ARS | Publication request: DETECTION OF EXPERIMENTAL SALMONELLA ENTERITIDIS AND S. TYPHIMURIUM INFECTIONS IN LAYING HENS BY FLUORESCENCE POLARIZATION ASSAY FOR EGG YOLK ANTIBODIES

Submitted to: Poultry Science Association Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: April 4, 2001
Publication Date: August 15, 2001
Citation: Gast, R.K., Nasir,, M.S., Jolley,, M.E., Holt, P.S., Stone,, H. 2001. Detection of experimental salmonella enteritidis and s. typhimurium infections in laying hens by fluorescence polarization assay for egg yolk antibodies. Poultry Science Association Meeting Abstract.

Technical Abstract: This study evaluated the sensitivity and specificity of detection of antibodies in the yolks of eggs laid by experimentally infected chickens by fluorescence polarization (FP) assays using tracers prepared from the O-polysaccharides of Salmonella enteritidis (SE) and S. typhimurium (ST) and an ELISA using an SE flagellin antigen. In 2 trials, groups of specific-pathogen-free laying hens were infected orally with either 1 million or 100 million fu of SE (phage type 13a) or 100 million cfu of ST. Egg yolks were obtained at 5 weekly intervals from infected and uninfected negative control hens. Both ELISA and FP (using SE tracers) detected a high percentage of hens infected with SE, although both assays also detected antibodies in eggs from some hens infected with ST. The FP assay for SE was both more sensitive and more specific than the ELISA. Two different SE tracers for FP displayed different sensitivities and specificities of detection. FP using an ST tracer likewise detected ST infection but cross-reacted with antibodies to SE.