The Accuracy of Developed Peroxidase Toxoplasma gondii IgG ELISA Plates for Evaluating Toxoplasmosis in Sheep

Abstract

One of the main sources of human toxoplasmosis is mutton from chronically infected sheep. The accuracy of the developed T. gondii IgG ELISA plates (IgG/POD) were evaluated. A total number of 311, both blood and the matching tissue sheep samples were collected. Serological detection of toxoplasmosis in all samples with IgG/POD plate compared with the Latex agglutination test (LAT), Sabin Feldman dye test (SFDT), and conventional ELISA. The identical tissue samples to seropositive sera were bio-assayed through a mouse viability test to define the LD50 and LD100, and the histopathological assay was also done. The designed IgG/POD ELISA plate confirms higher accuracy against the total positive percentage of IgG compared to a conventional ELISA (44 and 38%). It also recognized the highest rates of IgG (48 and 26%). LAT-positive serum markers were (53, 33, and 49%) versus SFDT (68, 41, and 63%), while (12.5, 22 and 14%) were the result percentages of positive microscopic exam of ewes, rams, and total sheep. The mice viability test successfully isolated tachyzoites from 11(9 ewes and two rams) isolates. However, bio-typing detected (27%) of isolates of Type II and (73 %) of isolates of Type III. Finally, tachyzoites and tissue cyst stages were histo-pathological demonstrated within the experimentally infected mice and mutton tissues, respectively. In this study, the IgG/POD developed plate confirmed greater accuracy against IgG compared to the reference ELISA test. This test, along with mouse viability and the histopathological confirmation, are excellent bio-indicators reflecting the zoonotic hazard via the spotted mutton harboring T. gondii virulent strains.