Comparison of different serological methods to detect antibodies specific to Neospora caninum in bovine and canine sera

Abstract

Neospora caninum is an apicomplexan parasite responsible for paresis in dogs and abortion in cattle worldwide. Dogs serve as a definitive host, while cattle serve as intermediate host. Many different methods have been developed to detect specific antibodies present in cattle and dog serum. In the present study, the dense granule protein NcGRA6 was incorporated in a latex beads agglutination test (LAT), and compared to other serological methods, including enzyme-linked immunosorbent assay, the direct agglutination test, the immunoblot, and the indirect fluorescent antibody test (IFAT). Using the IFAT as the reference method, 100 sera isolated from Algerian cattle and 100 sera isolated from Algerian dogs, both possibly infected with N. caninum, were used to evaluate the LAT. The sensitivity, specificity, and kappa index were calculated for each host species and assay. For dog sera, the sensitivity and the specificity of the LAT was 76% and 100%, respectively. The McNemar test showed that the LAT was not significantly different from IFAT (P > 0.05). For cattle sera, the sensitivity and the specificity of the LAT were 60% and 100%, respectively. The McNemar test indicated that the LAT was significantly different from IFAT (P < 0.01) and that the LAT was only positive for cattle sera with titers of 1:800 or greater, indicating that LAT can be used for cattle in a clinical context. As well, the LAT has the advantage of being easy and rapid to perform compared to the other assays.

Prevalence of the main infectious causes of abortion in dairy cattle in Algeria

“…A previous study in Algeria indicated that the N. caninum seroprevalence in cattle was 19.6% using IFAT ( 19 ). On the other hand, ELISA gave fewer positive results than IFAT ( 20 ). Therefore, our results were consistent with the previous ones.…”

Serological study ofNeospora caninuminfection in dogs in central China

“…The detection of antibodies against N. caninum has been undertaken worldwide in dogs [ 25 , 28 , 29 , 34 ]. The reference method for this detection is the IFAT [ 5 , 8 , 28 ]. A 1:50 cut-off in IFAT has been recommended and commonly used for canine sera [ 25 , 28 , 34 ].…”

Markers related to the diagnosis and to the risk of abortion in bovine neosporosis

“…These methods include the indirect immunofluorescence test (IFAT), Neospora-agglutination test (NAT), enzyme-linked immunosorbent assay (ELISA), or immunoblotting, among others (Dubey and Schares, 2006;Dubey et al, 2007;Wapenaar et al, 2007). New techniques described recently include a dense granule protein (NcGRA6) incorporated in a latex beads agglutination test (LAT) (Ghalmi et al, 2014) or a disperse dye immunoassay technique for detection of antibodies against N. caninum (Selahi et al, 2013). Most of these techniques have been validated and have proved to be quite sensitive and specific for the detection of infection in cattle (von Blumroeder et al, 2004).…”