757 resultados para Diet and nutrition
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We describe a child bom to unrelated parents who developed severe protracted secretory type diarrhea associated with subtotal villus atrophy and intestinal inflammation at the age of 19 months. No infectious, metabolic, or anatomical basis for this condition was identified and the child required total parenteral nutrition for a period of 18 months despite trials of special enteral formulas, steroids, and anti-inflammatory agents. This refractory “enteropathy” responded dramatically to the introduction of cyclosporin, with cessation of the secretory diarrhea, recovery from the enteropathy, and cessation of parenteral nutrition. The symptoms relapsed when cyclosporin was briefly discontinued and improved following reintroduction of this drug. This experience suggests a role for immune factors in the pathogenesis of the enteropathy in this case and that a trial of cyclosporin is worthy of consideration in similar cases. © 1990 Raven Press, Ltd., New York.
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This paper summarise six studies undertaken by the Sheep CRC to elucidate certain aspects of confinement feeding of sheep. A review of confinement feeding highlighted the variability of growth rate and feed conversion of sheep and revealed that little is known about the use of sorghum for feeding sheep. The review indicated that the main factors responsible for variation of growth rate and feed conversion were adaptation to grain and feeding system, including the preparation and presentation of feed. The importance of social and physiological adaptation to grain feeding was confirmed. Factors identified as responsible for safe induction and uniform growth rates included prior exposure to grain as lambs, gradual introduction of grain and, when concentrate was provided ad libitum from the first day, the use of either virginiamycin, a pelleted feed, a total mixed ration or a step-wise increase of high-starch grain components. Separate feeding of hay and grain resulted in performance comparable with that of a pelleted diet and that of a total mixed ration. Sorghum-based concentrate diets resulted in growth rates and carcase weights similar to that for winter cereal grains or pellets. Steam flaking or expanding of sorghum had no significant effect on growth rates or carcase weights. These results can be used to determine the profitability of various feedlotting options.
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The demonstrated wide adaptability, substantial yield potential and proven timber quality of African mahogany (Khaya senegalensis) from plantings of the late 1960s and early 1970s in northern Australia have led to a resurgence of interest in this high-value species. New plantations or trials have been established in several regions since the early 1990s -in four regions in north Queensland, two in the Northern Territory and one in Western Australia. Overall, more than 1500 ha had been planted by early 2007, and the national annual planting from 2007-2008 as currently planned will exceed 2400 ha. Proceedings of two workshops have summarised information available on the species in northern Australia, and suggested research and development (R&D) needs and directions. After an unsustained first phase of domestication of K. senegalensis in the late 1960s to the early 1970s, a second phase began in northern Australia in 2001 focused on conservation and tree improvement that is expected to provide improved planting stock by 2010. Work on other aspects of domestication is also described in this paper: the current estate and plans for extension; site suitability, soils and nutrition; silviculture and management; productivity; pests and diseases; and log and wood properties of a sample of superior trees from two mature plantations of unselected material near Darwin. Some constraints on sustainable plantation development in all these fields are identified and R&D needs proposed. A sustained R&D effort will require a strategic coordinated approach, cooperative implementation and extra funding. Large gains in plantation profitability can be expected to flow from such inputs.
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We previously found high carotenoid levels in Karat and other Micronesian bananas, indicating potential importance for alleviating vitamin A deficiency and other nutritionally related health problems in the Federated States of Micronesia. Past work focused on carotenoid and mineral analyses, whereas here we investigated 16 cultivars (most not previously analysed) for a broader micronutrient profile, including seven vitamins. Karat carotenoid levels were higher than in previous analyses, confirming Karat as exceptionally carotenoid-rich. We identified an additional 10 carotenoid-rich cultivars, expanding the range having potential for alleviating vitamin A deficiency. A striking finding is the high riboflavin level in Karat, including high levels of uncharacterized flavonoids. Niacin and α-tocopherol are at levels that may contribute importantly to dietary intake within normal patterns of consumption. These data present a more complete basis for promoting the nutritional benefits of these banana cultivars where they are consumed in the Pacific, and potential benefits for promoting elsewhere.
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Background: The problems of vitamin A deficiency and chronic diseases have emerged in recent years in some countries in the Micronesian region. These problems are associated with the dietary shift towards imported processed foods and lifestyle changes. Research in the Federated States of Micronesia indicates that yellow- and orange-fleshed banana cultivars contain significant levels of provitamin A carotenoids. Objective: To identify further banana cultivars that may be promoted to alleviate vitamin A deficiency among children and women and chronic disease problems among adults. Methods: Ripe fruit of banana cultivars growing in Australia (sourced mostly from a field research collection) were assessed for carotenoid content and flesh color. Ten cultivars with yellow or yellow/orange flesh color (including common cultivars of Southeast Asia and the Pacific Islands) were selected and compared with two cream-fleshed cultivars, including Williams, of the Cavendish group, the most commonly marketed banana worldwide. Carotenoid content was analyzed by high-performance liquid chromatography (HPLC). Flesh color was analyzed by HunterLab colorimetry. Results: The yellow/orange-fleshed Asupina (a Fe'i banana) contained the highest level (1,412 μg/100 g) of trans β-carotene, the most important provitamin A carotenoid, a level more than 20 times higher than that of Williams. All 10 yellow or yellow/orange-fleshed cultivars (Asupina, Kirkirnan, Pisang Raja, Horn Plantain, Pacific Plantain, Kluai Khai Bonng, Wain, Red Dacca, Lakatan, and Sucrier) had significant carotenoid levels, potentially meeting half or all of the estimated vitamin A requirements for a nonpregnant, nonlactating adult woman within normal consumption patterns. All were acceptable for taste and other attributes. The cream-fleshed cultivars had minimal carotenoid levels. There was a positive significant correlation between carotenoid content and deeper yellow/orange coloration indicators. Conclusions: These yellow- or yellow/orange-fleshed carotenoid-rich banana cultivars should be considered for promotion in order to alleviate vitamin A deficiency and chronic disease in susceptible target communities and to provide variety and enjoyment as exotic fruits in both developing and industrialized countries.
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Grass (monocots) and non-grass (dicots) proportions in ruminant diets are important nutritionally because the non-grasses are usually higher in nutritive value, particularly protein, than the grasses, especially in tropical pastures. For ruminants grazing tropical pastures where the grasses are C-4 species and most non-grasses are C-3 species, the ratio of C-13/C-12 in diet and faeces, measured as delta C-13 parts per thousand, is proportional to dietary non-grass%. This paper describes the development of a faecal near infrared (NIR) spectroscopy calibration equation for predicting faecal delta C-13 from which dietary grass and non-grass proportions can be calculated. Calibration development used cattle faeces derived from diets containing only C-3 non-grass and C-4 grass components, and a series of expansion and validation steps was employed to develop robustness and predictive reliability. The final calibration equation contained 1637 samples and faecal delta C-13 range (parts per thousand) of [12.27]-[27.65]. Calibration statistics were: standard error of calibration (SEC) of 0.78, standard error of cross-validation (SECV) of 0.80, standard deviation (SD) of reference values of 3.11 and R-2 of 0.94. Validation statistics for the final calibration equation applied to 60 samples were: standard error of prediction (SEP) of 0.87, bias of -0.15, R-2 of 0.92 and RPD of 3.16. The calibration equation was also tested on faeces from diets containing C-4 non-grass species or temperate C-3 grass species. Faecal delta C-13 predictions indicated that the spectral basis of the calibration was not related to C-13/C-12 ratios per se but to consistent differences between grasses and non-grasses in chemical composition and that the differences were modified by photosynthetic pathway. Thus, although the calibration equation could not be used to make valid faecal delta C-13 predictions when the diet contained either C-3 grass or C-4 non-grass, it could be used to make useful estimates of dietary non-grass proportions. It could also be ut :sed to make useful estimates of non-grass in mixed C-3 grass/non-grass diets by applying a modified formula to calculate non-grass from predicted faecal delta C-13. The development of a robust faecal-NIR calibration equation for estimating non-grass proportions in the diets of grazing cattle demonstrated a novel and useful application of NIR spectroscopy in agriculture.
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Hypertension, obesity, dyslipidemia and dysglycemia constitute metabolic syndrome, a major public health concern, which is associated with cardiovascular mortality. High dietary salt (NaCl) is the most important dietary risk factor for elevated blood pressure. The kidney has a major role in salt-sensitive hypertension and is vulnerable to harmful effects of increased blood pressure. Elevated serum urate is a common finding in these disorders. While dysregulation of urate excretion is associated with cardiovascular diseases, present studies aimed to clarify the role of xanthine oxidoreductase (XOR), i.e. xanthine dehydrogenase (XDH) and its post-translational isoform xanthine oxidase (XO), in cardiovascular diseases. XOR yields urate from hypoxanthine and xanthine. Low oxygen levels upregulate XOR in addition to other factors. In present studies higher renal XOR activity was found in hypertension-prone rats than in the controls. Furthermore, NaCl intake increased renal XOR dose-dependently. To clarify whether XOR has any causal role in hypertension, rats were kept on NaCl diets for different periods of time, with or without a XOR inhibitor, allopurinol. While allopurinol did not alleviate hypertension, it prevented left ventricular and renal hypertrophy. Nitric oxide synthases (NOS) produce nitric oxide (NO), which mediates vasodilatation. A paucity of NO, produced by NOS inhibition, aggravated hypertension and induced renal XOR, whereas NO generating drug, alleviated salt-induced hypertension without changes in renal XOR. Zucker fa/fa rat is an animal model of metabolic syndrome. These rats developed substantial obesity and modest hypertension and showed increased hepatic and renal XOR activities. XOR was modified by diet and antihypertensive treatment. Cyclosporine (CsA) is a fungal peptide and one of the first-line immunosuppressive drugs used in the management of organ transplantation. Nephrotoxicity ensue high doses resulting in hypertension and limit CsA use. CsA increased renal XO substantially in salt-sensitive rats on a high NaCl diet, indicating a possible role for this reactive oxygen species generating isoform in CsA nephrotoxicity. Renal hypoxia, common to these rodent models of hypertension and obesity, is one of the plausible XOR inducing factors. Although XOR inhibition did not prevent hypertension, present experimental data indicate that XOR plays a role in the pathology of salt-induced cardiac and renal hypertrophy.
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This project aims to develop integrated irrigation and nutrition management strategies under limited water for irrigators currently investing in overhead irrigation systems (CPLM) to minimize the learning lag in their use and optimize crop and economic performance.
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Laboratory colonies of Bactrocera passiflorae (Froggatt) and B. xanthodes (Broun) were established at Koronivia Research Station, Fiji in 1991. Laboratory rearing of the two economically important species was a prerequisite to studies conducted on protein bait spray and quarantine treatment development. To increase the production of laboratory reared fruit flies for this research and also to have a substitute larval diet available, replicated comparisons of the effectiveness of larval diets were carried out using B. passiflorae and B. xanthodes. The diets compared were pawpaw/bagasse, dehydrated carrot and diets used for culturing Mediterranean fruit fly (Ceratitis capitata Wiedemann), Oriental fruit fly (B. dorsalis Hendel), melon fly (B. cucurbitae Coquillett) and B. latifrons (Hendel), pawpaw diet and breadfruit diet. B. passiflorae and B. xanthodes eggs seeded onto the various diets were allowed to develop into larvae, pupae and adults. The percentage egg hatch, number of pupae recovered, percentage pupal mortality, weight of 100 pupae, number of adults and percentage eclosion were used to determine the effectiveness of the diets. Results showed that pawpaw/bagasse and dehydrated carrot diets performed favorably for both species. The pawpaw diet currently used as standard larval diets for both species is the most readily available and easiest to use. Breadfruit diet was tested on B. xanthodes only and showed that it was a suitable substitute for the pawpaw-based diets. Other larval diets, cassava/pawpaw and banana diets, that have been developed and used in the South Pacific areas are also discussed in this paper. When pawpaw or breadfruit are not available, dehydrated carrot diet may be substituted for fruit-based larval diets.
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Dugongs (Dugong dugon) are marine mammals that obtain nutrients through hindgut fermentation of seagrass, however, the microbes responsible have not been identified. This study used denaturing gradient gel electrophoresis (DGGE) and 454-pyrosequencing to profile hindgut bacterial communities in wild dugongs. Faecal samples obtained from 32 wild dugongs representing four size/maturity classes, and two captive dugongs fed on cos lettuce were screened using DGGE. Partial 16S rRNA gene profiles of hindgut bacteria from wild dugong calves and juveniles were grouped together and were different to those in subadults and adults. Marked differences between hindgut bacterial communities of wild and captive dugongs were also observed, except for a single captive whose profile resembled wild adults following an unsuccessful reintroduction to the wild. Pyrosequencing of hindgut communities in two wild dugongs confirmed the stability of bacterial populations, and Firmicutes (average 75.6% of Operational Taxonomic Units [OTUs]) and Bacteroidetes (19.9% of OTUs) dominated. Dominant genera were Roseburia, Clostridium, and Bacteroides. Hindgut microbial composition and diversity in wild dugongs is affected by ontogeny and probably diet. In captive dugongs, the absence of the dominant bacterial DNA bands identified in wild dugongs is probably dependent upon prevailing diet and other captive conditions such as the use of antibiotics. This study represents a first step in the characterisation of a novel microbial ecosystem-the marine hindgut of Sirenia.
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A high proportion of the Australian and New Zealand dairy industry is based on a relatively simple, low input and low cost pasture feedbase. These factors enable this type of production system to remain internationally competitive. However, a key limitation of pasture-based dairy systems is periodic imbalances between herd intake requirements and pasture DM production, caused by strong seasonality and high inter-annual variation in feed supply. This disparity can be moderated to a certain degree through the strategic management of the herd through altering calving dates and stocking rates, and the feedbase by conserving excess forage and irrigating to flatten seasonal forage availability. Australasian dairy systems are experiencing emerging market and environmental challenges, which includes increased competition for land and water resources, decreasing terms of trade, a changing and variable climate, an increasing environmental focus that requires improved nutrient and water-use efficiency and lower greenhouse gas emissions. The integration of complementary forages has long been viewed as a means to manipulate the home-grown feed supply, to improve the nutritive value and DM intake of the diet, and to increase the efficiency of inputs utilised. Only recently has integrating complementary forages at the whole-farm system level received the significant attention and investment required to examine their potential benefit. Recent whole-of-farm research undertaken in both Australia and New Zealand has highlighted the importance of understanding the challenges of the current feedbase and the level of complementarity between forage types required to improve profit, manage risk and/or alleviate/mitigate against adverse outcomes. This paper reviews the most recent systems-level research into complementary forages, discusses approaches to modelling their integration at the whole-farm level and highlights the potential of complementary forages to address the major challenges currently facing pasture-based dairy systems.
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Cyperus iria is a weed of rice with widespread occurrence throughout the world. Because of concerns about excessive and injudicious use of herbicides, cultural weed management approaches that are safe and economical are needed. Developing such approaches will require a better understanding of weed biology and ecology, as well as of weed response to increases in crop density and nutrition. Knowledge of the effects of nitrogen (N) fertilizer on crop-weed competitive interactions could also help in the development of integrated weed management strategies. The present study was conducted in a screenhouse to determine the effects of rice planting density (0, 5, 10, and 20 plants pot−1) and N rate (0, 50, 100, and 150 kg ha−1) on the growth of C. iria. Tiller number per plant decreased by 73–88%, leaf number by 85–94%, leaf area by 85–98%, leaf biomass by 92–99%, and inflorescence biomass by 96–99% when weed plants were grown at 20 rice plants pot−1 (i.e., 400 plants m−2) compared with weed plants grown alone. All of these parameters increased when N rates were increased. On average, weed biomass increased by 118–389% and rice biomass by 121–275% with application of 50–150 kg N ha−1, compared to control. Addition of N favored weed biomass production relative to rice biomass. Increased N rates reduced the root-to-shoot weight ratio of C. iria. Rice interference reduced weed growth and biomass and completely suppressed C. iria when no N was applied at high planting densities (i.e., 20 plants pot−1). The weed showed phenotypic plasticity in response to N application, and the addition of N increased the competitive ability of the weed over rice at densities of 5 and 10 rice plants pot−1 compared with 20 plants pot−1. The results of the present study suggest that high rice density (i.e., 400 plants m−2) can help suppress C. iria growth even at high N rates (150 kg ha−1).
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A new analogue of vitamin A, viz., retinoic acid anhydride was prepared, for the first time, by the action of thionyl chloride on retinoic acid in benzene containing pyridine. The amhydride was charcterised by its chromatographic properties, elemental analysis, ultraviolet absorption, infrared and nuclear magnetic resonance spectral characteristics. The compound could be readily hydrolysed to retinoic acid both by acid and alkali treatments and reduced by lithium aluminium hydride to vitamin A alcohol (retinol). The spectral changes with antimony trichloride reagent were similar to those observed for retinoic acid. The metabolism of retinoic acid anhydride was found to be similar to that of retinoic acic. When administered either orally or intraperitoneally, the compound promotes growth in vitamin A-deficient rats. Time-course experiments revealed that retinoic acid anhydride is converted into retinoic acid by non-enzymatic hydrolysis and thereby exerts its biological activity. The biopotency of the anhydride was found to be nearly the same as that of the acid. A new method of preparing esters of retinoic acid employing retinoic acid anhydride as an intermediate, has been described.
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This thesis is grounded on four articles. Article I generally examines the factors affecting dental service utilization. Article II studies the factors associated with sector-specific utilization among young adults entitled to age-based subsidized dental care. Article III explores the determinants of dental ill-health as measured by the occurrence of caries and the relationship between dental ill-health and dental care use. Article IV measures and explains income-related inequality in utilization. Data employed were from the 1996 Finnish Health Care Survey (I, II, IV) and the 1997 follow-up study included in the longitudinal study of the Northern Finland 1966 Birth Cohort (III). Utilization is considered as a multi-stage decision-making process and measured as the number of visits to the dentist. Modified count data models and concentration and horizontal equity indices were applied. Dentist s recall appeared very efficient at stimulating individuals to seek care. Dental pain, recall, and the low number of missing teeth positively affected utilization. Public subvention for dental care did not seem to statistically increase utilization. Among young adults, a perception of insufficient public service availability and recall were positively associated with the choice of a private dentist, whereas income and dentist density were positively associated with the number of visits to private dentists. Among cohort females, factors increasing caries were body mass index and intake of alcohol, sugar, and soft drinks and those reducing caries were birth weight and adolescent school achievement. Among cohort males, caries was positively related to the metropolitan residence and negatively related to healthy diet and education. Smoking increased caries, whereas regular teeth brushing, regular dental attendance and dental care use decreased caries. We found equity in young adults utilization but pro-rich inequity in the total number of visits to all dentists and in the probability of visiting a dentist for the whole sample. We observed inequity in the total number of visits to the dentist and in the probability of visiting a dentist, being pro-poor for public care but pro-rich for private care. The findings suggest that to enhance equal access to and use of dental care across population and income groups, attention should focus on supply factors and incentives to encourage people to contact dentists more often. Lowering co-payments and service fees and improving public availability would likely increase service use in both sectors. To attain favorable oral health, appropriate policies aimed at improving dental health education and reducing the detrimental effects of common risk factors on dental health should be strengthened. Providing equal access with respect to need for all people ought to take account of the segmentation of the service system, with its two parallel delivery systems and different supplier incentives to patients and dentists.