aboud AL-Samarraae Dept.Microbiology veterinary collage. University of Baghdad, Iraq


Citrobacter Freundii, sheep, bacteria, cultural


The goal of this investigation was to see if there was a virulence gene in Citrobacter Freundii isolates from sheep in Baghdad. Total of (100) clinical specimens were collected as rectal swabs. From December 2020 to March 2021, these specimens were collected from sheep with diarrhoea and normal sheep. Different cultural and biochemical tests were performed, and then a Vitek2 system was used to identify Citrobacter freundii isolates. In this investigation viaB, hlyA, LT, and STp genes prevalence between isolated bacteria was low. When DNA extracted from the eight (8) bacterial isolates, PCR technique was used to amplify the particular viaB primer; following that, gel electrophoresis revealed that only 2 (12.5 percent) of the (8) samples have the (516) bp DNA fragment (viaB gene ) when compare to the allele ladder. To see if hlyA gene[(597) bp fragment] are found in the eight isolate of Citrobacter Freundii , gel electrophoresis revealed that only 4 (50 %) of the (8) samples contain the (597bp) using primers of hlyA When compared to an allelic ladder. For the detection the prescence of LT gene the gel lectrophoresis revealed that only three 3 (37.5%) of the (8) isolates produced the (273bp) DNA fragment. Furthermore, 5 (62.5%) isolates have the particular (166 bp) DNA fragment was shown to be the heat stable toxin gene among isolates.


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How to Cite

Rabab Jabbar Sekhi, & Ikram Abbas Aboud AL-Samarraae. (2022). ISOLATION AND CHARACTERIZATION OF CITROBACTER FREUNDII FROM SHEEP AND DETECT SOME OF THEIR VIRULENCE GENE USING PCR TECHNIQUE. European Scholar Journal, 3(2), 105-113. Retrieved from