Erwinia persicina is a gram-negative pathogenic bacterium that can infect plants and has been isolated from human urine.This study aimed to investigate the effect of E. persicina on small ruminants.In the current study, twenty growing sheep were divided into two groups: a control group (n=10) and an E. persicina-injected (Ep) group (n=10).The Ep group was subcutaneously injected with a single dose of E. persicina bacterial suspension.The animals were carefully examined, and blood and serum samples were collected from both groups at 0, 2, 4, 8, 24 and 48 hpi time points.Clinical examination showed signs of apathy, loss of appetite and ruminal stasis in the Ep group.There were significant decreases in the proinflammatory cytokines (IL-6, IL-1β and TNF-α) and the anti-inflammatory cytokine IL-10 in the Ep group compared to the control group.White blood cell counts were significantly increased at 24 hpi in the Ep group.The immunohistochemical investigation of Toll-like receptor 4 (TLR4) in the lymph nodes did not show any significant differences between the Ep and control groups.E. persicina might have an immunomodulatory effect on sheep, but the mode of infection and the virulence of these bacteria require further investigation.