Molecular detection and genetic diversity of Toxoplasma gondii in different tissues of sheep and goat in Eastern Iran.

This study was designed to detect parasitic DNA in tissues from sheep and goats raised and slaughtered in the southeastern Iran as well as to genetically characterize infecting strains of T. gondii. A total of 240 tissue samples consisting of heart, brain, and diaphragm were obtained from sheep (n=40) and goats (n=40) slaughtered in abattoirs from three provinces located in southeastern Iran including Kerman, Razavi Khorasan, and South Khorasan Provinces between February to October 2015. Nested PCR amplified the B1 and GRA6 genes. To determine the genetic characterization of positive samples, all genotyped positive samples were examined by PCR-RFLP. Sequencing analysis was performed to evaluate the prevalence of type strains (I, II and III). A total of 68(56.66%) tissue samples of sheep and 53(44.16%) from goats were found to be positive for T. gondii B1 gene, that included 11(27.5%) diaphragm, 21(52.5%) heart, and 36(90%) brain of sheep; and 20(50%) diaphragm, 11(22%) heart and 22(55%) brain of goats. Moreover, 22(18.3%) tissue samples of sheep and 20(16.6%) tissue samples of goats were found positive with GRA6 gene for T. gondii. There are three genotypes and mix genotype using mseI enzyme among all positive samples. The results demonstrated the presence of T. gondii DNA in tissues of sheep and goats from southeast of Iran. Control of Toxoplasma infection animal products are important in consumer protection.