Semen collection and evaluation in free-ranging Brazilian rattlesnakes (Crotalus durissus terrificus)
Publication Type: |
Journal Article |
Year of Publication: |
2007 |
Authors: |
Rogério Loesch Zacariotti, Kathleen Fernandes Grego, Wilson Fernandes, Sávio Stefanini Sant'Anna, Marcelo Alcindo de Barros Vaz Guimarães |
Publication/Journal: |
Zoo Biology |
Publisher: |
A Wiley Company, Inc., Wiley Subscription Services |
Keywords: |
conservation, reptiles, serpentes, spermatozoa |
ISBN: |
1098-2361 |
Abstract:
Abstract 10.1002/zoo.20126.abs Two hundred-ninety species of reptiles are estimated to need urgent action for conservation, with at least 113 threatened species worldwide. The International Union for Conservation of Nature and Natural Resources (IUCN) Red List of Threatened Species includes 80 species of snakes, with six native Brazilian species, a number likely to be an underestimation. Some authors believe that assisted reproduction would be an important tool to improve reproduction in captivity of some reptiles. An efficient technique for semen collection and evaluation is an important step in development of protocols for cryopreservation of semen or artificial insemination in snakes, contributing to the conservation of endangered species. Although these techniques are important, some basic semen parameters are described for four of the ∼2,900 snake species in the world. The Brazilian rattlesnake (Crotalus durissus terrificus) was chosen as a model for semen collection in snakes because it is found quite often in Sao Paulo State. Semen was collected once from each animal by the same investigator during the mating season of this species in Brazil. After antiseptic cleansing of the skin around the cloaca, the snakes were injected subcutaneously with a dose of 15 mg/kg of 1% solution of lidocaine around the cloaca. Semen was collected with ventral massages after cloacal relaxation and directly from genital papilla inside the cloaca. A total of 28 ejaculates from 39 animals were obtained, representing collection efficiency of 71.80%. Semen volume and concentration in Brazilian rattlesnakes ranged from 3–70 µl and from 0.94–2.23 × 109 spermatozoa/ml, respectively. Zoo Biol 0:1–6, 2007. © 2007 Wiley-Liss, Inc.