Histopathologic lesions in conventional pigs experimentally infected with Haemophilus parasuis serovar 5

Objective: In the present study various tissues of pigs were investigated for the presence of histopathologic lesions after an experimental infection with Haemophilus (H.) parasuis serovar 5. Material and methods: Conventional pigs (n = 36) were divided into a control group B (n = 9) and a challenge group A (n = 27), which was infected intratracheally. Pigs that did not die prior to study termination were euthanized on day 14 post inoculation. Postmortem samples of the lung, heart, liver, kidney, spleen, left tarsal joint capsule and brain were collected. Results: All but one pig with detectable histopathologic lesions (n = 11) showed typical macroscopic changes. Histopathologic examination of all tissue samples identified pyelitis (n = 10), synovitis (n = 7) and meningitis (n = 7) and all those animals were euthanized prior to study termination. No histopathologic lesions were found in pigs of the control group. The correlations between pyelitis and meningitis, pyelitis and synovitis and synovitis and meningitis were significant (p