Comparison of cutaneous hyperemia in cattle elicited by larvae of Boophilus microplus and by prostaglandins and other mediators.

Blood flow has been measured in bovine skin following the injection of tick antigens and a number of pharmacological mediators; including histamine, prostaglandins and slow reacting substance of anaphylaxis. The greatest increase in blood flow (20 times normal) was recorded with tick antigens and with prostaglandin F2. This mediator may therefore influence blood flow during immune reactions to ticks and during the rapid ingestion of blood by the ticks.