874 resultados para Fishes - Feeding and feeds


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To elucidate the role of neuropeptide Y (NPY)-Y1 receptor (Y1-R) in food intake, energy expenditure, and other possible functions, we have generated Y1-R-deficient mice (Y1-R−/−) by gene targeting. Contrary to our hypothesis that the lack of NPY signaling via Y1-R would result in impaired feeding and weight loss, Y1-R−/− mice showed a moderate obesity and mild hyperinsulinemia without hyperphagia. Although there was some variation between males and females, typical characteristics of Y1-R−/− mice include: greater body weight (females more than males), an increase in the weight of white adipose tissue (WAT) (approximately 4-fold in females), an elevated basal level of plasma insulin (approximately 2-fold), impaired insulin secretion in response to glucose administration, and a significant changes in mitochondrial uncoupling protein (UCP) gene expression (up-regulation of UCP1 in brown adipose tissue and down-regulation of UCP2 in WAT). These results suggest either that the Y1-R in the hypothalamus is not a key molecule in the leptin/NPY pathway, which controls feeding behavior, or that its deficiency is compensated by other receptors, such as NPY-Y5 receptor. We believe that the mild obesity found in Y1-R−/− mice (especially females) was caused by the impaired control of insulin secretion and/or low energy expenditure, including the lowered expression of UCP2 in WAT. This model will be useful for studying the mechanism of mild obesity and abnormal insulin metabolism in noninsulin-dependent diabetes mellitus.

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This paper provides data on diet and feeding habits of five benthic fish species (Torpedo torpedo (Linnaeus,1758), Mullus surmuletus (Linnaeus, 1758), Uranoscopus scaber (Linnaeus,1758), Scorpaena scrofa (Linnaeus,1758) and Synaptura lusitanica (Capello,1868)) common in the artisanal fisheries in the Cullera coast (Mediterranean sea – Spain) and T.torpedo, U.scaber y S. lusitánica feeding habits are almost unknown. T. torpedo preferred small preys like fishes, polychaetes and molluscs, these preys were feed in small portions. M. surmuletus showed the highest feeding dynamic, consuming small prey in large numbers like crustaceans (brachyura and amphypoda). U. scaber had similar feeding habits, but the numbers of preys in the stomach were lower. The principal preys were fishes, crustaceans, molluscs and polychaetes. S.scrofa ate larger prey items such as fish, followed by crustaceans and molluscs. Finally S. lusitánica had a high vacuity index, feeding polychaetes as the most important prey in their diet. Feeding strategy indicates a specialization of T.torpedo, S.scrofa and S. lusitanica; conversely M. surmuletus and U. scaber were generalized species.

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Mode of access: Internet.

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Report year ends September 30.

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Background: To investigate the association between selected social and behavioural (infant feeding and preventive dental practices) variables and the presence of early childhood caries in preschool children within the north Brisbane region. Methods: A cross sectional sample of 2515 children aged four to five years were examined in a preschool setting using prevalence (percentage with caries) and severity (dmft) indices. A self-administered questionnaire obtained information regarding selected social and behavioural variables. The data were modelled using multiple logistic regression analysis at the 5 per cent level of significance. Results: The final explanatory model for caries presence in four to five year old children included the variables breast feeding from three to six months of age (OR=0.7, CI=0.5, 1.0), sleeping with the bottle (OR=1.9, CI=1.5, 2.4), sipping from the bottle (OR=1.6, CI=1.2, 2.0), ethnicity other than Caucasian (OR=1.9, CI=1.4, 2.5), annual family income $20,000-$35,000 (OR = 1.7, CI=1.3, 2.3) and annual family income less than $20,000 (OR=2.1, CI=1.5, 2.8). Conclusion: A statistical model for early childhood caries in preschool children within the north Brisbane region has been constructed using selected social and behavioural determinants. Epidemiological data can be used for improved public oral health service planning and resource allocation within the region.

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A two-factor no-arbitrage model is used to provide a theoretical link between stock and bond market volatility. While this model suggests that short-term interest rate volatility may, at least in part, drive both stock and bond market volatility, the empirical evidence suggests that past bond market volatility affects both markets and feeds back into short-term yield volatility. The empirical modelling goes on to examine the (time-varying) correlation structure between volatility in the stock and bond markets and finds that the sign of this correlation has reversed over the last 20 years. This has important implications far portfolio selection in financial markets. © 2005 Elsevier B.V. All rights reserved.

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Feeding behaviour of trained rainbow trout was investigated by the use of demand feeders, under different light conditions. The effects of the energy content of diet, and the size, colour and texture of feed pellets, on the feeding behaviour, were studied. An attempt was made to locate the assumed centres for feeding and satiety in the hypothalamus of brain by the intraperitoneal injections of goldthioglucose. Feeding under nine different constant photoperiods at 160 lux, at a temperature of 13.5°C, showed that trout exhibit a rhythmic pattern of feeding behaviour in all photoperiods except in continuous darkness.Feeding rhythms of trout attributable to the degree of gut distension were formed every eight to ten hours. Further studies by varying levels of light intensity revealed the interaction of light intensity and photoperiod. At shorter photoperiods lower levels of light intensity decreased the feeding activity in terms of food intake but by increasing the photoperiod the same feeding activity was accomplished as by the fish subject to a short photoperiod but under higher light intensity.Simulated effect of increasing and decreasing daylengths did not affect the overall food intake and growth performance. Trout are quite efficient in adjusting their food intake in terms of energy content. Colour, size and texture of feed pellets affect the feeding responses and elicit preferential food selection behaviour in trout. Goldthioglucose induced some reversable toxic effects upon general physiology of trout and did not produce any lesions in the assumed areas of feeding and satiety centres in the brain.  It was concluded that the feeding behaviour of trout exhibited selective preferences according to the physical nature of food items and those preferences could be further influenced by the biotic and abiotic factors, light being one of the most important abiotic factors.

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Lithofacies distribution indicates that the Much Wenlock Limestone Formation of England and South Wales was desposited on a shelf which was flat and gently subsiding in the north, but topographically variable in the south. Limestone deposition in the north began with 12m of alga-rich limestone, which formed an upward shoaling sequence. Deepening then led to deposition of calcareous silty mudstones on the northern shelf. The remainder of the formation in this area formed during a shelf-wide regression, culminating in the production of an E to W younging sandbody. Lithofacies distribution on the southern shelf was primarily controlled by local subsidence. Six bedded lithofacies are recognised which contain 14 brachiopod/bryozoan dominated assemblages, of which 11 are in situ and three consist of reworked fossils. Microfacies analysis is necessary to distinguish assemblages which reflect original communities from those which reflect sedimentary processes. Turbulence, substrate-type, ease of feeding and other organisms in the environment controlled faunal distribution. Reefs were built dominantly by corals, stromatoporoids, algae and crinoids. Coral/stromatoporoid (Type A) reefs are common, particularly on the northern shelf, where they formed in response to shallowing, ultimately growing in front of the advancing carbonate sandbody. Algae dominate Type B and Type C reefs, reflecting growth in areas of poor water circulation. Lithification of the formation began in the marine-phreatic environment with precipitation of aragonite and high Mg calcite, which was subsequently altered to turbid low Mg calcite. Younger clear spars post-date secondary void formation. The pre-compactional clear spars have features which resemble the products of meteoric water diagenesis, but freshwater did not enter the formation at this time. The pre-compactional spars were precipitated by waters forced from the surrounding silty mudstones at shallow burial depths. Late diagenetic products are stylolites, compaction fractures and burial cements.

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BACKGROUND: Retinal vessel oxygenation saturation measurements have been the focus of much attention in recent years as a potential diagnostic parameter in a number of ocular and systemic pathologies. This interest has been heightened by the ability to measure oxygen saturation in vivo using a photographic technique. METHODS: Retinal vessel oxygenation in venules and arterioles of 279 retinal vessels of 12 healthy Caucasian participants (mean age: 30 SD (+/- 6) years) were measured consecutively three times to evaluate short-term variation in oxygen saturation and regional variability of retinal vessel oxygen saturation using dual-wavelength technology (Oxymetry Modul, Imedos, Germany). All subjects underwent standard optometric assessment including non-contact intra-ocular pressure assessment as well as having their systemic blood pressure measured. RESULTS: Vessels were grouped as either near-macula or peripheral, depending on their location. Peripheral arterioles and venules exhibited significantly lower oxygen saturation compared to their near-macula counterparts (arterioles: 94.7% (SD 3.9) vs. 99.7% (SD 3.2); venules: 65.1% (SD 7.2) vs. 90.3% (SD 6.7)). Both arterioles and venules, main branches, and those feeding and draining the retina near the macula and periphery showed low short-term variability of oxygen saturation (arterioles: COV 1.2-1.8%; venules: COV 2.9-4.9%). CONCLUSIONS: Retinal arterioles and venules exhibit low short-term variation of oxygen saturation in healthy subjects. Regional differences in oxygen saturation could be a potential useful marker for risk stratification and diagnostic purposes of area-specific retinal pathology such as age-related macula degeneration and diabetic maculopathy.

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Parental reports suggest that difficulties related to child-feeding and children's eating behaviour are extremely common. While 'fussy eating' does not pose an immediate threat to health, over the long-term, consumption of a poor diet can contribute to the development of a range of otherwise preventable diseases. In addition, the stress and anxiety that can surround difficult mealtimes can have a detrimental impact upon both child and parental psychological wellbeing. Since parents have a great influence over what, when, and how much food is offered, feeding difficulties may be preventable by better parental awareness. The aim of this review is to describe how parental factors contribute to the development of common feeding problems, and to discuss the merits of existing interventions aimed at parents/primary caregivers to improve child-feeding and children's eating behaviour. The potential for different technologies to be harnessed in order to deliver interventions in new ways will also be discussed. © 2012 Elsevier Ltd.

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Objective: To investigate the relationship between maternal psychopathological symptomatology during pregnancy and at 6 and 12 months postnatally and maternal use of controlling and restrictive feeding practices at 1 year. Research Methods and Procedures: Eighty-seven women completed a measure of psychological distress during pregnancy and at 6 and 12 months postpartum, and at 12 months postnatally these women reported their usage of controlling and restrictive feeding practices and were observed feeding their infants. Results: General psychological distress, particularly anxious psychopathology, during pregnancy and at 6 and 12 months postnatally was significantly associated with maternal use of restrictive feeding practices at 1 year, even when controlling for length of breast-feeding and the infants' weights at 1 year. Contrary to expectations, depression and eating psychopathology as measured by the SCOFF eating disorder measure during pregnancy or at 6 or 12 months postnatally were not associated with the use of controlling or restrictive feeding practices at 1 year. Discussion: These findings indicate that anxious maternal psychopathology may partially explain the development of maternal use of restriction when feeding. Copyright © 2005 NAASO.

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This study evaluates the antidiabetic potential of an enzyme-resistant analog, (Val8)GLP-1. The effects of daily administration of a novel dipeptidyl peptidase IV-resistant glucagon-like peptide-1 (GLP-1) analog, (Val8)GLP-1, on glucose tolerance and pancreatic β-cell function were examined in obese-diabetic (ob/ob) mice. Acute intraperitoneal administration of (Val8)GLP-1 (6.25-25 nmol/kg) with glucose increased the insulin response and reduced the glycemic excursion in a dose-dependent manner. The effects of (Val8)GLP-1 were greater and longer lasting than native GLP-1. Once-daily subcutaneous administration of (Val8)GLP-1 (25 nmol/kg) for 21 days reduced plasma glucose concentrations, increased plasma insulin, and reduced body weight more than native GLP-1 without a significant change in daily food intake. Furthermore, (Val8)GLP-1 improved glucose tolerance, reduced the glycemic excursion after feeding, increased the plasma insulin response to glucose and feeding, and improved insulin sensitivity. These effects were consistently greater with (Val8)GLP-1 than with native GLP-1, and both peptides retained or increased their acute efficacy compared with initial administration. (Val8)GLP-1 treatment increased average islet area 1.2-fold without changing the number of islets, resulting in an increased number of larger islets. These data demonstrate that (Val8)GLP-1 is more effective and longer acting than native GLP-1 in obese-diabetic ob/ob mice.

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The metabolic rate of organisms may either be viewed as a basic property from which other vital rates and many ecological patterns emerge and that follows a universal allometric mass scaling law; or it may be considered a property of the organism that emerges as a result of the organism's adaptation to the environment, with consequently less universal mass scaling properties. Data on body mass, maximum ingestion and clearance rates, respiration rates and maximum growth rates of animals living in the ocean epipelagic were compiled from the literature, mainly from original papers but also from previous compilations by other authors. Data were read from tables or digitized from graphs. Only measurements made on individuals of know size, or groups of individuals of similar and known size were included. We show that clearance and respiration rates have life-form-dependent allometries that have similar scaling but different elevations, such that the mass-specific rates converge on a rather narrow size-independent range. In contrast, ingestion and growth rates follow a near-universal taxa-independent ~3/4 mass scaling power law. We argue that the declining mass-specific clearance rates with size within taxa is related to the inherent decrease in feeding efficiency of any particular feeding mode. The transitions between feeding mode and simultaneous transitions in clearance and respiration rates may then represent adaptations to the food environment and be the result of the optimization of tradeoffs that allow sufficient feeding and growth rates to balance mortality.