Toxicon 48 (2006) 401–410 Sexual dimorphism in venom of Bothrops jararaca(Serpentes: Viperidae) M.F.D. Furtado à , S.R. Travaglia-Cardoso, M.M.T. Rocha Laborato´rio de Herpetologia, Instituto Butantan, Av. Vital Brazil, 1500, 05503-900, Sao Paulo, SP, Brazil Received 28 December 2005; received in revised form 14 June 2006; accepted 19 June 2006 Available online 28 June 2006 Abstract Bothrops jararaca is an abundant snake in Brazil, and its venom has been studied exhaustively. The species exhibits adult size dimorphism in which female are larger. We registered the growth in Snout-Vent Length and weight of one litter (with 11 females and 12 males). We compared growth curves and venom profile between male and female of B. jararaca in order to establish the relationship of those characters and sex. Their venoms were analyzed when they were 36 months old, concerning SDS PAGE, protein content, proteolytic, hyaluronidasic, phospholipasic, blood-clotting, edematogenic, hemorrhagic, myotoxic activities, and lethality. Differences in the growth curves of the females and the males were significantly different after the 12th month of age, with the females growing faster. Females produced five times more venom than males. The electrophoretic patterns were variable: the venom from males had more protein bands than females. Venom composition varied significantly between males and females. Venom from females is more potent for hyaluronidasic, hemorrhagic, and lethality activities, whereas venom from males is more potent for coagulant, phospholipasic, and myotoxic activities. The variability of proteolytic and edematogenic activities were not significant. The important sexual dimorphism in body size and mass, amount of venom produced, and venom composition in B. jararaca may reflect a divergence in niche partitioning. r 2006 Elsevier Ltd. All rights reserved. Keywords: Snake size growth; Sexual dimorphism; Venom; Bothrops jararaca 1. Introduction The pitviper Bothrops jararaca is one of the most abundant viperid snake in Brazil, and the most important species concerning the number of acci- dents, since it causes about 90% of all snakebite recorded in its area of occurrence (Ribeiro and Jorge, 1997). This terrestrial lancehead occupies a diversity of habitats including tropical deciduous (broadleaf) forests, open areas, as well as semitro- pical upland forests (Campbell and Lamar, 1989; Sazima, 1992). Clinical manifestations shown by patients bitten by B. jararaca include local and systemic envenom- ing. Local inflammatory process with solid edema is the most frequent sign accompanied by local pain, and local necrosis is another important complica- tion, followed many times by secondary infection (Ribeiro and Jorge, 1990). Concerning systemic ARTICLE IN PRESS www.elsevier.com/locate/toxicon 0041-0101/$ - see front matter r 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.toxicon.2006.06.005 à Corresponding author. Tel.: +55 11 3726 7222x2267; fax: +55 11 3726 1505. E-mail address: fatifurtado@butantan.gov.br (M.F.D. Furtado).