Biofilm formation and avian immune response following experimental acute and chronic avian cholera due to Pasteurella multocida

Publication date: Available online 17 July 2018Source: Veterinary MicrobiologyAuthor(s): Briana Petruzzi, Rami A. Dalloul, Tanya LaRoith, Nicholas P. Evans, F. William Pierson, Thomas J. InzanaAbstractPasteurella multocida is the causative agent of avian cholera, an important economic and ecological disease that can present as a peracute, acute, chronic, or asymptomatic infection. Acute avian cholera is associated with encapsulated P. multocida, while chronic and asymptomatic cases of avian cholera may be associated with capsule-deficient P. multocida isolates. We hypothesize that biofilm formation is important for chronic and asymptomatic avian cholera. Experimental infections of chickens with encapsulated, biofilm-deficient P. multocida strain X73, proficient biofilm forming P. multocida strain X73ΔhyaD, and proficient biofilm forming clinical strains 775 and 756 showed that virulence was inversely correlated with biofilm formation. Biofilm-proficient isolates induced chronic avian cholera in the chicken host. Histopathological analysis was used to show that biofilm-proficient isolates induced little inflammation in the lungs, heart, and liver, while biofilm-deficient isolates induced greater inflammation and induced the recruitment of heterophil granulocytes. Putative biofilm matrix material and exopolysaccharide was detected in pulmonary tissue of chickens diagnosed with chronic avian cholera using scanning electron microscopy and a fluorescently-tagged lectin, respectiv...

Source: Veterinary Microbiology - July 18, 2018 Category: Veterinary Research Source Type: research