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Published on: November 6, 2014
Malformations in neotropical viperids: qualitative and quantitative analysis
S S Sant'Anna1, K F Grego, C A B Lorigados
1Department of Pathology, School of Veterinary Medicine and Animal Sciences, University of São Paulo, 87, Prof. Dr. Orlando Marques de Paiva Avenue, 05508-270 São Paulo, Brazil; Laboratory of Herpetology, Butantan Institute, 1500 Vital Brasil Avenue, 05503-900 São Paulo, Brazil.
Abstract:
Malformations can occur in all living species, but there is little information about anomalies that occur in snakes and their frequency. This study assessed malformations in newborn South American pit vipers (Bothrops jararaca) and South American rattlesnakes (Crotalus durissus) from wild captured pregnant females (240 and 35 litters, respectively). Newborn snakes were measured, weighed, sexed and studied grossly and by radiography for the presence of malformations. Ninety-five malformed pit vipers were identified from 4,087 births (2.3%), while 36 malformed rattlesnakes were found from 324 births (11.1%). Spinal abnormalities were the most common in both species, followed by fusion of ventral scales. Pit vipers showed a greater range of malformations including schistosomia (22.1%), kinked tail (13.7%), bicephaly (3.1%) and hydrocephaly (2.1%).
