Looking for genetic effects of polluted anthropized environments on Caiman crocodilus crocodilus (Reptilia, Crocodylia): A comparative genotoxic and chromosomal analysis

Oliveira, Vanessa Cristina Sales; Viana, Patrik Ferreira; Gross, Maria Cláudia; Feldberg, Eliana; Silveira, Ronis Da; Cioffi, Marcelo de Bello; Bertollo, Luiz Antônio Carlos; Schneider, Carlos Henrique

doi:10.1016/j.ecoenv.2020.111835

Cited by 10 publications

(10 citation statements)

References 50 publications

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“…If high levels of corticosterone are associated with high phenotypic plasticity of C. crocodilus , this is an issue to be examined. This species has the largest distribution among caiman species, and is widespread in the American continent (Marioni et al, 2021), including in highly anthropized environments, such as several small polluted streams that flow through urban areas of Manaus (Oliveira et al, 2021).…”

Section: Discussionmentioning

confidence: 99%

Physiological stress response in free‐living Amazonian caimans following experimental capture

et al. 2021

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When captured, free-living crocodilians respond by hyperstimulation of the hypothalamic-pituitary-adrenal (HPA) axis, which triggers a cascade of downstream events of physiological stress. We examined these responses in two unstressed, and stressed Amazonian caimans, Caiman crocodilus and Melanosuchus niger. Plasma corticosterone levels increased in both stressed caiman species. In M. niger, the levels of this hormone increased 5.2-fold compared with the basal range values, while in C. crocodilus this was only 1.7-fold. After stress, M. niger needed more than 6 h to return its corticosterone levels to basal range values, whereas in C. crocodilus just 0.5 h was enough. Downstream events were characterized by an increase in glucose levels, which is associated with corticosterone increments. Excessive muscle activity resulted in increased plasma lactate content in both species. Lactate levels were also related to plasma calcium concentration, possibly due to the buffering capacity for preventing lactic acidosis. Clearance of excessive lactate load was faster in M. niger (0.5 h) than in C. crocodilus (more than 6 h). Although both caiman species respond in the same way to capture, the amplitude and duration of activation of the HPA axis are different. M. niger may be potentially more sensitive to acute stress than C. crocodilus. On the other hand, C. crocodilus needs more time to recover from the lactic acid load. Our experiment provides a useful diagnostic tool for management and conservation programs, as well as evaluating the impacts of tourism and recreational capture on caimans in the Amazon.

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Section: Discussionmentioning

confidence: 99%

Physiological stress response in free‐living Amazonian caimans following experimental capture

et al. 2021

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“…With the onset of the wet season, they start to disperse, searching for resources. In urban environments, rescues are mostly observed in flood periods, when water bodies are connected to floodplain areas (Negromonte et al 2021), or channels (natural or artificial) connected to the urban drainage system (Oliveira et al 2021), places often overlapped by roads, houses, and other buildings.…”

Section: Resultsmentioning

confidence: 99%

Conflicts between humans and crocodilians in urban areas across Brazil: a new approach to support management and conservation

Mascarenhas-Junior¹,

Maffei²,

Muniz³

et al. 2021

Ethnobio Conserv

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Crocodilian-human conflicts, caused especially by urban expansion and habitat destruction, have been considered one of the main threats to the conservation of these species worldwide. In Brazil, such conflicts have been documented with crocodilian species all over the country. This study identified 400 conflict events in on-line journalistic news between humans and caimans within Brazilian cities between 2016 and 2021. Caiman latirostris (57.3%) was the most common species found in large urban centers in the Northeastern and Southeastern regions. Most encounters in which the date was informed were registered in the wet season (64.5%), and the rescues were mainly carried out by the environmental military police and fire brigades. We outlined management protocols to be undertaken by environmental agencies during crocodilian rescues to minimize animal stress and risk of accidents. The increasingly common interaction between humans and caimans in urban environments is an important alert to envisage best conducts for the coexistence between people and caimans in Brazil and shows the need to invest in public policies to mitigate the negative effects of urbanization on wildlife.

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“…The species of order Crocodylia show karyotype composed exclusively of macrochromosomes probably due to fusions between microchromosomes that resulted in the disappearance of all microchromosomes in this lineage, estimated around 230 Mya ( Deakin and Ezaz, 2019 ). Currently, just six crocodilian species were analyzed by chromosomal mapping with (TTAGGG) n probe: Crocodylus siamensis ( Kawagoshi et al, 2008 ), Caiman latirostris , Caiman crocodiles crocodiles , Paleosuchus palpebrosus , Alligator mississippiensis , and Aligator sinensis ( Oliveira et al, 2021b ). The unique case of the ITS was reported in the karyotype of Caiman crocodilus crocodiles (FN = 60; 24t + 18m/sm) from the Amazon region, Brazil ( Oliveira et al , 2021b ), with (TTAGGG) n signal on centromeric/pericentromeric part of pairs 14, 15, and 16.…”

Section: Its and Chromosomal Remodeling In Insects And Vertebratesmentioning

confidence: 99%

“…Currently, just six crocodilian species were analyzed by chromosomal mapping with (TTAGGG) n probe: Crocodylus siamensis ( Kawagoshi et al, 2008 ), Caiman latirostris , Caiman crocodiles crocodiles , Paleosuchus palpebrosus , Alligator mississippiensis , and Aligator sinensis ( Oliveira et al, 2021b ). The unique case of the ITS was reported in the karyotype of Caiman crocodilus crocodiles (FN = 60; 24t + 18m/sm) from the Amazon region, Brazil ( Oliveira et al , 2021b ), with (TTAGGG) n signal on centromeric/pericentromeric part of pairs 14, 15, and 16. This karyotype differs from the specimens of C. crocodilos from the United States (FN = 62; 22t + 20m/sm), and the presence of ITS could be represented as the signature of the chromosomal rearrangements that occurred during the chromosomal evolution of C. crocodilos ( Oliveira et al , 2021b ).…”

Section: Its and Chromosomal Remodeling In Insects And Vertebratesmentioning

confidence: 99%

Telomere organization and the interstitial telomeric sites involvement in insects and vertebrates chromosome evolution

et al. 2022

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Telomere has a central role in chromosomal stability events. Chromosome ends organized in telomere-loop prevent activation of DNA damage response (DDR) mechanisms, thus keeping the chromosome structure organized. On the other hand, free chromosome ends, dysfunctional telomeres, and interstitial telomeric sequences (ITS) can trigger chromosome rearrangements. Here, the telomere organization, function, and maintenance mechanisms, in addition to ITS types and their involvement in chromosome changes, were revisited. Despite a general (TTAGGG) n sequence being present in vertebrate telomeres, insects show more diversification of their telomere motif. The relation between ITS and chromosome rearrangements was observed in insects and vertebrates, demonstrating different types of genome organization and distribution. Some ITS cannot be considered relicts of chromosome rearrangements because probable they were inserted during a double-strand break repair mechanism. On the other hand, the involvement of telomere sequences participating or triggering chromosome rearrangements or organizing satellite DNA components in several species groups is evident. The genomic assembling advances and applying other methodologies over ITS, and their flanking regions, can help to understand the telomere participation in the chromosomal evolution in species groups with highly diversified karyotypes.

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Looking for genetic effects of polluted anthropized environments on Caiman crocodilus crocodilus (Reptilia, Crocodylia): A comparative genotoxic and chromosomal analysis

Cited by 10 publications

References 50 publications

Physiological stress response in free‐living Amazonian caimans following experimental capture

Physiological stress response in free‐living Amazonian caimans following experimental capture

Conflicts between humans and crocodilians in urban areas across Brazil: a new approach to support management and conservation

Telomere organization and the interstitial telomeric sites involvement in insects and vertebrates chromosome evolution

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