An homogeneous fluorescence polarization assay for detection of Clostridium perfringens type D epsilon antitoxin in serum of goats.
A fluorescence polarization assay (FPA) was developed to detect C. perfringens type D epsilon antitoxin in goat sera. Purified epsilon toxin was labelled with fluorescein isothiocyanate and used as a tracer in the test. Seven goat sera with known concentrations of epsilon antitoxin, as measured by a mouse neutralization test (MNT), were used as positive controls. Sera from 11 colostrum-deprived kids were used as negative controls. The interassay variation of 10 measurements of the 7 positive sera varied between 1.56 and 4.85%. The correlation between the FPA values and concentration of epsilon antitoxin (as measured by the MNT) was 0.90. It is concluded that this test appears to be a good alternative to the MNT, without most of the inconveniences of the later.