Development and validation of a time-resolved fluorescence immunoassay for the detection of anti-Toxoplasma gondii antibodies in goats

Toxoplasma gondii is a worldwide distributed parasite causing abortions and fetal malformations in small ruminants. The aim of this study was to design validate new immunoassay based on the use TgSAG1-GRA8 chimeric antigen for detection anti-T. antibodies serum goats. First, time-resolved fluorescence (TgSAG1-GRA8-TRFIA) developed. In addition, diagnostic performance TgSAG1-GRA8-TRFIA compared with an optimized enzyme-linked immunosorbent assay (TgSALUVET-ELISA) Western Blot (WB), both whole T. tachyzoite antigenic extract. has shown high intra- inter-assay precision, analytical sensitivity accuracy. ROC analysis showed optimal cut-off 217.4 Units Fluorometry (UFT), 92 % 90.48 specificity. A positive statistically significant Spearman’s correlation TgSALUVET-ELISA detected, kappa value 0.83, presenting agreement methods. However, protein cross-reactivity specific anti-Neospora caninum antibodies. Thus, TgSAG-1-GRA8 seems not be ideal option serodiagnosis infection goats unless combined N. parallel. light results obtained, comprehensive existence cross-reactivities between antigens used serological tests employed animal health directed against Toxoplasmatinae parasites should performed.