Maintaining rear-fanged snakes for venom production: an evaluation of mortality and survival rates for Philodryas olfersii and P. patagoniensis in captivity

This study evaluates the mortality and average survival rates of captive female Philodryas olfersii and Philodryas patagoniensis snakes maintained for venom production. Also, two factors likely to reduce captive survival were studied - body condition at admission and seasonality. Mortality peaks occurred during the second month in captivity. More than half the individuals were dead at the end of the third month. This suggests that the first three months in captivity are the most critical in terms of survival and adaptation. Females collected and admitted during spring and summer lived less time than those collected in autumn and winter. As gravidity and egg-laying occur during spring and summer, we suggest that the lower survival rates in these seasons may be due to high costs and stress involved in these reproductive events. Unexpectedly, body mass and body condition were poor predictors of survival in captivity. Our results have important implications in maintaining snakes for venom production. We propose some prophylactic measures to minimize the deleterious impacts of captivity during the adaptation period.(AU)

Analysis of the ontogenetic variation in the venom proteome/peptidome of bothrops jararaca reveals different strategies to deal with prey

Previous studies have demonstrated that the pharmacological activities displayed by Bothrops jararaca venom undergo a significant ontogenetic shift. Variation in the venom proteome is a well-documented phenomenon; however, variation in the venom peptidome is poorly understood. We report a comparative proteomic and peptidomic analysis of venoms from newborn and adult specimens of B. jararaca and correlate it with the evaluation of important venom features. We demonstrate that newborn and adult venoms have similar hemorrhagic activities, while the adult venom has a slightly higher lethal activity in mice; however, the newborn venom is extremely more potent to kill chicks. The coagulant activity of newborn venom upon human plasma is 10 times higher than that of adult venom. These differences were clearly reflected in their different profiles of SDS-PAGE, gelatin zimography, immunostaining using specific antibodies, glycosylation pattern, and concanavalin A-binding proteins. Furthermore, we report for the first time the analysis of the peptide fraction of newborn and adult venoms by MALDI-TOF mass spectrometry and LC-MS/MS, which revealed different contents of peptides, while the bradykinin potentiating peptides (BPPs) showed rather similar profiles and were detected in the venoms showing their canonical sequences and also novel sequences corresponding to BPPs processed from their precursor protein at sites so far not described. As a result of these studies, we demonstrated that the ontogenetic shift in diet, from ectothermic prey in early life to endothermic prey in adulthood, and in animal size are associated with changes in the venom proteome in B. jararaca species.

Some aspects of the venom proteome of the Colubridae snake Philodryas olfersii revealed from a Duvernoy's (venom) gland transcriptome

We investigated the putative toxins of Philodryas olfersii (Colubridae), a representative of a family of snakes neglected in venom studies despite their growing medical importance. Transcriptomic data of the venom gland complemented by proteomic analysis of the gland secretion revealed the presence of major toxin classes from the Viperidae family, including serine proteases, metalloproteases, C-type lectins, Crisps, and a C-type natriuretic peptide (CNP). Interestingly, the phylogenetic analysis of the CNP precursor showed it as a linker between two related precursors found in Viperidae and Elapidae snakes. We suggest that these precursors constitute a monophyletic group derived from the vertebrate CNPs.