Detection of virulence-associated genes in biovar 3, the prevalent field strain in different animal species in Egypt.

The current study involved detection of three virulence genes () by PCR in 52 isolates of biovar 3, recovered from different animal species (28 sheep, 10 goats, 9 cattle and 5 buffaloes). Of the 52 strains; 48 (92.3%) isolates carried genes, 51 (98.1%) isolates had genes and 50 (96.2%) isolates were positive for genes. The distribution of the virulence genes is not affected by crossing the original host barriers of the animal species, as the three virulence factors ( and ) detected in 28 isolates obtained from ovine species in a ratio of 26/28 (92.9%), 27/28 (96.4%) and 28/28 (100%), respectively. While 10 isolates originating from goats revealed a ratio of 10/10 (100%), 10/10 (100%) and 9/10 (90%) to the same order of virulence genes. Nearly, similar results of virulence genes detection were obtained in obtained from bovine (8/9, 9/9 and 8/9) and Buffalos (4/5, 5/5 and 5/5), respectively. The high prevalence of virulence-associated genes among the isolates detected from different animal species in Egypt indicates a potential virulence of this bacterium.