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The snake Bothrops jararaca (Squamata: Viperiadae) is a suitable bioindicator of environmental exposure to cadmium: an experimental study

Frossard, Alexandra, Leite, Flaviana L.G., Silva, Eduardo L.F., Carneiro, Maria T.W.D., Júnior, João L.R., Gomes, Levy C., Endringer, Denise C.
Ecological indicators 2019
Bothrops jararaca, bioaccumulation, blood, cadmium, comet assay, demography, environmental exposure, environmental indicators, environmental monitoring, feces, food chain, gall bladder, genotoxicity, heart, ingestion, kidneys, liver, models, pollution, snakes, tail, venoms
Cadmium (Cd) is a highly toxic contaminant causing diverse physiologic damage through the food chain, possibly influencing the demography of wild populations. Thus study aimed to evaluate the feasibility of using Bothrops jararaca as an indicator of Cd contamination. For this purpose, 20 B. jararaca individuals were divided into four groups: a control group and three treatment groups (n=5 in each group), which received Cd-contaminated food (900 mg kg-1) once, twice, or thrice, with a 15-day interval between meals. Animal fitness was evaluated by righting response behavior. In addition, genotoxic effects (comet assay damage index - DI), Cd accumulation in the kidney, liver, heart, gallbladder, fat, venom gland, blood, and tail, and Cd contents in the feces were evaluated. Righting response was negatively related to the number of received meals. Comet assay DI was significantly increased in animals that were fed two or three times. After three contaminated meals, Cd distribution within the body was as follows (µg/g - median): liver (6.24) > kidney (1.88) > venom gland (0.93) > fat (0.85) > gallbladder (0.65) > tail (0.46) > blood (0.45) > heart (0.25). Cd contents in the liver, kidney, and feces were significantly greater in animals that consumed Cd-contaminated food for two or three times. However, Cd accumulation in the liver started to appear after the first meal comprising the highest Cd concentration, while accumulation in the kidney appeared after the third feeding. It can be concluded that B. jararaca is a feasible model for biomonitoring Cd using the liver as a prognostic organ for the bioaccumulation as well as righting response and the damage index as indicators of Cd effects at an experimental level. Field monitoring feces stood out as the most suitable indicator for Cd ingestion by B. jararaca.