Malignant Catarrhal Fever (MCF) is one the most important viral diseases of livestock. Aetiologically, there are 2 forms of the disease, one is associated with Alcelaphine Herpes Virus-1 (AlHV-1) of the wildebeests and the other (SA-MCF) is associated with Ovine Herpes Virus-2 (OvHV-2). In order to detect the epidemiological condition of the disease (Ovine herpes virus-2 in cattle and sheep) in Iran, we collected 100 whole blood samples from clinically ill cattle with MCF, healthy cattle and sheep (more than one year-old). The specimens undergone PCR method in several stages. The 1st stage was performed by pair primers 556 and 775. The reviced a result a band of 422 DNA base pair in 100% of infected cattle and sheep and 75% in healthy cattle. In the 2nd stage, using pair primers 556 and 555, in the Semi-nested PCR, 3 bands of base pairs 238, 340 and 420 of DNA were traced in the specimens. It is noteworthy, that the specimens colleted from sheep and clinically infected cattle with MCF, had all three bands and the healthy cattle specimens had only the 2 DNA band of 420 and 340, which were belonged to OvHV-2 genome.Hassan Momtaz, Farhid Hemmatzadeh, Hadi Keyvanfar and Behnam Abbasia
