Molecular characterization and phylogenetic analysis of orf virus isolated from goats in Sokoto metropolis, Nigeria

Aim: The aim of this study was to molecularly characterize orf virus isolated from clinical infections in goats in Sokoto metropolis. Materials & methods: Embryonated chicken eggs were used to isolate orf virus according to the established protocol. Viral DNA was extracted and full coding region of B2L gene was amplified by polymerase chain reaction, sequenced and blasted for identification and phylogenetically analyzed. Results and discussion: The B2L gene sequences of the isolate showed slight variability (96-98.7%) with the reference sequences as it clustered within the same clade with Korean, Zambian and Ethiopian strains, signifying a close genetic relationship. Unique amino acid substitutions were noted. This is the first genetic characterization of B2L gene of orf virus circulating in Nigeria. Conclusion: This study has provided in sight into the genetic diversity of orf virus in the study area. Lay abstract: Contagious ecthyma has for long been affecting the goat and sheep population in Nigeria leading to huge economic losses to livestock farmers through death and poor market value of the affected animals. Recently, increased death due to this disease has been reported in north-central Nigeria, but the nature of the disease-causing agent has not been reported yet. It is the aim of this study to understand the nature of the virus causing the disease in goats in Sokoto using molecular biology techniques so as to facilitate better vaccine design for the effective control of the disease in Nigeria.