Characterization of Collagen Binding Activity of Strains Isolated from Broiler Chickens.

is the etiological agent for necrotic enteritis (NE) in broiler chickens, which causes a substantial economic loss of an estimated USD 6 billion annually in the global poultry industry. Collagen adhesion is involved in the NE pathogenesis in poultry. In this study, the binding capabilities of chicken isolates of various genetic backgrounds (, , ) to collagen types I-V and gelatin were examined, and the putative adhesin protein gene was investigated at the genomic level. In total, 28 strains from healthy and NE-inflicted sick chickens were examined. The results on collagen adhesin-encoding gene by the quantitative-PCR results indicated that isolates had much lower copies of the detectable gene than isolates (10 , 5 isolates). Most of the virulent isolates demonstrated collagen-binding abilities to types I-II and IV-V, while some strains showed weak or no binding to collagen type III and gelatin. However, the isolates showed significantly higher binding capabilities to collagen III than and isolates. The data in this study suggest that the collagen-binding capability of clinical isolates correlates well with their NE pathogenicity levels, especially for isolates carrying genes encoding crucial virulence factors and virulence-associated factors such as , and . These results indicate that the presence of the gene may be correlated with virulence (particularly for isolates).