Fig 1.
Tattoo lesions seen in cetacean poxvirus-infected animals.
Tattoo lesion on the thorax of a juvenile male striped dolphin (Stenella coeruleoalba) (a) and tattoo lesion on the thorax of a juvenile female common dolphin (Delphinus delphis) (b).
Fig 2.
Haematoxylin and eosin staining of skin sections positive for cetacean poxviruses by TEM and PCR.
Focal areas of cytoplasmic vacuolation are within the stratum intermedium of the skin (arrows).
Fig 3.
Electron microscopic analysis of cetacean poxviruses.
Viral particles from tattoo lesions of a juvenile male striped common dolphin (c) and a juvenile female harbour porpoise (d). By their size and ovoid shape they resemble parapoxviruses, such as the sheep parapoxvirus displayed for comparison (a). Their surface morphology, however, more resembles a ball of string, typical of orthopoxviruses (b). (Original magnification 92,000x; Bar = 100nm)
Fig 4.
Phylogenetic analysis of the polymerase gene of cetacean poxviruses and reference sequences available from GenBank representing the known genera in the sub-family Chordopoxvirinae.
The phylogenetic tree was constructed by MEGA 5 software and the confidence levels were calculated using bootstrapping (2000 replicates). Only bootstrap values greater than 50 are shown. As seen in the overview (Fig 4a), cetacean poxviruses do not cluster with any other known genus, substantiating the notion that they are to be regarded as a separate one. While parts of the overall topology obtain a relatively low statistical support (after extensive bootstrapping) it resembles the established classification of poxvirus genera and the differences in sequences (both in % and reflected in branch length) support this notion. In more detail (Fig 4b) and taking cetacean poxviruses from other published studies [11,15] into account, six separate species/clusters of poxviruses are recognisable.