The International Committee on Taxonomy of viruses (ICTV) recognises 10 species in the genus Avipoxvirus , all named according to the first host where they were described. Phylogenetic analysis based on polymorphism of both P4b (major core protein) and DNA polymerase genes indicate the existence of three major clades, A (Fowlpox-like viruses), B (Canarypox-like viruses) and C (Psittacinepox-like viruses), and some recently described subclades . Conventionally, APV was considered to be host-species or host-order specific although many ecological and historical processes may modulate this pattern . For instance, Canarypox virus (CNPV) was thought to preferentially infect passerines, while Fowlpox virus (FWPV) affected chickens and turkeys. Taxonomy of genus Avipoxvirus was based on this concept until recent studies showed that Accipitriformes, Columbiformes, Otidiformes and Passeriformes, can be infected by a high diversity of strains [7–10]. More in depth knowledge about the genetic diversity of APV strains is necessary because combined mutations and recombination among well characterized APV strains have been proposed as the source of the variability which may provide new strains with different pathogenicity . Strain diversity in a single host may be very high, for instance, at least 17 genotypes have been described from houbara bustards, including both CNPV and FWPV genotypes . Because of some APV strains may be found in several bird species the introduction of domestic birds may be a threat for wild birds, especially in isolated populations. Conversely, wild birds may be an infection source for poultry .