Genotype and Phenotype of Echinococcus granulosus Derived from Wild Sheep (Ovis orientalis) in Iran

The aim of the present study is to determine the characteristics of genotype and phenotype of Echinococcus granulosus derived from wild sheep and to compare them with the strains of E. granulosus sensu stricto (sheep-dog) and E. granulosus camel strain (camel-dog) in Iran. In Khojir National Park, near Tehran, Iran, a fertile hydatid cyst was recently found in the liver of a dead wild sheep (Ovis orientalis). The number of protoscolices (n=6,000) proved enough for an experimental infection in a dog. The characteristics of large and small hooks of metacestode were statistically determined as the sensu stricto strain but not the camel strain (P=0.5). To determine E. granulosus genotype, 20 adult worms of this type were collected from the infected dog. The second internal transcribed spacer (ITS2) of the nuclear ribosomal DNA (rDNA) and cytochrome c oxidase 1 subunit (COX1) of the mitochondrial DNA were amplified from individual adult worm by PCR. Subsequently, the PCR product was sequenced by Sanger method. The lengths of ITS2 and COX1 sequences were 378 and 857 bp, respectively, for all the sequenced samples. The amplified DNA sequences from both ribosomal and mitochondrial genes were highly similar (99% and 98%, respectively) to that of the ovine strain in the GenBank database. The results of the present study indicate that the morpho-molecular features and characteristics of E. granulosus in the Iranian wild sheep are the same as those of the sheep-dog E. granulosus sensu stricto strain.

overview of Toxocara cati infection in stray cats in the metropolitan region of Tehran, Iran, and a comparison of two diagnostic methods

Toxocara cati is one of the most important and widespread of the helminth zoonosis. In the present study, helminthosis due to Toxocara cati in 55 stray cats in Tehran was studied by necropsy. In addition, two different diagnostic methods, including serological and coprological tests, for infection with this parasite were compared. The dot-ELISA assay used Toxocaracati crude antigens to evaluate the presence of serum antibodies against the mature nematode. The coprological sedimentation method was carried out to assess the output of eggs. In autopsied cats, 52.7% were infected with T. cati. Seropositive cases were detected in 53.8% of examined cats, whereas the prevalence in feces was 40%. The sensitivity and specificity for dot-ELISA method was 65.5% and 60.9% respectively. In sedimentation method the sensitivity was 69%, and the specificity was 92.3%. The positive and negative predictive values for dot-ELISA and sedimentation were 67.9%, 58.3% and 90.9%, 72.2% respectively. These results suggest that coprological methods for diagnostic and control programs of toxocariosis in cats are the optimal investigations