Some adhesins of avian pathogenic Escherichia coli (APEC) isolated from septicemic poultry in Brazil

Abstract

Three hundred and fifty strains of E. coli isolated from septicemic poultry from seven states of Brazil were examined for presence of nine adhesion-encoding genes, hemagglutination and adherence to chicken tracheal cells (in vitro). Analysis of the strains by colony hybridization tests demonstrated that 93.7% of the isolates were fim +, 17% pap+ and 5.7% were sfa+. The mannose sensitive fimbriae occur with similar frequency in APEC isolated from all Brazilians states, while significant differences among pap and sfa genes distributions were observed. The results showed that 0.85% and 0.28% of APEC were positive for genes that encoded enteroaggregative adhesins and EPEC adherence factor, respectively. None of APEC was positive for DA, afa, Bfp and Eae probes. The adherence to chicken tracheal cells showed 96% positive strains, while hemagglutination assays showed 26.5% of the isolates were mannose sensitive and 21.7% were mannose resistant.

Peran Hemaglutinin dan Hemolisin pada Escherichia coli Sorbitol-negatif Isolat Burung Puyuh pada Proses Infeksi Secara in Vitro

“…Hemaglutinin pada Escherichia coli patogen berperan dalam proses koloni dan adesi pada sel inang (Bohach dan Snyder, 1985), serta memperparah penyakit (Edwards et al, 2000). Keberadaan hemaglutinin pada Escherichia coli isolat asal unggas telah dilaporkan oleh Knobl et al (2006) Hemolisin berperan Escherichia coli berperan meningkatkan pertahanan terhadap antibodi dan menghindar dari sel-sel fagosit serta memperparah penyakit (Mittal et al, 2014). Keberadaan hemolisin pada Escherichia coli isolat asal burung puyuh telah dilaporkan Roy et al (2006).…”

Virulence and molecular aspects of Bordetella avium isolated from cockatiel chicks (Nymphicus hollandicus) in Brazil

“…A hemagglutination assay using guinea pig erythrocytes was conducted as described by Temple et al (1998), but the strains were cultured on Colonization Factor Agar (CFA) at 37 8C for 24 h as described by Knö bl et al (2006).…”

“…A tracheal attachment assay was conducted as described by Knö bl et al (2006) using the tracheal rings (transverse 2 mm fragments) obtained from one euthanized cockatiel chick (N. hollandicus). The bacterial strains were grown overnight on Smith-Baskerville at 37 8C for 24 h.…”