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

Braz HB (1, 2), Rocha MMT (1), Furtado MFD (1)

(1) Laboratory of Herpetology, Butantan Institute, São Paulo, São Paulo State, Brazil; (2) Laboratory of Ecology and Evolution, Butantan Institute, São Paulo, São Paulo State, Brazil.

Abstract: This study evaluates the mortality and average survival rates of captive female Philodryas olfersii andPhilodryas patagoniensis snakes maintained for venom production. Also, two factors likely to reduce captive survival were studied &endash; 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.

Key words: animal husbandry, snake venom, seasonal variation, body mass index.

ACKNOWLEDGEMENTS

We are very grateful to Silvia R. Travaglia- Cardoso, Laura V. P. Narvaes, and Ana C. Parpinelli for assistance with captive maintenance. We are also grateful to the three anonymous referees for their constructive comments on the manuscript. Thanks are also due to Foundation for Administrative Development (FUNDAP) for the financial support to H. B. Braz.

COPYRIGHT

© CEVAP 2012

SUBMISSION STATUS

Received: September 2, 2011.

Accepted: March 9, 2012.

Abstract published online: March 13, 2012.

Full paper published online: May 31, 2012.

CONFLICTS OF INTEREST

The authors declare no conflicts of interest.

FINANCIAL SOURCE

Foundation for Administrative Development (FUNDAP), São Paulo State, Brazil, provided the financial grants.

ETHICS COMMITTEE APPROVAL

This study was approved by the Butantan Institute Ethics Committee for Animal Use (CEUAIB 482/08).

CORRESPONDENCE TO

Henrique B. Braz, Laboratório de Ecologia e Evolução, Instituto Butantan, Avenida Dr. Vital Brazil, 1500, CEP 05503-900, Butantã, São Paulo, SP, Brazil. Phone: +55 11 3726 7222 ext.: 2014. Fax: +55 11 3726 1505. Email: hbbraz@gmail.com.