Individual venom variability in Crotalus durissus ruruima snakes, a subspecies of Crotalus durissus from the Amazonian region.

Venoms of six specimens of Crotalus durissus ruruima snakes from the same geographical site in the Brazilian State of Roraima, were individually assayed for their main pharmacological properties. Quantitative and qualitative differences were found and the presence of crotoxin-like isoforms in these venoms was indicated. Our findings corroborate the existence of a considerable intrapopulational variability in C. d. ruruima venoms, and the importance of using a pool of venoms for antivenom production, in general, in order to assure the neutralization of the maximum possible number of toxins from a given species.