Does the rattle of Crotalus durissus terrificus reveal its dietary history?

Abstract

BackgroundEnvironmental devastation threatens the survival of many species, including venomous snakes such as the South American rattlesnake Crotalus durissus terrificus. This observation is based on the decrease of snakes collected and donated to Brazilian research institutes. Nevertheless, some individuals have managed to survive and procreate. The question is how these snakes are adapting in these new environmental conditions.MethodsTo answer it, the carbon-13 level of rattlesnakes and their feed (either laboratory or wild mice) was evaluated by isotope-ratio mass spectrometry. Thus, rattle segments from 16 adults and 15 offspring of captive snakes, and of three wild newborn C. d. terrificus were evaluated as well as 17 Mus musculus mice captured in traps, four live feeder mice and the ration offered to mice at animal houses.ResultsThe isotopic exchange time of the captive adult snakes (n = 16) varied between 33 and 37 months and of captive-born animals (n = 15), until reaching a plateau of equilibrium, varied from 18 to 24 months. Regarding the captured Mus musculus (n = 17), 88.23% (n = 15) were from a C4 environment. Of the six rattle rings from offspring of captured C. d. terrificus, five were from a C4 environment, whereas of the 170 rattle rings studied, 60% originated from a C3 environment and 40% from a C4. The same carbon-13 values were found in captive snakes.ConclusionsBased on the present results, it can be inferred that most C. d. terrificus snakes (60%) fed animals from a C3 environment; birds consist of an alimentary alternative for snakes, as well as rodents, small reptiles and amphibians; different venom compositions among snakes from the same region may be related to the food type; the primary rattle of offspring reflects the maternal diet during gestation; and, finally, the different rattle rings indicate the alimentary history of these animals.Electronic supplementary materialThe online version of this article (doi:10.1186/1678-9199-20-53) contains supplementary material, which is available to authorized users.

Detecting animal by-product intake using stable isotope ratio mass spectrometry (IRMS)

“…This may partially explain the half-life values of 7.89 and 11.44 days found in the AVPR and AVP groups, respectively, which indicate a fast incorporation of animal protein in the sheep serum. Moreover, the tissues of young animals demonstrate faster turnover rates than those of adult animals (Zazzo et al, 2008;Martinez et al, 2014). For the first time, it has been demonstrated that growth and age play a role in dietary 13 C values that are recorded in sheep wool.…”

“…The 13 C/ 12 C and 15 N/ 14 N ratios were measured in a Delta V Advantage Isotope Ratio Mass Spectrometer (Thermo Scientific). The isotopic ratios are expressed as delta per thousand (δ) relative to the international standards Pee Dee Belemnite (PDB) for 13 C and atmospheric nitrogen for 15 N, according to equation 1 (Tieszen et al, 1983;Martinez et al, 2014).…”

“…To quantitatively measure the speed of isotope replacement (turnover) after determining the time interval, the first order exponential function was used, as expressed in equation 2 (Tieszen et al, 1983;Martinez et al, 2014).…”

“…However, there is a gap between the approach used to trace proteins and assessments of their tissue turnover rates (Bahar et al, 2009). Ascertaining the assimilation of stable isotopes in different tissues or biological fluids can define turnover rates, which depend on feeding times (Fossato da Silva et al, 2012;Martinez et al, 2014).…”

Assessment of tissue development in fattening quails using the stable isotope technique

“…Although this technique is currently applied in various animal species, such as piglets, sheep, bovine and snakes (Martins et al., ; Martinez et al., ; Amorim et al., and Jasper et al., ), there is no literature in quails. In fact, up until now this technique has not been applied in quails, as well as during periods of growth and adulthood.…”