Detection of torque teno virus (TTV) in domestic village chickens in Iran

Torque teno virus (TTV) is prevalent worldwide and has been extensively studied in human and some wild and domestic animals. As the studies on TTV in chickens was rare and there was no information about the infection of domestic village chickens with TTV and also structural resemblance of this virus to chicken anemia virus, the frequency of the infection in domestic village chickens in different villages in Isfahan (Iran) was investigated. Sera were collected from ۵۰ chickens. Viral DNA was extracted and subjected to polymerase chain reaction (PCR) using the previously described T۸۰۱ and T۹۳۵ primers that were used for amplification of a highly conserved non-coding region (UTR) of the viral genome in a single round of PCR and Set B primers of conserved region in a nested PCR reaction. Using T۸۰۱ and T۸۳۵ primers TTV or viruses of TTV family were detected in ۱۶ out of ۵۰ sera tested (۳۲%). Fourteen out of the same ۵۰ sera (۲۸%) were positive for TTV using Set B primers. Totally ۲۰ sera were positive using both primers (۴۰%). Ten sera were detected with both sets of primers, six sera with T۸۰۱ and T۹۳۵ primers and only four sera were positive using Set B primers for TTV. Different patterns of the detection of the virus with the two different sets of primers suggests the possibility of the presence of different genotypes of TTV in domestic village chickens and the possibility of the transmission of the virus from human to village chickens and vice versa. This necessitates further investigations.