Philodryas olfersii (Lichtenstein, 1823) and P. patagoniesis (Girard, 1857) are species of colubrid snakes of the opisthoglyphous series restricted to South America. Several accidents caused by these snakes have been reported and they are mainly characterized by marked effects at the site of bite, such as pain, swelling and hemorrhage. Such accidents are similar to those caused by snakes of the genus Bothrops, and thereby patients bitten by Philodryas sp. are frequently treated with Bothrops antivenom. Since few studies have dealt with the characterization of these venoms, our aim was to study the venoms of P.olfersii and P.patagoniensis. They presented protein contents between 75 and 90%. No defibrinogenating activity could be detected when tested in mice. Experimental envenomation induced by Polfersii or P.patagoniensis evoked intense pain symptoms in mice, but the venom of P.patagoniensis was more active. Both venoms presented minimum edematogenic doses around 1 µg/mouse, peaking at 30 mm. The onset of hemorrhagic activity was rapid, and their minimum hemorrhagic doses were alike.The toxic activity of both venoms was similar, showing values around 60.0 µg/mouse, which are comparable to those of Bothrops Wagler, 1824 venoms.
Local and systemic activities; toxics secretions; Xenodontinae
