Genotyping of Toxoplasma gondii in Sheep and Cattle Meat Using PCR-RFLP Technique


  • Mahmoud Rahdar Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran ; Department of Parasitology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
  • Leila Arab Department of Parasitology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
  • Ali Reza Samarbaf- zadeh Department of Virology, Faculy of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran



Toxoplasma gondii is an obligate, intracellular parasite, with worldwide distribution. The main source of infection for humans is livestock and meat-producer animals. The relationships between Toxoplasma genotype and biological characteristics of the parasite have already been identified. According to the pathogenicity of the parasite in laboratory animals, Toxoplasma is divided into three genotypes included type I, II and III. Understanding the genotype of the parasite, could help us to predict clinical features and severity of disease. The aim of this study was to identify genotypes of T. gondii in cattle and sheep meat and meat products in Ahvaz city southwest of Iran. One hundred and ninety samples of tongue, heart and muscles of sheep and cattle and meat products, including sausages and burgers, were collected from slaughterhouses and stores. To identify Toxoplasma gondii, DNA were extracted from samples and B1 gene were amplified by specific primers. To determine the genotype of T.gondii, PCR-RFLP was done on positive samples using by amplifying GRA6 gene and endonuclease Msel enzyme. Data analysis showed that the strain of the parasite in all positive samples belonged to genotype I. In this study the predominant Toxoplasma genotype was type I which can cause severe clinical symptoms in immunocompromised patients. Further research is needed to determine the genotype of the parasite in humans and other animals.


Toxoplasma gondii, Sheep, Cattle, Genotyping, PCR-RFLP


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