Résumé : Measurements of muscular microcirculation in horses anaesthetised with halothane were performed by laser Doppler flowmetry. Variations of microcirculation in the compressed and uncompressed triceps brachii were measured when horses were positioned in dorsal recumbency after a prolonged period in lateral recumbency. A significant post ischaemic hyperaemia was recorded in horses which developed a post anaesthetic myositis.