Influence of size, sex and age on venom yield of <em>Bothrops leucurus</em> (Serpentes, Viperidae) in captivity conditions
The breeding of medically important snakes is of great value, not only for the production of serums, but also for scientific studies aimed at the maintenance and well-being of animals in captivity. The present study aimed to establish the correlation between body size, sex and age in the venom production of Bothrops leucurus snakes, when manually milked under intensive captivity conditions, for one year. Were used 31 specimens kept in the Herpetology laboratory of Instituto Butantan, grouped by sex and age (young, adult and old). Biometric data (weight and length) and solid and liquid weight of venoms extracted from each fang were recorded, totaling 106 extractions in the period. We evaluated the electrophoretic profile (SDS-PAGE) under reducing conditions, the 50% lethal dose (LD50) and the minimum coagulant dose (DMC) of the extracted venoms. The body size was positively correlated with venom production in B. leucurus snakes. Regardless of sex and age, the venom showed no differences between liquid and solid composition or between right and left fang, however, the production of venom in females was twice the one found in males and more lethal. The clotting ability was lost as the animals aged, indicating that older snakes are not the best choice for venom pools in the production of antivenoms. These results are important to choose of serum production animals, and to understand the composition of snake venoms under captive conditions.