932 resultados para Aves - Parasito


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The diet study of birds has contributed historically as a model for use to understanding ecological patterns and strategies used by several other groups of vertebrates, which are observed in season patterns and temporal availability of resources, and other. This study has as objective generate information concerning the diet of insectivorous birds during rainy season and dry season, as well as analyze Index food importance, niche overlap, niche breadth, electivity, and seasonal availability of prey. The study was conducted in a fragment of about 270 ha (center coordinates and 5 º 53'S 35 ° 23'W). The sampling of birds occurred between March 2008 and December 2009 in three pre-established trails. Catches of birds were performed using 10 mist nets placed in line, where each trails was sampled once a month. Samples of pellets were obtained by means of tartar emetic. Sampling of availability of prey occurred between February 2009 to December 2009. We used two methods of sampling (pitfall traps and Shake cloths). We captured 269 individuals of 21 species of insectivorous birds. We collected 4116 invertebrates of which 3259 in the rainy season and 857 in the dry season. We obtained 174 samples stomach, where 10 species were exclusively insectivorous diet, nine fed on insect/plant material, an insect/plant material/vertebrate and one for insect/vertebrate. During the rainy season was observing difference between the consumption of items with higher food importance. The Coleoptera was item with higher food importance (73%), followed by Formicidae (7%) and Araneae (6%). During the dry season, no difference was found difference between the consumption of items with higher food importance. The Coleoptera was item with higher food importance (34%), followed by seeds (29%) and Formicidae (18%). The highest levels of niche overlap occurred during the rainy season, while the dry season was characterized by high levels of niche 11 segregation. This indicates that the local insectivorous birds community was structured differently between periods. No was found correlation between the values of niche breadth to the mean weight of the body size. We observed seasonal patterns in prey availability, with the peak availability of invertebrates observed seasonal patterns in rainy season. The insectivorous birds selected the same species richness during both periods, showing a specialized diet. Thamnophilus pelzelni was the only species that had their diet influenced by seasonality. Regarding the overall diet of insectivorous birds, observed a high consumption of prey, whose food availability caused the birds could invest and increase their food resources

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Neste trabalho, objetivou-se avaliar o desempenho, a sobrevivência e a efetividade de reversão de larvas de tilápia do Nilo (Oreochromis niloticus L.) alimentadas com rações contendo níveis crescentes de inclusão de farinha de vísceras de aves (FVA). Utilizou-se 500 larvas de tilápia do Nilo com dois dias de idade, distribuídas em um delineamento inteiramente casualizado com cinco tratamentos e cinco repetições, sendo a unidade experimental constituída por um aquário de 30 L com 20 larvas. Foram elaboradas cinco rações com cinco níveis de inclusão de FVA ( 0; 20; 40, 60% e 60% mais lisina sintética). Foram elaboradas rações isocalóricas, isocálcicas, isofosfóricas e isoprotéicas, com 60mg de a-metiltestosterona/kg, 38,6% de proteína digestível e 3.700 kcal de energia digestível/kg, de modo que a ração com inclusão de lisina foi isoaminoacídica para lisina em relação à ração sem a inclusão de FVA. O arraçoamento foi realizado quatro vezes ao dia, ad libitum. Ao final, foram avaliadas as médias de peso final (PF), comprimento total (CT), sobrevivência (SO) e efetividade de reversão (ER). Foi observado aumento linear no PF e CT com o aumento da inclusão da FVA na ração, enquanto, para SO, a ração sem FVA foi inferior às demais. As rações sem inclusão de FVA e com 20% de inclusão de lisina proporcionaram PF e CT médios inferiores e somente a ração sem FVA foi inferior para SO. Conclui-se que a FVA pode ser utilizada em rações para a tilápia do Nilo durante a reversão sexual.

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Trypanosoma cruzi infection was evaluated in 390 resident individuals in different rural communities of Caicó municipality, State of Rio Grande do Norte (RN). Of 28 investigated communities the soroprevalence of T. cruzi infection was 2.8% in eight rural communities individuals. The epidemiological characteristics of seropositive shown that the age ranged from 22 to 64 years, being significantly raised from 31 years (90.9%). The female gender was predominant and low education degree. Those individuals reported that they never donated blood, but they had direct contact with triatomines bug. The isolation of the parasite was performed by blood culture and xenoculture methods to determine the genetic variability of the samples. Twenty seven T. cruzi isolates were analyzed by RAPD as genetic marker using three random primers (M13-40, gt11-F and L15996). The T. cruzi isolates showed 73.7% of shared bands considering the average obtained with the three primers, and were genetically well correlated. Using this marker it was possible to separate the populations of the parasite in three distinct groups. The first group composed by isolates obtained of triatomines and humans from four different districts (Caicó, Caraúbas, Serra Negra doNorte and Governador Dix-Sept Rosado); the second contained isolates obtained of triatomines of two different species (T. brasiliensis and P. lutzi) captured in Caraúbas and Serra Negra do Norte. The third grouped isolates obtained from humans of Angicos and Caicó municipalities. In different localities of distinct mesoregions, State of RN, a profile genetic well correlated was identified among all isolates and the presence of three distinct groups of the parasite circulating among vertebrate and invertebrate hosts

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Determinaram-se os níveis nutricionais de cálcio (Ca) para aves, machos e fêmeas, da linhagem ISA Label, nas fases inicial (um a 28 dias), crescimento (28 a 56 dias) e final (56 a 84 dias). Foram realizados três ensaios, um para cada fase, e, em cada ensaio, 480 aves com idade correspondente à fase de criação foram alojadas em 24 unidades experimentais com áreas de abrigo e de pastejo. Foi utilizado delineamento inteiramente ao acaso, em esquema fatorial 4x2 (Ca e sexo), totalizando oito tratamentos com três repetiç ões de 20 aves. Avaliaram-se: ganho de peso (GP); consumo de dieta (CD); conversão alimentar (CA); teores de fósforo (PT), de cálcio (CaT) e de cinzas na tíbia (CT) e resistência à quebra óssea (RQO). Na fase inicial, recomenda-se 1,16% de Ca na dieta, para aves de ambos os sexos, na fase de crescimento, 0,78 e 0,88% de Ca para machos e fêmeas, respectivamente, e, na fase final, 0,69% de Ca na dieta para ambos os sexos.

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How ecologically similar species are able to coexist has always generated great interest in the scientific community. Classical niche theory predicts that species coexistence is only possible when they segregate in at least one dimension of the ecological niche, thus leading to ecological differentiation among species. However, recent work has shown that species that are more similar in some ecological traits are the ones more prone to be able to coexist (environmental filter). The knowledge of how these forces act shaping ecological communities can reveal co-existence strategies, providing important information for management and conservation of the species. This study tested these hypotheses using a pair of coexisting species of Herpsilochmus, H. pectoralis and H. sellowi. In this study I use high resolution (50 x 50 m) ecological niche models to Identify which environmental factors best predict species occurrence. Next, I calculate the overlap in habitat use by species and build null models to test the hypothesis of spatial niche segregation. In addition, I obtain the selectivity parameters of habitat use to test whether the species H. pectoralis (larger body size) is less selective than H. sellowi (smaller body size) as stated in the literature for other species. The results reject the ecological equivalence among species, revealing that the species of Herpsilochmus explore the habitat differently, having different environmental niches. The hypothesis of environmental filter was not observed in my analysis, the observed overlap in habitat use among species was lower than expected by chance. Evidence that Herpsilochmus are spatially segregating reinforces the hypothesis of interspecific competition as the predominant force in the selection of microhabitat of the species. However, more data and experiments are necessary to state categorically that the observed pattern is a result of current or past competition

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For a long time, we believed in the pattern that tropical and south hemisphere species have high survival. Nowadays results began to contradict this pattern, indicating the need for further studies. Despite the advanced state of the study of bird population parameters, little is known about their variation throughout the year and the factors affecting them. Reproduction, for example, is one factor that may alter adult survival rates, because during this process the breeding pair allocates resources to maintain itself to maintain offspring, making itself more susceptible to diseases and predation. The aim of this study was to estimate survival and population size of a Central and South America passerine, Tachyphonus rufus (Boddaert, 1783), testing hypotheses about the factors that define these parameters. We performed data collection between Nov/2010 and ago/2012 in 12 ha plot, in a fragment of Atlantic Forest in northeastern Brazil. We used capture-mark-recapture methods to generate estimates using Closed Design Robust model in the program MARK. We generated Multi-state models to test some assumptions inherent to Closed Robust Design. The influence of co-variables (time, rain and reproductive cycle) and the effect of transient individuals were measured. Capture, recapture and apparent survival parameters were defined by reproductive cycle, while temporary dispersal was influence by rain. The estimates showed a higher apparent survival during the non-breeding period (92% ± 1%) than during breeding (40% ± 9%), revealing a cost of reproduction and suggesting a trade-off between surviving and reproducing. The low annual survival observed (34%) did not corroborate the pattern of high rates expected for a tropical bird. The largest population size was estimated to be 56 individuals in Nov/11, explained by high recruitment of juveniles, while the lowest observed in May/12: 10 individuals, probably as a result of massive influx of competitor species. Results from this study add to the growing literature on life history of Neotropical species. We encourage studies like this especially in Brazil, where there are few information, and suggest that covariates related to habitat quality and environmental changes should be tested, so that we can generate increasingly reliable models

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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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Foram realizados três experimentos para determinação das exigências de metionina+cistina (met+cis) digestível para aves da linhagem ISA Label. As aves foram criadas em semiconfinamento nas fases inicial (1 a 28 dias), crescimento (28 a 56 dias) e final (56 a 84 dias). em cada experimento, foram utilizadas 480 aves (metade de cada sexo) alojadas em 24 piquetes. O delineamento experimental utilizado foi o inteiramente casualizado, em esquema fatorial 4 × 2 (níveis de met+cis e sexos) com três repetições de 20 aves. Os níveis de met+cis digestível avaliados foram: 0,532; 0,652; 0,772; 0,892% na fase inicial; 0,515; 0,635; 0,755; 0,875% na fase de crescimento; e 0,469; 0,589; 0,709; 0,829% na fase final. Foram avaliados o desempenho, as características de carcaça, a deposição de proteína e gordura corporal, o peso e o teor de proteína das penas. Na fase inicial, os níveis de met+cis digestível na ração recomendados para machos e fêmeas foram 0,76 e 0,80%, que correspondem a 0,252 e 0,268% de met+cis por Mcal de energia metabolizável da ração, respectivamente. Para aves ISA Label na fase de crescimento, recomenda-se 0,716% de met+cis digestível na ração, independentemente do sexo, que corresponde a 0,235% de met+cis por Mcal de em da ração. Na fase final, recomendam-se níveis de met+cis digestível de 0,756 e 0,597%, que correspondem a 0,244 e 0,193% de met+cis por Mcal de energia metabolizável na ração para machos e fêmeas, respectivamente.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Foram realizados três experimentos para determinar as exigências de lisina digestível para aves da linhagem ISA Label, de ambos os sexos, criadas em semiconfinamento durante as fases: inicial (1 a 28 dias), de crescimento (28 a 56 dias) e final (56 a 84 dias). em cada experimento, foram utilizadas 480 aves, alojadas em 24 piquetes, cada um contendo abrigo coberto de 3,13m² e área de pastejo de 72,87m². O delineamento experimental utilizado foi o inteiramente ao acaso, em esquema fatorial 4x2 (níveis de lisina e sexo) com três repetições de 20 aves cada. Os níveis de lisina digestível avaliados foram: 0,850; 0,970; 1,090 e 1,210% na fase inicial; 0,750; 0,870; 0,990 e 1,110% na fase de crescimento e 0,640; 0,760; 0,880 e 1,000% na fase final. Foram mensuradas as variáveis de desempenho, característica de carcaça, deposição de proteína e gordura corporal, peso e teor de proteína das penas. Com base nos resultados de desempenho, recomendam-se 1, 041; 1,006 e 0,760% de lisina digestível em rações para aves ISA Label nas fases inicial, de crescimento e final, respectivamente.

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Um experimento foi conduzido para determinação dos valores de energia metabolizável aparente (EMA) e energia metabolizável aparente corrigida pelo balanço de nitrogênio (EMAn) e da composição química dos fenos de feijão-bravo (FFB), jureminha (FJ) e maniçoba (FM) para uso na alimentação de aves. Duzentos e oitenta pintos com 17 dias de idade foram distribuídos aleatoriamente em sete tratamentos, em esquema fatorial 3 x 2 + 1 (três tipos de feno x dois níveis de substituição da dieta-referência + dieta-referência), com quatro repetições de dez aves. Os níveis de EMA e EMAn dos fenos de jureminha, feijão-bravo e maniçoba foram 3.205 e 2.911, 2.990 e 2.648, 2.728 e 2.419, determinados com 15% de substituição da dieta-referência pelo alimento e 2.678 e 2.371, 2.875 e 2.523, 2.277 e 1.956 com substituição de 30%, respectivamente, e evidenciaram influência do nível de substituição da dieta-referência sobre os valores de EMA e EMAn das dietas. Os valores de EMA e EMAn, para aves, dos fenos de jureminha e feijão-bravo são superiores aos do feno de maniçoba.