This study was applied on 631 sheep with ages ranged from 3month to 2 year, from which 60 animals
were suffering from nervous manifestation. A total 45 brain samples were collected from recently
dead and emergency slaughtered sheep and send to the lab. For bacteriological and histopathological
examination. The bacteriological examination results 22 positive samples for L. monocytogenes
(48.8%) with maximum results at 3-6 months of age (57.1%). Moreover, the result showed that the
highest percentages for L. monocytogens isolation was at autumn and winter. Histopathological
examination revealed that there were micro abscesses in the brain. In the same study, trial for
preparation of listeria bacterin from the local strains isolated from the sheep was performed in rabbits
as laboratory animal. Blood samples were collected from the rabbits groups for deferential leucocytic
count and ELISA technique for detection of antibodies after challenge test. The results showed that
there was elevation in antibody titer after vaccination and challenge. In addition, there was elevation in
WBCs, Lymphocytes, Monocytes and Granulocytes in challenged group compared with vaccinated
group. The results of ELISA were highly statistically significant.