935 resultados para THREATENED SPECIES
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The aim of this study was to develop an objective method to determine the incidence of pleiomorphisms and its influence on the distribution of sperm morphometric subpopulations in ejaculates of howling monkeys (Alouatta caraya) by using a combination of computerized analysis system (ASMA) and principal component analysis (PCA) methods. Ejaculates were collected by electroejaculation methods on a regular basis from five individuals maintained under identical captive environmental, nutritional, and management conditions. Each sperm head was measured for dimensional parameters (Area [A, (square micrometers)], Perimeter [P, (micrometers)], Length [L, (micrometers)], and Width [W, (micrometers)]) and shape-derived parameters (Ellipticity [(L/W)], Elongation [(L - W)/(L + W)], and Rugosity [(4 pi A/P-2)]). PCA revealed two principal components explaining more than the 96 % of the variance. Clustering methods and discriminant analyzes were performed and seven separate subpopulations were identified. There were differences (P < 0.001) in the distribution of the seven subpopulations as well as in the incidence of abnormal pleiomorphisms (58.6 %, 49.8 %, 35.1 %, 66.4 %, and 55.1 %, P < 0.05) among the five donors tested. Our results indicated that differences among individuals related to the incidence of pleiomorphisms, and sperm subpopulational structure was not related to the captivity conditions or the sperm collection method, since all individuals were studied under identical conditions. In conclusion, the combination of ASMA and PCA is a useful clinical diagnostic resource for detecting deficiencies in sperm morphology and sperm subpopulations in A. caraya ejaculates that could be used in ex situ conservation programs of threatened species in Alouatta genus or even other endangered neotropical primate species.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The vocals are the most conspicuous means of communication between frogs and can express evolutionary relationships among species. Call descriptions of frogs, in general, not standard acoustic parameters which are greatly diversified and usually restricted to comparisons between closely related taxa. The Atlantic Forest is considered one of the biodiversity hotspots of the world, however, it appears that the number of species to be known is still very large. To anurans from this Brazilian Domain, vocalizations are complex and can vary intra and interpopulations. Thus, we presented a quantitative and qualitative analysis of the work descriptions of anuran advertisement call from the Atlantic Forest, available in the literature so far. The frog species from this Domain and their descriptions of the advertisement call have been raised in the literature, organized into families and threat category IUCN Red List Threatened Species. The analysis of the descriptions were made based on the presence of preset parameters. It was observed that the species which the advertisement call is described within the standard are expected within the Brazilian Atlantic Domain, but efforts to describe the advertisement call of frogs of the Atlantic are concentrated in non-threatened species. Among the descriptions works, there is a large discrepancy between the information presented, giving preference to the use of abiotic data in this kind of work, to the detriment of biotic data about choir where the songs were recorded. The results point to the need for advancements in the descriptions of the advertisement of endangered species or to those with deficient information on their conservation status in the Atlantic Forest, and also for greater communication between works that describe vocalizations of frogs. It will be important to know about the state of the art of descriptions works of frogs in other Brazilian Domains, and relate this information with knowledge...
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The aim of the present study was to characterize biopsied and stripped oocytes from the Brazilian endangered teleost pirapitinga (Brycon nattereri) using histochemical and morphological analyses. Biopsied oocytes had a mean diameter of 2.225 mm (modal diameter: 2.312 mm), complete vitellogenesis and a central or slightly eccentric nucleus. Neutral polysaccharides were detected in the follicular cells, zona radiata and yolk globules, while acidic polysaccharides were detected in the follicular cells and cortical alveoli. Ten out of the 19 females treated with two doses of carp pituitary extract (cPE) released oocytes, which were also analysed. Stripping occurred 292 +/- 39 degree-hours after the second dose of cPE and led to a mean spawning weight of 36.2 g, 10% spawning index, 241 oocytes/g of ova, 8222 oocytes/female and 23 oocytes/g of body weight. Stripped oocytes had a mean diameter of 2.33 mm and a mode at 2.375 mm, were weakly adhesive and coloration ranged from wine to brown. Under scanning electron microscopy, stripped oocytes exhibited a single funnel-shaped micropyle located at the animal pole and a zona radiata that measured 7.7 m in thickness with eight pore canals/m(2). Oocyte morphology in Brycon nattereri is similar to that found in other species of the genus, except for the larger size and weaker adhesiveness. These findings provide essential information for a better understanding of the reproductive biology of B. nattereri and the establishment of conservation measures for this threatened species.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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Pós-graduação em Biociências - FCLAS
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Ctenosaura similis is exotic to Florida (Meshaka et al. 2004. The Exotic Amphibians and Reptiles of Florida, Krieger Publ. Co., Malabar, Florida. 155 pp.), whereas Gopherus polyphemus is listed as a species of special concern by the state of Florida (Florida Wildlife Code Chap. 39 F.A.C.), and as a threatened species by the Florida Committee on Rare and Endangered Plants and Animals (FCREPA) (Moler 1992. Rare and Endangered Biota of Florida: Volume III, Reptiles and Amphibians. University Press of Florida, Gainesville, Florida. 291 pp.).
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Serra da Canastra National Park (SCNP) is one of the most important protected areas in the Cerrado biome. Despite its importance to the conservation of rare and endangered species like Brazilian Merganser, two bills were approved in 2010 by Brazil's Chamber of Deputies aiming to reduce SCNP's official boundaries and to transform some of its parts into an Environmental Protection Area (EPA). We evaluated whether such changes would facilitate mining areas to be legally exploited within the park's area, and if those mining areas would represent a threat to Brazilian Merganser populations at SCNP. Results showed that 55% of the mining areas currently within the National Park will be located within the new EPA, and six hydrographic micro-basins inhabited by Brazilian Merganser could be affected by environmental impacts caused by mineral exploitation in those areas. For these reasons, we recommend the two bills be refused at the Federal Senate.
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Habitat use by Sharp-tailed Tyrant (Culicivora caudacuta), and Cock-tailed Tyrant (Alectrurus tricolor) in the Cerrado of Southeastern Brazil. Obligatory grassland birds are dependent on a limited set of native habitats that are disappearing almost everywhere. We examined the use of macrohabitat and microhabitat by two threatened species of flycatchers, the Sharp-tailed Tyrant, Culicivora caudacuta and the Cock-tailed Tyrant, Alectrurus tricolor in a preserved area of cerrado. We generated logistic regression models to explain the presence of these species through variables of microhabitat. Both flycatchers occurred mainly in grassland areas and favored areas with a low density of palms (Attalea geraensis) and trees. The Sharp-tailed Tyrant also favored areas with a high density of low shrubs (< 1 m) and less exposed soil. The positive relationship found between the presence of Sharp-tailed Tyrant and soil cover may indicate the importance of litter and understory vegetation for shelter and food. The conservation of both flycatcher species in the study area should benefit from controlling palm density and the maintenance of grasslands with low shrubs.
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The Adriatic sturgeon, Acipenser naccarii (Bonaparte, 1836), is a highly threatened species due to human activities, particularly overfishing and habitat destruction. Its peculiar ecology and biology (restricted areal and anadromy) makes this species particularly vulnerable. In March 2010 the IUCN has identified the Adriatic sturgeon as a critically endangered species according to the Red List of Threatened Species. Due to its rapid decline, starting from the 80s, at present there is no evidence of natural reproduction in wild environment, which makes the Adriatic sturgeon dependenton captive breeding programs that need to be improved in order to be effective for the survival of the species. For this purpose this study aims to characterize artificial restocking population of Adriatic sturgeon, with both genetic and physiological analysis in order to establish an efficient restocking program for future reproductions. The research is structured on two levels: First genetically, by analyzing 9 microsatellite loci. This gives information relatively about parent allocation and kinship between individuals that were sampled for this study. Hence to predict which reproduction events are the most optimal in terms of incrementing genetic diversity, by the estimation of multilocus pairwise band sharing coefficients. Second step, physiological analysis: testosterone (T) concentration levels in each individual were measured for sexing, without sacrificing the lives of the animals with the use of an invasive examination of the gonads. The combination of interdisciplinary analysis is important to obtain an overall picture in order to indicate the main broodstock participating in reproduction events and future optimal potential participants, in order to ensure a valid management for restocking program and their monitoring.
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Monitoring of herbaceous plants on the Ottawa National Forest (ONF) is used to understand the impact of forest management on understory composition and site conditions. In their planning, national forests are required to take into account management impacts on diversity and ecosystem health. The effect of management on understory species is dependent on various factors, including the intensity of disturbance and the biology of the plant. In the first study in this report, a population of Carex assiniboinensis, a Michigan state threatened species, was monitored for seven seasons including before logging commenced, in order to determine the sedge’s response to a single-tree selection harvest. Analyses provided insights for management of C. assiniboinensis at the stand level over the short-term. In the second study in this report, the use of the cutleaf toothwort (Cardamine concatenata) as a Management Indicator Species on the ONF was reviewed. Data were analyzed to determine the suitability of using C. concatenata to monitor impacts of forest management on site conditions. The various factors that affect understory species population dynamics illuminated the challenges of using indicator species to monitor site conditions. Insights from the study provide a greater understanding of management impacts on understory species across the Ottawa National Forest.