895 resultados para Opportunistic feeding
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We studied the diet of Liophis reginae semilineatus (Wagler, 1824) from eastern Amazon, Brazil, based on the analysis of 182 preserved specimens. Thirty-six individuals had prey in their stomachs; 34 (95%) contained exclusively anurans and 2 (5%) contained both anurans and lizards. The most common prey items were small Leptodactylus sp. (33.3%), followed by Physalaemus ephippifer (Steindachner, 1864) (10.3%). Prey ingested head-first (78%; n = 25) were significantly larger than prey ingested tail-first (22%; n = 7). Females of L. reginae semilineatus have longer and wider heads than conspecific males with the same body length, which correspond to sexual divergences in the diet (size of the prey). No correlation was found between snake head length vs. prey size (SVL, width and mass). Liophis reginae semilineatus is an anurophagous snake that probably forages actively on the ground.
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Um método quantitativo para se estimar o consumo alimentar e o aporte energético das diferentes categorias alimentares é apresentado através da reconstrução das presas ingeridas com base em estruturas corporais não digeríveis. Para tal, o presente estudo estabelece, através do exame dos conteúdos estomacais de 1.086 exemplares dissecados de Macrodon ancylodon (Bloch & Schneider, 1801), Stellifer rastrifer (Jordan, 1889) e Stellifer naso (Jordan, 1889), as equações das relações funcionais entre o peso das presas e estruturas corporais. Com as categorias reconstruídas foi possível quantificar o alimento ingerido pelos espécimes. Os resultados indicaram que existe uma marcada diferença, tanto na composição das categorias alimentares, bem como no aporte energético acompanhando o desenvolvimento ontogênico do predador.
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A dieta e a ecologia alimentar de juvenis de Lutjanus jocu foram verificadas em 92 espécimes coletados em quatro canais de maré do estuário do rio Curuçá, Norte do Brasil, entre setembro de 2003 e julho de 2004. O comprimento total dos peixes coletados não apresentou diferenças significativas entre os meses amostrados. A intensidade alimentar foi elevada conforme indicado pelos altos valores do índice de repleção estomacal e os baixos valores do índice de vacuidade. A presa mais importante foi Penaeidae, seguida por Grapsidae e Porcellanidae. A dieta de juvenis de L. jocu apresentou diferenças sazonais evidentes. Os espécimes da estação seca (setembro e novembro) e transição seca/chuvosa (janeiro) foram considerados especialistas alimentando-se exclusivamente de Penaeidae. No entanto, os espécimes da estação chuvosa (março e maio) e da transição chuvosa/seca (julho), que alimentaram-se principalmente de Grapsidae, Penaeidae e Porcellanidae, foram considerados generalistas. Esta mudança sazonal na dieta poderia estar relacionada com a disponibilidade do alimento.
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O estudo da ecologia alimentar de peixes é uma abordagem consistente na avaliação dos processos interativos dentro das comunidades. Dessa forma, este trabalho teve como objetivo investigar a ecologia alimentar do bacu-pedra Lithodoras dorsalis em furos próximos no delta do estuário Amazônico (Brasil), uma área sobre influência de macro-marés, em diferentes períodos pluviométricos. Durante 12 meses de coletas (julho de 2010 a junho de 2011), foram coligidos 371 espécimes jovens, sendo que a dieta da espécie foi composta por 28 itens alimentares analisados pelos seguintes índices: Índice de Repleção Estomacal, Índice de Importância Alimentar e Amplitude de Nicho. Lithodoras dorsalis quando jovem foi classificada como herbívora com tendência à frugivoria, devido aos altos valores de importância de frutos e sementes em sua dieta. A intensidade de obtenção de alimento por L. dorsalis diferiu entre os meses de coleta, onde o final do período de transição chuva-estiagem e o início da estiagem foram os períodos de menor e maior atividade alimentar, respectivamente. Também houve diferença na importância alimentar dos itens entre os períodos pluviométricos. Estes resultados fornecem informações importantes sobre a ecologia alimentar de doradídeos na Amazônia. Além disso, percebeu-se o alto consumo de material alóctone pelo bacu-pedra, sendo estes itens alimentares provenientes da floresta ripária, o que reforça a importância deste ambiente para a conservação da ictiofauna neotropical.
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The objective of this work was to evaluate the performance of Pacific marine shrimp (Litopenaeus vannamei) and tilapia (Oreochromis niloticus), in a polyculture in tanks subjected to different stocking densities and feeding strategies, in comparison with monoculture. Two experiments were performed, at the same time, in a completely randomized design with three treatments and four replicates each. Treatments for experiment I were: monoculture with 10 shrimp per m² (10S:0T); polyculture with 10 shrimp and 0.5 tilapia per m² (10S:0.5T); and polyculture with 10 shrimp and 1 tilapia per m² (10S:1T). Shrimp was the main crop, and feed was provided based on shrimp biomass. Treatments for experiment II were: monoculture with 2 tilapia per m² (2T:0S); polyculture with 2 tilapia and 2.5 shrimp per m² (2T:2.5S); and polyculture with 2 tilapia and 5 shrimp per m² (2T:5S). Tilapia was the main crop, and feed was provided based on fish requirements. In the experiment I, tilapia introduction to shrimp culture resulted in lower shrimp growth and poor feed conversion rate. In experiment II, shrimp introduction to tilapia culture did not interfere with fish performance. Polyculture is more efficient with the combination of 2 tilapia and 2.5 or 5 shrimp per m² and feed based on fish requirements.
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The present study was conducted to evaluate the effects of feeding whole linseed on the laying performance and egg characteristics in laying hens kept at high ambient environmental temperatures (average 34 degrees C; the diurnal temperature range 26 degrees C to 41 degrees C). Two hundred and forty 38-wk-old white Leghorn laying hens were fed diets containing 0, 5, 10 or 15% whole linseed (as a source of n-3 polyunsaturated fatty acids) for a period of 12 weeks. Egg production was recorded daily, while feed intake and egg characteristics were monitored on weekly basis. The results of the study demonstrated that egg production and feed intake decreased, while feed conversion ratio (FCR) per dozen of eggs increased (p <= 0.05) with increasing dietary linseed levels. Egg weight, yolk weight, albumen height, eggshell weight, and eggshell thickness were not influenced (p > 0.05) by linseed levels in the diets offered to the laying hens. The results of the present trial suggest that feeding linseed to the laying hens in hot climates has no detrimental effects on egg characteristics, but has suppressive effects on egg production, feed intake and feed efficiency of laying hens.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Effect of honey feeding by thyrinteina arnobia males and females on their reproduction and longevity
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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
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Patients with neurological disorders have an increased risk of oral and systemic diseases due to compromised oral hygiene. If patients lose the ability to swallow and chew food as a result of their disorder, enteral nutrition is often utilized. However, this type of feeding may modify salivary antioxidant defenses, resulting in increased oxidative damage and the emergence of various diseases. The aim of this study was to evaluate the effects of enteral nutrition on biochemical parameters in the unstimulated whole saliva composition of patients with neurological disorders. For this, enzymatic (superoxide dismutase - SOD; glutathione peroxidase - GPx) and non-enzymatic (uric acid; ferric ion reducing antioxidant power - FRAP) antioxidant activity, as well as a marker for oxidative damage (thiobarbituric acid reactive substances - TBARS) were analyzed. Unstimulated whole saliva was collected from 12 patients with neurological disorders and tube-feeding (tube-fed group - TFG), 15 patients with neurological disorders and normal feeding via the mouth (non-tube-fed group - NTFG), and 12 volunteers without neurological disorders (control group - CG). The daily oral hygiene procedures of TFG and NTFG patients were similar and dental care was provided monthly by the same institution's dentist. All patients exhibited adequate oral health conditions. The salivary levels of FRAP, uric acid, SOD, GPx, TBARS, and total protein were compared between studied groups. FRAP was increased (p < 0.05) in the NTFG (4651 +/- 192.5 mmol/mL) and the TFG (4743 +/- 116.7 mmol/mL) when compared with the CG (1844 +/- 343.8 mmol/mL). GPx values were lower (p < 0.05) in the NTGF (8.24 +/- 1.09 mmol/min/mg) and the TFG (8.37 +/- 1.60 mmol/min/mg) than in the CG (15.30 +/- 2.61 mmol/min/mg). Uric acid in the TFG (1.57 +/- 0.23 mg/dL) was significantly lower than in the NTFG (2.34 +/- 0.20 mg/dL) and the CG (3.49 +/- 0.21 mg/dL). Protein was significantly lower in the TFG (5.35 +/- 0.27 g/dL) than in the NTFG (7.22 +/- 0.57 g/dL) and the CG (7.86 +/- 0.54 g/dL). There was no difference in the salivary flow rate and SOD between groups. Enteral nutrition in patients with neurological disorders was associated with lower oxidative damage, resulting in increased salivary. antioxidant capacity. These results emphasize the importance of oral care for this population to prevent oral and systemic diseases. (C) 2014 Elsevier Ltd. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The objective of this study was to evaluate the postweaning history of heifers kept on marandu grass pastures with three canopy heights, in a continuous-grazing system, during the rainy period, on feedlot-or pasture finishing. The effects of three canopy heights (15, 25 and 35 cm) associated with two supplements (mineral salt and protein-energy supplement) and two finishing systems in the dry period (feedlot and open pasture) were studied in the postweaning period during the rainy season. The adopted design was completely randomized, with seven replications (animals) in a 2 x 2 factorial arrangement. The animals which received protein-energy supplement reached the finishing period with greater body weight in relation to those fed mineral salt. In both feedlot and pasture finishing systems, compensatory gain effect was observed in the animals that remained on the low pastures during postweaning compared with the high pastures. This compensatory gain was not verified in the animals that received protein-energy supplement in relation to the mineral salt, and thus the animals were slaughtered beforehand. The heifers on pastures with 25 or 35 cm in height were slaughtered in the same period, and those kept on the low pastures were slaughtered afterwards. The studied factors in the postweaning phase did not affect the carcass characteristics. Animals finished in feedlot slaughtered with the same body weight as those finished on pasture show greater carcass yield, subcutaneous fat deposition and renal pelvic and inguinal fat and greater losses with trimmings for cleaning the main hindquarter meat cuts; however, they provide cuts with the same weight but greater fat cover.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The feeding behaviour and the swimming pattern of the reef manta (Manta alfredi) are described based on video recordings conducted in Sudan, Red Sea, Indian Ocean, during June 2001. Three circular swimming patterns are described: horizontal circle pattern, inclined circle pattern and double circle pattern, related to feedings on zooplankton distributed in the water column. The observation of circle-like swimming patterns for reef manta rays in shallow waters expands our knowledge about M. alfredi and suggests that the distribution and abundance of zooplankton influence the occurrence and group size of this species in the studied area, as reported from other localities for Manta species.
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Associations among feeding habit, beak type, and food source in birds have been widely studied and are well known to exist. The relationship between feeding habit and jaw apparatus in birds has not attracted attention from ornithologists, perhaps because of the complexity of the skeletal morphology of the feeding system of birds. The goal of this study was to compare the jaw apparatus and foraging strategies of various Oriental species of the Picidae (Meiglyptini and Picini tribes) using a morphofunctional analysis of the skeletal structure of the jaw apparatus. This study showed that there are at least three types of jaw apparatus in these woodpeckers, as follows: 1) robust, developed, and complex; 2) complexity and development intermediate, as observed in Meiglyptes tristis and Dinopium spp., whose main foraging method involves gleaning, probing, and tapping; and 3) poorly developed, as observed in Picus miniaceus and Hemicircus concretus. The success of woodpeckers as a natural group is due not only to their feeding diversity, but also their ability to explore a wide range of different resources, as appropriate to their jaw apparatus.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)