PREPARATION OF TOXOIDS FROM THE VENOMS OF PAKISTAN SPECIES OF SNAKES (NAJA NAJA, VIPERA RUSSELLII AND ECHIS CARINATUS)

Abstract
Active immunization is required to protect people who are prone to the hazards of snake bites. Toxoid(s) of the snake venom(s) could be used for active immunization. Preparation of snake venom toxoid involves complete detoxification of the venom and retention of maximum immunogenicity. The preparation of highly immunogenic toxoids of 3 kinds of venoms by treatment with increasing concentrations of formalin following the methods of Sadahiro et al. (1970) and Kondo et al. (1971) was described. Guinea pigs weighing 350-450 g and rabbits weighing 1.5-1.6 kg were immunized with each toxoid preparation according to the immunization schedules. No side effects were observed in these animals. Immunized animals challenged with 2-10 MLD [minimum lethal dose?] doses of corresponding venoms were protected. Russell''s viper antiserum has the capacity to neutralize 10 MHD [minimum hemorrhagic dose] of the homologous venom, and E. carinatus antiserum neutralized 15 MHD of its homologous venom.