Application of real - time PCR for evaluation of distribution of equine herpesvirus type 1 in tissues of aborted fetuses

A highly sensitive and specific real-time PCR assay was used for detection and quantitation of equine herpesvirus type 1 (EHV-1) in the different internal organs of aborted fetuses. Tissue samples from 23 aborted fetuses submitted to the Department of Virology of the National Veterinary Research Institute in Pulawy between 2012 and 2013 were used for testing. Total DNA was extracted using a phenol-chloroform-isoamyl alcohol standard protocol. A real-time PCR with forward and reverse primers encompassing a highly conserved region encoding viral glycoprotein B was adapted for diagnosis of EHV-1 infection. The detection limit of the assay was shown to be 6.0x100 of viral DNA copies and the obtained standard curve exhibited a linear range from 100 to 107 molecules. Sixteen out of twenty three aborted fetuses (69.5%) were positive for EHV-1 in real- time PCR. The highest EHV-1 DNA load was obtained for liver (mean Ct value: 15.7) and lung (18.2) samples, while the lowest was in the thymus (29.6) and placenta (28.4).