Complex sentence: Purpura Haemorrhagica is a rare complication of equine strangles and is caused by bleeding from capillaries which results in red spots on the skin and mucous membranes together with oedema (swelling) of the limbs and the head.
Split into simpler sentences: Purpura Haemorrhagica is caused by bleeding from capillaries which results in red spots on the skin and mucous membranes. It occurs as a rare complication of equine strangles together with oedema (swelling) of the limbs and the head.