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1.
PeerJ ; 6: e4617, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29785338

RESUMO

Patterns of habitat selection are influenced by local productivity, resource availability, and predation risk. Species have taken millions of years to hone the macro- and micro-habitats they occupy, but these may now overlap with contemporary human threats within natural species ranges. Wattled Curassow (Crax globulosa), an endemic galliform species of the western Amazon, is threatened by both hunting and habitat loss, and is restricted to white-water floodplain forests of major Amazonian rivers. In this study conducted along the Juruá River, Amazonas, Brazil, we quantified the ranging ecology and fine-scale patterns of habitat selection of the species. We estimated the home range size of C. globulosa using conventional VHF telemetry. To estimate patterns of habitat selection, we used geo-locations of day ranges to examine the extent and intensity of use across the floodplain, which were then compared to a high-resolution flood map of the study area. We captured two females and one male, which we monitored for 13 months between September 2014 and September 2015. Average home range size was 283 ha, based on the 95% aLoCoH estimator. Wattled Curassows selected areas of prolonged flood pulses (six to eight months/year) and had a consistent tendency to be near open water, usually in close proximity to river banks and lakes, especially during the dry season. Amazonian floodplains are densely settled, and the small portions of floodplain habitat used by Wattled Curassows are both the most accessible to hunters and most vulnerable to deforestation. As a result, the geographic and ecological distribution of Wattled Curassows places them at much higher extinction risk at multiple spatial scales, highlighting the need to consider habitat preferences within their conservation strategy.

2.
Environ Toxicol ; 32(4): 1273-1289, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27444704

RESUMO

Parabens are hormonally active chemicals widely used as preservatives in foods and are frequently detected in human fluids and tissues. Therefore, the objective of this study was to determine the effects of maternal butyl paraben (BP) exposure on male sexual development. Pregnant Wistar rats received corn oil (control group), or BP at doses of 10, 100, or 200 mg/kg, subcutaneously, from gestational day 12 until postnatal day 21. Our results demonstrated that developmental BP exposure significantly increased the number of adult Leydig cells and the circulating concentrations of testosterone and attenuated FSH and LH concentrations at 200 mg/kg. BP exposure adversely affected spermatogenesis kinetics at doses of 10 and 200 mg/kg and provoked a decrease in the immunostaining of EsR1 and AR at 200 mg/kg. The sperm motility was impaired at the 10 mg/kg dose, and sperm head abnormalities were increased in all BP dose groups. We suggest that BP impairs testicular structure and function in the rat, affecting sperm quality. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1273-1289, 2017.


Assuntos
Parabenos/toxicidade , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Animais , Receptor alfa de Estrogênio/metabolismo , Feminino , Hormônio Foliculoestimulante/análise , Idade Gestacional , Injeções Subcutâneas , Células Intersticiais do Testículo/citologia , Células Intersticiais do Testículo/efeitos dos fármacos , Hormônio Luteinizante/análise , Masculino , Exposição Materna , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Ratos , Ratos Wistar , Receptores Androgênicos/metabolismo , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Espermatozoides/patologia , Espermatozoides/fisiologia , Testículo/patologia , Testosterona/análise
3.
Neotrop Entomol ; 38(5): 686-7, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19943021

RESUMO

This is the first record of Philornis falsificus Dodge & Aitken parasitizing a species of Falconidae.


Assuntos
Falconiformes/parasitologia , Muscidae/fisiologia , Animais
4.
Neotrop. entomol ; 38(5): 686-687, Sept.-Oct. 2009. ilus
Artigo em Inglês | LILACS | ID: lil-532064

RESUMO

This is the first record of Philornis falsificus Dodge & Aitken parasitizing a species of Falconidae.


Este é o primeiro registro de Philornis falsificus Dodge & Aitken parasitando uma espécie de Falconidae.


Assuntos
Animais , Falconiformes/parasitologia , Muscidae/fisiologia
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