The mass of venom injected by two elapidae: the taipan (Oxyuranus scutellatus) and the Australian tiger snake (Notechis scutatus).

Using an enzyme immunoassay technique, a new method for measuring, in vivo, the mass of venom injected during snake bite, is presented. The venom injected into mice (as prey) and the venom left on the skin surface during bites by the two Australian Elapidae, the Taipan (Oxyuranus scutellatus) and the Tiger Snake (Notechus scutatus) has been measured. Venom delivery patterns vary significantly between these two species. In the case of the Tiger Snake (a total of 45 bites studied) the mean mass of venom injected in a first bite was 12.7 mg (S.E. 3.4 mg, median 8.1 mg); an average mass of 0.8 mg (S.E. 0.4 mg, median 0.17 mg) was left on the skin surface. A second bite delivered by the same snake yielded a mean venom mass only 27% of the first. In the case of the Taipan (a total of 24 bites) the mean venom mass injected in the first bite was 20.8 mg (S.E. 6.4 mg); with an average of 0.9 mg (S.E. 0.5 mg) left on the skin surface. In contrast to the situation observed with Tiger Snakes, second and third bites delivered in a rapid sequence yielded increasing masses of venom. The mean delivered in the third of a sequence of three bites was 48.8 mg (S.E. 23.8 mg). The ranges of venom mass, by species and by the sequence number of the bite, are also presented. In 66 of the 69 experimental bites studied in this report, venom could be easily detected, the species identified, and the absolute mass of venom measured.