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Search Results: 1 - 10 of 87168 matches for " Ant?nio Olinto ávila-da-Silva "
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Feeding ecology of a stream fish assemblage in an Atlantic Forest remnant (Serra do Japi, SP, Brazil)
Rolla, Ana Paula Pozzo Rios;Esteves, Katharina Eichbaum;ávila-da-Silva, Antnio Olinto;
Neotropical Ichthyology , 2009, DOI: 10.1590/S1679-62252009000100009
Abstract: this study aimed to characterize the trophic structure of the fish assemblage in streams of the serra japi, an ecotonal area between the atlantic forest and inland forests of s?o paulo state, southeastern brazil. fish were collected with electrofishing equipment in 15 sites covering different regions, substrate types and riparian vegetation, distributed throughout the cagua?ú river, caxambú, piraí and guapeva river micro-basins, during the rainy (january/february) and dry season (june) of 2007. the 589 specimens analyzed from 22 species, were assigned to different trophic groups, discriminated through a matrix of similarity, based on the food index (iai). the results show the formation of seven groups with a predominance of insectivorous and omnivorous species, followed by detritivores, piscivores, omnivore-carnivores and herbivores, which consumed mostly items of autochthonous origin, where algae and young insects were dominant. canonical correspondence analysis (cca), correlating the biomass of trophic groups to environmental variables, showed that omnivores, insectivores and omnivore-carnivores displayed a wide distribution, while detritivores, herbivores and piscivores were restricted to specific locations, related to different physical and chemical variables as total nitrogen, conductivity and temperature. despite the increase in total biomass at the most urbanized sites, the results indicate that the streams maintain a diverse community, suggesting that most of them are in preserved conditions.
Impacto do sistema pesqueiro multifrota sobre o estoque do peixe-porco (Balistes capriscus) capturado no Estado de S o Paulo =Assessment of a multi-fleet fishery for gray triggerfish (Balistes capriscus) in S o Paulo State
Marcelo Ricardo de Souza,Antnio Olinto ávila-da-Silva
Acta Scientiarum : Biological Sciences , 2010,
Abstract: O peixe-porco (Balistes capriscus) é um importante recurso pesqueiro no Estado de S o Paulo. Para se avaliar sua captura foram analisados dados de 15.004 espécimes provenientes de 91 desembarques das frotas de arrasto duplo de portas médio, arrasto de parelha e cerco, realizados no período de abr./1997 a dez./2000. Também foram consideradas informa es sobre a regulamenta o da pesca e o ciclo de vida desta espécie. A análise do direcionamento revelou que a espécie é capturada como fauna-acompanhante. A taxa de mortalidade total (Z) obtida para a espécie foi de 1,04 ± 0,3 ano-1, considerando-se todas as frotas e os desembarques totais para a espécie. O menor comprimento de primeira captura foi calculado para o arrasto duplo de portas médio (232 mm) e o maior, para o cerco (235 mm). Considerando-se o comprimento de primeira matura o (200 mm para machos e 169 mm para fêmeas) e as estimativas de seletividade, mortalidade e taxa de explota o, as frotas analisadas pescam principalmente indivíduos maduros e a espécie apresenta condi es favoráveis de explota o. Entretanto, deve-se considerar que, com a escassez de recursos tradicionais e a capacidade das frotas em direcionar suas capturas a espécies acessórias, é recomendado o acompanhamento constante da atividade pesqueira sobre o estoque de peixe-porco. The gray triggerfish (Balistes capriscus) is an important fisheries resource in S o Paulo State, southeastern Brazil. In this study, fisheries production and length distribution data per fleet were analyzed to assess the impact of a multi-fleet fishery system on its stock. The analysis was based on data taken from double rig otter trawl, purse seine and pair-trawl fleets, from April 1997 to December 2000. The effectiveness of fisheries regulation strategies and life history traits were also considered. Target effort analysis showed that gray triggerfish was a by-catch for most fishing fleets. The total mortality rate (Z), calculated considering the total catch, was 1.04 ± 0.3 year-1. Selectivity curves indicated the lowest length of first capture for double rig otter trawl (232 mm) and the highest for purse seine (235 mm). Selectivity curves, mortality and exploitation rates suggested that exploitation of gray triggerfish stock should be at a sustainable level. However, considering the scarcity of traditional resources and the ability of fishing fleets in direct their catches, the continued monitoring of the catch and effort data for this species is recommended.
Estabilidade temporal do conteúdo de água em três condi??es de uso do solo, em uma bacia hidrográfica da regi?o da Serra da Mantiqueira, MG
ávila, Léo Fernandes;Mello, Carlos Rogério de;Silva, Antnio Marciano da;
Revista Brasileira de Ciência do Solo , 2010, DOI: 10.1590/S0100-06832010000600024
Abstract: the description of soil hydrological processes is relatively complex, especially in the case of moisture, which is influenced by edaphic, topographic, climatic and vegetation factors. under field conditions, an adequate sampling strategy is required to estimate soil moisture, considering variations in time and space. to represent the soil moisture adequately with less sampling effort and cost, the concept of temporal stability has often been applied. this study was carried out with the objective of analyzing the temporal stability of the surface soil moisture (0-0.20 m layer) under three land uses in an experimental area in a catchment of the mantiqueira range region, state of minas gerais, brazil, in the dry and rainy seasons, identifying the most representative points for monitoring. greatest temporal stability was observed in the wetland, less under atlantic forest and intermediate in a pasture area. significant variation was also observed in the mean relative difference between the sampling periods, indicating that the characteristics of each site should be particularly considered to choose the points. in the pasture area, only one point could be identified to monitor both periods (rainy and dry). on the other hand, in the atlantic forest and wetland areas two points were identified, one specifically for the rainy and the other for the dry season; so an individual analysis for each season is recommended.
Continuidade e distribui??o espacial da umidade do solo em bacia hidrográfica da Serra da Mantiqueira
ávila, Léo F.;Mello, Carlos R. de;Silva, Antnio M. da;
Revista Brasileira de Engenharia Agrícola e Ambiental , 2010, DOI: 10.1590/S1415-43662010001200002
Abstract: the knowledge related to the spatial continuity of the soil moisture is essential for understanding and prediction of the hydrological processes. the geostatistical methodology has often been applied in such studies. in this context, the semi-variogram is used to model the spatial continuity of a specific variable for its mapping. this work aimed to model the spatial continuity of soil moisture in an experimental watershed located in mantiqueira range, mg, and then to generate map of soil moisture through the year. exponential, spherical and gaussian semi-variogram models were fitted applying the ordinary least square, weighted minimum square and maximum likelihood methodologies, testing their adherence based on the spatial dependence degree and database from cross-validation procedure. the exponential model presented better performance in 59% of the situations. the mean spatial dependence degree was 88%, showing a strong dependence degree to the spatial continuity structure. the soil moisture mapping demonstrated behavior strongly associated to the land use and topographical conditions.
Utiliza o do composto exaurido de Pleurotus sajor caju em ra es de frangos de corte e seus efeitos no desempenho dessas aves = Utilization of the spent substrate of Pleurotus sajor caju mushroom in broiler chicks ration and the effect on broiler chicken performance
Raquel Santos Azevedo,Carla Luiza da Silva ávila,Eustáquio Souza Dias,Antnio Gilberto Bertechini
Acta Scientiarum : Animal Sciences , 2009,
Abstract: Avaliou-se a adi o dietética de um composto exaurido da produ o docogumelo Pleurotus sajor caju sobre o desempenho de frangos de corte nos períodos de um a 21, 22 a 38 e um a 38 dias de idade. Foram utilizados 500 pintos de um dia Ross-308, machos, em delineamento inteiramente casualizado, com cinco tratamentos, obtidos pelosníveis do composto na ra o (0; 0,5; 1,0; 1,5 e 2,0%) com quatro repeti es de 20 aves cada. Foram avaliados ganho de peso, consumo de ra o, convers o alimentar, rendimento de carca a, gordura abdominal e altura das microvilosidades do intestino. A adi o do composto n o influenciou no consumo da ra o e na convers o alimentar. Para o ganho de peso houve efeito positivo somente na fase inicial (um a 21 dias), sendo o valor máximo obtido com a adi o de 0,67% do composto. A adi o do composto n o alterou o rendimento de carca a e gordura abdominal, porém, alterou a altura das microvilosidades do intestino. A adi o de composto exaurido da produ o do fungo Pleurotus sajor caju, na concentra o de 0,67%, melhora o ganho de peso dos frangos nos primeiros 21 dias de idade. This research evaluated the effect of the addition of a spent mushroom substrate (SMS) Pleurotus sajor caju at different levels on the performance of broiler chicks from 1 to 21, 22 to 38 and 1 to 38days of age. Five hundred one-day-old Ross-308 chicks were utilized, allocated in a completely randomized design, with five treatments obtained by increased levels of compost on ration (0; 0.5; 1.0; 1.5 and 2.0%), with four replicates of 20 birds per experimental unit. The intake, weight gain, feed conversion, carcass yield, abdominal fatand villus height were evaluated. No effect was observed on intake and feed conversion when the compost was included in the feeding. A positive effect was observed for weight gain from 1 to 21 days of age, with maximum value of 0.67% of SMS, but its addition didnot modify the carcass yield and abdominal fat, but modified the villus height. The inclusion of the spent substrate of Pleurotus sajor caju mushroom up to 0.67% improves the weight gain of broiler chicks in the first 21 days of age.
Padr?o espa?o-temporal da umidade volumétrica do solo em uma bacia hidrográfica com predominancia de latossolos
ávila, Léo Fernandes;Mello, Carlos Rogério de;Mello, José Márcio de;Silva, Antnio Marciano da;
Revista Brasileira de Ciência do Solo , 2011, DOI: 10.1590/S0100-06832011000500034
Abstract: the spatial and temporal variability of soil moisture is high due to the influence of several environmental features and the land-use. the understanding of this variability plays a fundamental role in the modeling of surface runoff, soil erosion and sediment transport. this study aimed to evaluate the spatial and temporal patterns of surface soil moisture over the annual seasons, in a watershed with predominance of oxisols in the south of the state of minas gerais. for this purpose, the temporal stability concept was used as well as semivariogram models to compare the spatial structure of the adjusted semivariogram models. it was possible to detect a strong spatial dependence of soil moisture in the watershed, with a spatial dependence degree of > 80 %. besides, spatial pattern of the scaled semivariograms was similar for summer and fall, and different for winter and spring. based on these results, the spatial patterns of soil moisture differed over the year, and were most homogenous in the rainy season (summer). differences in the temporal patterns of soil moisture according to the season were verified, and also, the sperman test demonstrated a temporal bias in soil moisture i winter and spring.
Distribui??o espacial de valores prováveis de precipita??o pluvial para períodos quinzenais, em Guiné-Bissau
Danfá, Sadjo;Silva, Antnio M. da;Mello, Carlos R. de;Coelho, Gilberto;Viola, Marcelo R.;ávila, Léo F.;
Revista Brasileira de Engenharia Agrícola e Ambiental , 2011, DOI: 10.1590/S1415-43662011000100010
Abstract: the aim of this study was to estimate the probable values of rainfall in the first and second halves of the months and its spatial distribution in guinea-bissau. distribution functions log-normal 2 parameters were used to estimate the probable values of rainfall adopting the probability level of 75%. the spatial interpolation (kriging) was applied by semi-variogram modeling demonstrating that the probable rainfall estimates have high spatial variability, except in the month of september, when the behavior is homogeneous for both first and second halves. the lowest probable values of rainfalls under 50 mm occur in june and october throughout the country, supporting the use of supplemental irrigation to avoid compromising the periods of sowing (june) and minimize damage at harvest (october, november) for long cycle crops.
Efeitos da compacta??o, da inclus?o de aditivo absorvente e do emurchecimento na composi??o bromatológica de silagens de capim-tanzania
Tavares, Valdir Botega;Pinto, José Cardoso;Evangelista, Antnio Ricardo;Figueiredo, Henrique César Pereira;ávila, Carla Luiza da Silva;
Revista Brasileira de Zootecnia , 2009, DOI: 10.1590/S1516-35982009000100006
Abstract: the objective of this work was to evaluate the effects of different compaction degrees, inclusion of absorbent additive and wilting on the chemical composition of tanzania grass silages. the experiment was conducted using tanzania grass (panicum maximum jacq. cv. tanzania i) harvested at 60-65 days of growth. the forage was ensiled in experimental pvc silos fitted with bunsen type valves, with capacity for about 4 and 8 kg each. the treatments consisted of three types of silages (control, 5% of citric pulp and pre-wilted) with five compaction degrees (400, 500, 600, 700 and 900 kg/m3). the experimental design was random blocks, with four replicates. citric pulp and pre-wilting increased the dry matter content of tanzania grass silages. the increased density resulted into decreases in the ph values and amoniacal-n contents; the greatest densities resulted in ph values within the ideal range. the presence of citric pulp and the pre-wilting practice reduce the losses by effluent and gas relative to the control. as the density increased, the amount of effluent increased in the control silage and decreased in silages with citric pulp.
Perfil de fermenta??o das silagens de capim-tanzania com aditivos teores de nitrogênio amoniacal e ph
ávila, Carla Luiza da Silva;Pinto, José Cardoso;Evangelista, Antnio Ricardo;Morais, Augusto Ramalho de;Figueiredo, Henrique Cesar Pereira;Tavares, Valdir Botega;
Ciência e Agrotecnologia , 2003, DOI: 10.1590/S1413-70542003000500024
Abstract: in general, forage grasses harvested at younger development stage present low contents of dm that associated to the low content of soluble carbohydrates, can harm the fermentation harming the final quality of the silage. thus, it is indispensable to adopt procedures which modify this picture such as the use of additives. this work aimed to evaluate the fermentation of tanzania grass silages with additives in relation to the ammonia-n content and ph, and among these additives, to determine which of them and what dose confers the best qualities to the produced silage. the experiment was carried out in the animal science department of ufla by utilizing tanzaniagrass (panicum maxium jacq. cv. tanzania i) established in a clayey dusky red latosol and harvested at 60-65 days of growth. the forage was ensiled in experimental pvc silos, adapted with valves type bunsen with capacity of about 3 kg each. the treatments consisted of three additives (citrus pulp, wheat meal and corn meal) in four doses (3, 6, 9 and 12%) plus one without additives and 8 times of silo opening (0, 1, 2, 3, 7, 14, 28 and 56 days). the experimental design utilized was randomized blocks, constituing a factorial scheme with additional treatment [(3x4) + 1] x 8 with 3 replicates. the addition of citrus pulp, wheat meal and corn meal improves the fermentative characteristics of the tanzaniagrass silage. the silages without additives present values of ph and ammonia-n characteristics of a satisfactory quality silage but the use of additives is recommended to prevent losses.
Metodologias de avalia??o do valor nutricional do farelo de arroz desengordurado para suínos
Kunrath, Marco Antnio;Kessler, Alexandre de Mello;Ribeiro, Andréa Machado Leal;Vieira, Maitê de Moraes;Silva, Gabriel Luz da;Peixoto, Felipe D'ávila;
Pesquisa Agropecuária Brasileira , 2010, DOI: 10.1590/S0100-204X2010001000017
Abstract: the objective of this work was to compare the substitution method and the regression analysis method to determine the nutritional value of defatted rice bran in diets for swines at growing and finishing phases. two digestibility bioassays were carried out with 16 barrows with initial body weight of 50.0±3.1 kg, in the growing phase, and 16 barrows with initial body weight of 95.0±3.8 kg, in the finishing phase, housed in metabolic cages. a completely randomized design was used with four treatments - 0, 15, 30 and 45% of substitution of the reference diet by defatted rice bran - and four replications, with one animal as the experimental unit. the regression analysis was more accurate than the method of substitution to assess the nutritional value of defatted rice bran. throught this analyse, the apparent digestibility coefficients of dry matter, organic matter, crude protein and metabolizable energy of defatted rice bran were, respectively, 57.7, 64.8, 56.6% and 2,429 kcal kg-1 on growing phase, and 57.7, 64.7, 62.6% and 2,233 kcal kg-1 on finishing phase.
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