Evaluate the frequency of foot and mouth disease viral carriers in slaughtered sheep in Mashhad industrial abattoir using RT-PCR


1 Department of Veterinary Research and Biothecnology, Razi vaccine and Serum Research Institute, North East Branch, Mashhad-Iran

2 Graduated from the Payam-e-Noor University of Mashhad, Department of Biochemistry, Mashhad-Iran

3 Department of Investigation, khorasan-Razavi Provincial Veterinary Service, Mashhad-Iran


BACKGROUND: Foot -and- mouth disease (FMD) is endemic in Iran. Molecular techniques for diagnosis of persistent infection or carrier animals have shown a potential ability to improve the detection of a low genome copy number in samples. Objectives: The purpose of this study is to evaluate the frequency of foot and mouth disease viral carriers in slaughtered sheep in Mashhad industrial abattoir using RT-PCR. Methods: Samples were isolated from tonsil of 94 slaughtered sheep analyzed by RT-PCR experiment for the detection of FMD, identification of FMD virus serotypes and at the end nucleic acid sequencing were performed. Results: The results showed that the 23 samples (24/5 percent) were positive for the presence of FMD virus RNA, of which 89.9% of cases are type O and 3 cases of FMD samples did not respond. The results of the 1D genome sequencing of the nucleic acid virus showed that FMD virus of sheep (O/IRN/100/2010Sheep), has 92/02% similarity with the virus (O/IRN/67/2001-2005) and 88/42% similarity with the virus (O/IRN/15/2004-2008). Conclusions: This study showed that the percentage of FMDV sheep carriers in Mashhad slaughterhouse was remarkable. Estimation of the frequency of carrier state in cattle and small ruminants is recommended as a monitor of control plan in the region.


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