No abstract

Snake venom is an expensive metabolic weapon used for digestion and defense. Detailed studies on the production of venoms are important for the manufacture of antivenoms and for the therapeutic management of snakebites. Bothrops leucurus is one of the snakes of medical importance responsible for a large number of accidents in Northeast Brazil. To establish the correlation between Bothrops leucurus venom (Blv) yield, under captive conditions, and the morphological characteristics (body mass and length), sex and age, 31 specimens were milked during one year, grouped by sex and age (juvenile, adult and long-lived), totaling 106 extractions in that 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 for the choice of animals to antivenom production, and to understand the biological effects of snake venoms under captive conditions.

No abstract

No abstract

Ecological aspects are essential for testing hypotheses about the characteristics, evolutionary processes and behaviour patterns of different taxa. However, for many neotropical lizards, like Gymnodactylus darwinii, such information is scant in the literature. This lizard is endemic to the Atlantic rainforest, occurring from Rio Grande do Norte to São Paulo. Herein, the aspects of trophic ecology, microenvironmental specificity and sexual dimorphism were analysed from 65 collected individuals and 15 sighted individuals in two conservation units: Camucim and Tapacurá, located in São Lourenço da Mata, north‐eastern region of Brazil. The data found classify G. darwinii as a saxicolous lizard, with a preference for rocky outcrops, without sexual dimorphism. According to its trophic ecology, the species is considered a generalist and sit–wait forager. Arthropods, especially Orthoptera and Araneae, dominate the lizard's diet. Neither of these aspects differed between seasons. The present study also shows the importance of the domain conservation, with the aim to provide resources for many vertebrates, especially endemic species.