Serological Diagnosis and Molecular Characterization of Sarcocystis spp. of Water Buffaloes (Bubalus bubalis)

Abstract

The present study was planned to investigate the prevalence of Sarcocystis spp. among slaughtered water buffaloes (Bubalus bubalus) at Alexandria province. Three hundred blood samples were collected from slaughtered buffaloes (5-7 years old) at El­ Amria and Abbes slaughter houses, Alexandria. Two techniques were used to evaluate the serological-incidence of Sarcocystis spp., Enzyme linked immunosorbent assay (ELISA) and indirect haemagglutination assay (IHA) . Bradyzoites antigen (CZ) was prepared form large-sized Sarcocystis cysts and their protein concentration was estimated to be used in ELISA and IHA assays.

The comparative diagnostic tests of evaluation revealed that 203 (67.6%) of the tested serum samples were seropositive to Sarcocystis spp. by ELISA While, there were 191 (63.6%) positive samples by IHA among naturally infected water buffaloes. ELISA test detected relatively higher percentage of infection with Sarcocystis spp. (67.6%) than those detected by IHA test (63.6 %). The results of sensitivity and specificity ofiHA in relatively to ELISA for detection of antibodies against Sarcocystis was 94% and 100% , respectively. From the obtained results, it was clear that ELISA and IHA tests could be used as reliable screening tests for diagnosis of Sarcocystis spp. infection in living water buffaloes.

For molecular characterization of inter and intra species genetic polymorphism within Egyptian isolates of Sarcocystis spp, PCR and PCR-RFLPs were performed on four macroscopic isC?.lates. The isolates represent two different geographical regions. Alexandria isolates (large and small size of the same host) and Assuite isolates (large and small size of the same host). Molecular differentiation between isolates was performed by using PCR and PCR-RFLPs.