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The public perceives that the nutritional quality of eggs produced as free range is superior to that of eggs produced in cages. Therefore, this study compared the nutrient content of free-range vs. cage-produced shell eggs by exam...
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The public perceives that the nutritional quality of eggs produced as free range is superior to that of eggs produced in cages. Therefore, this study compared the nutrient content of free-range vs. cage-produced shell eggs by examining the effects of the laboratory, production environment, and hen age. A flock of 500 Hy-Line Brown layers were hatched simultaneously and received the same care (i.e., vaccination, lighting, and feeding regimen), with the only difference being access to the range. The nutrient content of the eggs was analyzed for cholesterol, n-3 fatty acids, saturated fat, monounsaturated fat, polyunsaturated fat, beta-carotene, vitamin A, and vitamin E. The same egg pool was divided and sent to 4 different laboratories for analysis. The laboratory was found to have a significant effect on the content of all nutrients in the analysis except for cholesterol. Total fat content in the samples varied (P < 0.001) from a high of 8.88% to a low of 6.76% in laboratories D and C, respectively. Eggs from the range production environment had more total fat (P < 0.05), monounsaturated fat (P < 0.05), and polyunsaturated fat (P < 0.001) than eggs produced by caged hens. Levels of n-3 fatty acids were also higher (P < 0.05), at 0.17% in range eggs vs. 0.14% in cage eggs. The range environment had no effect on cholesterol (163.42 and 165.38 mg/50 g in eggs from caged and range hens, respectively). Vitamin A and E levels were not affected by the husbandry to which the hens were exposed but were lowest at 62 wk of age. The age of the hens did not influence the fat levels in the egg, but cholesterol levels were highest (P < 0.001) at 62 wk of age (172.54 mg/50 g). Although range production did not influence the cholesterol level in the egg, there was an increase in fat levels in eggs produced on the range.
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Aim: This paper describes the differences between the NUTTAB and AUSNUT food composition databases now available in Australia,Method: The NUTTAB and AUSNUT food composition databases are described in detail by officers of Food Sta...
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Aim: This paper describes the differences between the NUTTAB and AUSNUT food composition databases now available in Australia,Method: The NUTTAB and AUSNUT food composition databases are described in detail by officers of Food Standards Australia New Zealand directly involved in the database management and development. The positions of Food Standards Australia New Zealand in terms of revisions and policy directions are given from an authoritative perspective.Results: Food Standards Australia New Zealand develops two different sets of food composition databases, NUTTAB and AUSNUT. NUTTAB is a reference database that contains primarily analysed data for Australian foods. AUSNUT is a survey database that contains only data that are directly relevant to the particular national nutrition survey for which it was developed. These databases are available free of change from the Food Standards Australia New Zealand website. Conclusions: Food Standards Australia New Zealand develops two distinct series of food composition databases. Users will need to be aware of the similarities and differences of each database type to be able to determine which is the most suitable for their needs.
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Reports of apparent historical declines in mineral nutrients of vegetables, fruits and grains, allegedly due to soil mineral depletion by agriculture, triggered this critical review. Comparisons of food composition data published ...
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Reports of apparent historical declines in mineral nutrients of vegetables, fruits and grains, allegedly due to soil mineral depletion by agriculture, triggered this critical review. Comparisons of food composition data published decades apart are not reliable. Over time changes in data sources, crop varieties, geographic origin, ripeness, sample size, sampling methods, laboratory analysis and statistical treatment affect reported nutrient levels. Comparisons with matching archived soil samples show soil mineral content has not declined in locations cultivated intensively with various fertilizer treatments. Contemporaneous analyses of modern versus old crop varieties grown side-by-side, and archived samples, show lower mineral concentrations in varieties bred for higher yields where increased carbohydrate is not accompanied by proportional increases in minerals - a "dilution effect". Apparent declines, e.g., the extreme case of copper from -34% to -81%, represent small absolute changes: per 100 g dry weight vegetables have 0.11-1.71 mg (1555% natural range of variation), fruit 01-2.06 mg (20,600% range), and grains 0.1-1.4 mg (1400% range); copper composition is strongly subject to the dilution effect. The benefits of increased yield to supply food for expanding populations outweigh small nutrient dilution effects addressed by eating the recommended daily servings of vegetables, fruits and whole grains. Crown Copyright (C) 2016 Published by Elsevier Inc.
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The nutritional value of shrubs and tree fodders browsed by Tswana goats in Botswana were evaluated, in the first study, seeds from twenty browse species were analysed. Nutrient composition of the seeds varied widely. Crude protei...
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The nutritional value of shrubs and tree fodders browsed by Tswana goats in Botswana were evaluated, in the first study, seeds from twenty browse species were analysed. Nutrient composition of the seeds varied widely. Crude protein content of Bauhania petersiana was 6.42 g/100g while Sterculia africana was 35.59 g/10Og. The second study showed that twigs from five browses varied in tannin and nutrient composition. Acacia tort#is and Grewia flava leaves and twigs had similar crude protein content but their tannin contents differ significantly (p<0.05). The third study was to evaluate available browse resources for Tswana goats reared extensively in South East Botswana. The most commonly occuring species were Acacia erioloba, A. tortilis, Dichrostachys cinerea, G. flava and Terminalia seracea. Browses varied in their seasonal availability but A. tort#is, G. flava and T. seracea were present on the ranges all year round. The fourth study was a feeding trial using yearling males fed buffalo grass hay(Buchloe dactyloides) as basal diet and Acacia nilotica or D. cinerea as supplements to evaluate animal performance on these browses. The fifth study demostrated that A. erubescens and buffalo grass hay fed as supplement to grazing Tswana goats improvedtheir weight gains.
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The nutritional composition of prey is known to influence predator life histories, but how the life history strategies of predators affect their susceptibility to nutrient imbalance is less investigated. We used two wolf spider sp...
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The nutritional composition of prey is known to influence predator life histories, but how the life history strategies of predators affect their susceptibility to nutrient imbalance is less investigated. We used two wolf spider species with different life histories as model predators: Pardosa amentata, which have a fixed annual life cycle, and Pardosa prativaga, which reproduce later and can extend development across 2 years. We fed juvenile spiders of the two species ad libitum diets of one of six Drosophila melanogaster fly types varying in lipid:protein composition during three instars, from the start of the second instar until the fifth instar moult. We then tested for interactions between predator species and prey nutrient composition on several life history parameters. P. amentata completed the three instars faster and grew larger carapaces and heavier body masses than P. prativaga, but the two species responded differently to variation in prey lipid:protein ratio. Duration of the instars increased when feeding on protein-poor prey in P. amentata, but was unaffected by diet in P. prativaga. Likewise, the effect of diet on body composition was more pronounced in P. amentata than in P. prativaga. Prey nutrient composition thus affected the two species differently. During macronutrient imbalance P. amentata appear to prioritize high growth rates while experiencing highly variable body compositions, whereas P. prativaga maintain more constant body compositions and have slower growth. These can be seen as different consequences of a fixed annual and a plastic annual-biennial life cycle.
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Foxtail millet has attained world wide popularity in the recent years due to its nutritive value and therapeutic use. The present study was undertaken to know the nutrient and mineral composition of foxtail millet varieties grown ...
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Foxtail millet has attained world wide popularity in the recent years due to its nutritive value and therapeutic use. The present study was undertaken to know the nutrient and mineral composition of foxtail millet varieties grown in Andhra Pradesh. Foxtail millet varieties namely Prasad, SIA-3058, SIA-3222 and SIA-3156 were selected to analyze nutrient composition. The results of nutritive composition of four varieties of foxtail millet showed that the Moisture, energy, carbohydrate, protein, fat, calcium, iron and zinc contents ranged from 6.63 to 10.56 %, 361.80 to 385.83 kcal, 66.33 to 67.32 g/100g, 12.50 to 14.47 g/lOOg, 3.98 to 5.60 g/100g, 28.69 to 31.71 mg/100g, 2.89 to 3.52 mg/100g and 2.48 to 3.72 mg/100g, respectively. The present study revealed that the values for energy, protein and Zinc are higher in foxtail millet when compared to rice, wheat and quinoa. The fat content of foxtail millet was found to be less than that in quinoa, the calcium and iron content of foxtail millet was highcompared to rice.
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Most landscapes are heterogeneous in vegetation composition and thus, in the distribution of nutrients required by herbivores for growth and reproduction. Hispid cotton rats (Sigmodon hispdus) inhabit Texas coastal prairies which ...
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Most landscapes are heterogeneous in vegetation composition and thus, in the distribution of nutrients required by herbivores for growth and reproduction. Hispid cotton rats (Sigmodon hispdus) inhabit Texas coastal prairies which are characterized by habitat patches dominated by dicots, monocots or both [mixed) plant types. Hispid cotton rat's must obtain nutrients necessary for reproduction by ingesting both dicots and monocots, and reproductive females concentrate their activity in mixed patches. Mixed patches may be selected because they have high nutrient contents or because presence of both monocot and dicot food plants lowers cost of foraging movements. Because hispid cotton rats select a nutritionally complete diet and may detect protein by odor and taste cues, we hypothesized that nutrient concentrations may cue position of foraging paths. We used nutrient maps to measure amount of protein, P and Ca encountered during foraging from radiotracked individuals. We compared these values to those obtained from randomly generated foraging paths. Actual and random paths did not differ in amount of protein, P or Ca encountered. Differences in nutient accumulation between seasons were explained by seasonal differences in availability. We conclude that foraging paths do not respond to nutrient content of plants, but that reproductive females likely occupy mixed habitat patches because presence of both dicot and monocot food plants decreases time and energy spent foraging.
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Most landscapes are heterogeneous in vegetation composition and thus, in the distribution of nutrients required by herbivores for growth and reproduction. Hispid cotton rats (Sigmodon hispdus) inhabit Texas coastal prairies which ...
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Most landscapes are heterogeneous in vegetation composition and thus, in the distribution of nutrients required by herbivores for growth and reproduction. Hispid cotton rats (Sigmodon hispdus) inhabit Texas coastal prairies which are characterized by habitat patches dominated by dicots, monocots or both [mixed) plant types. Hispid cotton rat's must obtain nutrients necessary for reproduction by ingesting both dicots and monocots, and reproductive females concentrate their activity in mixed patches. Mixed patches may be selected because they have high nutrient contents or because presence of both monocot and dicot food plants lowers cost of foraging movements. Because hispid cotton rats select a nutritionally complete diet and may detect protein by odor and taste cues, we hypothesized that nutrient concentrations may cue position of foraging paths. We used nutrient maps to measure amount of protein, P and Ca encountered during foraging from radiotracked individuals. We compared these values to those obtained from randomly generated foraging paths. Actual and random paths did not differ in amount of protein, P or Ca encountered. Differences in nutient accumulation between seasons were explained by seasonal differences in availability. We conclude that foraging paths do not respond to nutrient content of plants, but that reproductive females likely occupy mixed habitat patches because presence of both dicot and monocot food plants decreases time and energy spent foraging.
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Abstract Background Manganese (Mn) is an essential nutrient for plant growth and a key factor driving litter decomposition. Nitrogen (N) deposition is expected to enhance soil Mn availability via soil acidification, and subsequent...
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Abstract Background Manganese (Mn) is an essential nutrient for plant growth and a key factor driving litter decomposition. Nitrogen (N) deposition is expected to enhance soil Mn availability via soil acidification, and subsequently to increase plant Mn concentrations. Aims We aimed to quantify the responses of Mn concentrations in green and senesced shoots at both species and community levels to N addition, and determine whether N addition would decrease Mn retranslocation efficiency during plant senescence. Methods We examined the changes of Mn concentrations in soil and in green and senesced shoots of all plant species across multiple N addition rates ranging from 0 to 50 g N m?2 y?1 in a temperate steppe after six years treatments. Plant Mn retranslocation efficiency were quantified at species, life form, and community levels. The relationship between plant Mn nutritional parameters and soil Mn availability across the N addition gradient was analyzed. Results There were positive correlations between plant Mn concentrations and N addition rates for most species. Relative to the control plots, community‐level mean Mn concentration in green and senesced shoots in the plots received the highest level of N addition increased by 137.50% (from 0.19 mg kg?1 to 0.08 mg kg?1) and 187.50% (from 0.23 mg kg?1 to 0.08 mg kg?1), respectively. There was no correlation between Mn retranslocation efficiency and N addition rates at species, life form and community levels. Plant Mn status was weakly correlated with soil Mn concentrations for most species. Conclusions Plant Mn retranslocation showed conserved responses to increasing N addition rates, which would be an adaptive strategy for plants in face of N‐induced higher soil Mn availability.
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