Iranian J Parasitol: Vol. 6, No.4, 2011, pp.90-94 Iranian J Parasitol Open access Journal at http:// ijpa.tums.ac.ir Iranian Society of Parasitology http:// isp.tums.ac.ir Tehran University of Medical Sciences Publication http:// tums.ac.ir Short Communication Seroprevalence of Toxoplasma gondii in Sheep, Cattle and Horses in Urmia North-West of Iran S Raeghi1, A Akaberi 2,* S Sedeghi 3 1 Dept. of Basic Sciences, School of Medicine, North Khorasan University of Medical Sciences, Bojnurd, Iran & Zoonotic Diseases Research Center, North Khorasan university of Medical Sciences, Bojnurd, Iran 2 Dept. of Social Medicine, School of Medicine, North Khorasan University of Medical Sciences, Bojnurd, Iran 3 Zoonotic Diseases Research Center, North Khorasan University of Medical Sciences, Bojnurd, Iran (Received 09 Apr 2011; accepted 06 Nov 2011) ABSTRACT Background: Toxoplasma gondii is a zoonotic protozoan parasite found worldwide and responsible for major economic losses in most classes of livestock. This study was aimed to determine the prevalence of T. gondii infection in sheep, cattle and horses in Urmia, north-west of Iran, using MAT. Methods: Blood samples of 276 livestock and 26 horses were collected from July 2009 till April 2010. The data were analyzed by the Chi-square, Fisher's Exact and Cochran’s and Mantel-Haen- szel Tests. The level of significance was set at P < 0.05. Results: Thirty-three (21.1%) sheep, 2 (1.6%) cattle and 3 (11.5%) horses were seropositive to T. gondii. Analysis showed that sheep were 15 times more likely to be seropositive comparing to cattle also 2 times more likely to be seropositive than horses. Conclusion: This study showed seroprevalence of equine T. gondii infection with a considerable rate in sheep in Urmia, northwest of Iran. More comprehensive studies on livestock toxoplasmo- sis are required for further analysis of the parasite reservoir for human infection. Keywords: MAT, Prevalence, livestock, Toxoplasma gondii, Iran *Corresponding author: Tel/Fax: 0098-584-2230927, E-mail: simsadeghi@gmail.com . 90