We investigated levels of plasma progesterone (P4), 17β-estradiol (E2), testosterone (T), and corticosterone (CORT) during gestation and post-birth periods in wild-collected female copperhead snakes (Viperidae; Agkistrodon contortrix). We also sought to determine whether CORT levels at (or near) birth dramatically increase and were correlated with duration of labor and litter size. Specifically...

This study comprises a retrospective analysis of snakebites in the State Amazonas, Brazil, from 2007 to 2017. Data were collected Notifiable Diseases Information System (NDIS). 17,056 recorded Amazonas between and During period, Rio Negro Tefé micro-regions had highest accumulated incidence, while small municipalities such as São Gabriel da Cachoeira, Uarini Alvarães presenting high incidence r...

1. Capital breeding is an ideal reproductive strategy for many ectotherms because it provides a disassociation between feeding and reproduction, a necessary requirement for animals that become anorexic during pregnancy. Among ectotherms, some viviparous snakes (e.g. Viperidae) exemplify the capital breeding strategy because many species (i) do not feed during pregnancy due to behavioural confli...