Genetic analysis of the viral agents causing muzzle crust in small ruminants of Shiraz, Iran.

Abstract

Summary Davari, S. A., M. Sayyari & A. Mohammadi, 2013. Genetic analysis of the viral agents causing muzzle crust in small ruminants of Shiraz, Iran. Bulg. J. Vet. Med., 16, No 3, 159−169. Orf virus (ORFV), the prototype of the genus parapoxvirus (PPV), is the cause of contagious ecthyma, a common viral skin disease of domestic and wild small ruminants with a worldwide distribution. This disease is endemic in Iran and it is sometimes difficult to differentiate it from similar diseases, especially sheep pox, goat pox and peste des petits ruminants (PPR). In this study 50 muzzle crusts were collected from involved sheep and goats from Shiraz suburb during 2011–2012 and PCR was carried out for molecular detection. Twenty-five (50%) of 50 scab specimens were orf positive, 4 (8%) were pox virus positive and 1 (2%) was positive for PPRV. The PCR products were sequenced for nucleotide analysis. Furthermore, orf virus phylogenetic analysis based on 045 gene demonstrated a high degree of identity with other ORFV strains, although there was a slight diversity among the nucleotide sequences. Our study showed that the role of ORFV was greater than the other two viruses for causing muzzle crusts. This is the first molecular study of ORFV in Iran.