Changes in cutaneous blood vessels in bovine dermatophilosis.

Abstract Skin sections from cattle affected with chronic dermatophilosis were examined for histopathological changes in the cutaneous blood vessels. The venules and capillaries in the upper dermis showed a 3-fold increase in number and were dilated, congested and filled with cells, while arterioles and vessels in lower levels of the dermis were normal. Just over 11 per cent of the blood cells in these vessels were leucocytes, composed of 72·2 per cent polymorphonuclear cells and 27·8 per cent mononuclear cells. The escape of leucocytes from the cutaneous vessels into the dermal stroma appears to take place at a level between the sebaceous gland and the dermal papillae.