Figure 2

Histology of the skin of BTV-2 infected sheep exposed to C. sonorensis feeding. Panel A: Skin from the BTV-2 infected sheep at 6 dpi (VH58) shows two sebaceous glands, communicating with a hair follicle (black arrows). Clear spaces around capillaries indicate mild dermal oedema. Additionally there is moderate pericapillary aggregation of plasma cells and lymphocytes (blue arrows). Similar changes were seen in skin sections from BTV infected sheep not exposed to C.sonorensis feeding, suggesting these histological features are most likely a result of BTV infection (H and E; magnification × 20). Panel B: Two granulomas (black arrows) with central neutrophils and eosinophils can be observed in the superficial dermis of the skin at 8 dpi (VH57), most likely as reaction to C. sonorensis feeding as they were not observed in sections from unexposed skin areas. Additionally mild oedema in the dermis and mild to moderate aggregation of plasma cells and lymphocytes are recognised (H and E; magnification × 20).