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Nutrient Deficiencies (nutrient + deficiency)
Selected AbstractsA review of nutritional deficiencies and toxicities in captive New World primatesINTERNATIONAL ZOO YEARBOOK, Issue 1 2000S. CRISSEY The science of providing adequate nutrition for New World primates in captivity has improved dramatically in the past decade. To utilize these advances it is important to be aware of specific metabolic diseases and/or conditions associated with nutrient deficiencies or toxicities seen in New World primates. The non-human primate may require up to 64 dietary nutrients, highlighting the importance of an appropriate diet for optimal health. A review of the major nutritional problems which occur in captive New World primates is presented to provide a basis for good nutritional management of these species. [source] Soil properties and tree growth along an altitudinal transect in Ecuadorian tropical montane forestJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 2 2008Wolfgang Wilcke Abstract In tropical montane forests, soil properties change with increasing altitude, and tree-growth decreases. In a tropical montane forest in Ecuador, we determined soil and tree properties along an altitudinal transect between 1960 and 2450 m asl. In different vegetation units, all horizons of three replicate profiles at each of eight sites were sampled and height, basal area, and diameter growth of trees were recorded. We determined pH and total concentrations of Al, C, Ca, K, Mg, Mn, N, Na, P, S, Zn, polyphenols, and lignin in all soil horizons and in the mineral soil additionally the effective cation-exchange capacity (CEC). The soils were Cambisols, Planosols, and Histosols. The concentrations of Mg, Mn, N, P, and S in the O horizons and of Al, C, and all nutrients except Ca in the A horizons correlated significantly negatively with altitude. The C : N, C : P, and C : S ratios increased, and the lignin concentrations decreased in O and A horizons with increasing altitude. Forest stature, tree basal area, and tree growth decreased with altitude. An ANOVA analysis indicated that macronutrients (e.g., N, P, Ca) and micronutrients (e.g., Mn) in the O layer and in the soil mineral A horizon were correlated with tree growth. Furthermore, lignin concentrations in the O layer and the C : N ratio in soil affected tree growth. These effects were consistent, even if the effect of altitude was accounted for in a hierarchical statistical model. This suggests a contribution of nutrient deficiencies to reduced tree growth possibly caused by reduced organic-matter turnover at higher altitudes. [source] Drought and salinity: A comparison of their effects on mineral nutrition of plantsJOURNAL OF PLANT NUTRITION AND SOIL SCIENCE, Issue 4 2005Yuncai Hu Abstract The increasing frequency of dry periods in many regions of the world and the problems associated with salinity in irrigated areas frequently result in the consecutive occurrence of drought and salinity on cultivated land. Currently, 50% of all irrigation schemes are affected by salinity. Nutrient disturbances under both drought and salinity reduce plant growth by affecting the availability, transport, and partitioning of nutrients. However, drought and salinity can differentially affect the mineral nutrition of plants. Salinity may cause nutrient deficiencies or imbalances, due to the competition of Na+ and Cl, with nutrients such as K+, Ca2+, and NO. Drought, on the other hand, can affect nutrient uptake and impair acropetal translocation of some nutrients. Despite contradictory reports on the effects of nutrient supply on plant growth under saline or drought conditions, it is generally accepted that an increased nutrient supply will not improve plant growth when the nutrient is already present in sufficient amounts in the soil and when the drought or salt stress is severe. A better understanding of the role of mineral nutrients in plant resistance to drought and salinity will contribute to an improved fertilizer management in arid and semi-arid areas and in regions suffering from temporary drought. This paper reviews the current state of knowledge on plant nutrition under drought and salinity conditions. Specific topics include: (1) the effects of drought and salt stress on nutrient availability, uptake, transport, and accumulation in plants, (2) the interactions between nutrient supply and drought- or salt-stress response, and (3) means to increase nutrient availability under drought and salinity by breeding and molecular approaches. Trockenstress und Salzstress , Vergleich der Auswirkungen auf die mineralische Ernährung von Pflanzen Eine Zunahme von Trockenperioden in vielen Ländern der Welt und assoziierte Probleme der Versalzung in bewässerten Gebieten führen häufig zu gleichzeitigem Auftreten von Trockenheit und Salinität. Gegenwärtig sind weltweit ungefähr 50 % aller Bewässerungsflächen durch Salinität beeinträchtigt. Nährstoffstörungen bei Trocken- und Salzstress beeinträchtigen die Verfügbarkeit, den Transport und die Verteilung von Nährelementen in der Pflanze und reduzieren somit das Pflanzenwachstum. Trocken- und Salzstress können sich jedoch unterschiedlich auf die Nährstoffversorgung der Pflanzen auswirken. Salinität kann aufgrund der Konkurrenz zwischen Na+ bzw. Cl, und Nährelementen wie K+, Ca2+ und NO Nährstoffmängel oder -ungleichgewichte in den Pflanzen verursachen. Trockenstress kann sowohl die Nährstoffaufnahme als auch den akropetalen Transport einiger Elemente beeinträchtigen. Trotz kontroverser Schlussfolgerungen in der Literatur hinsichtlich der Wechselbeziehungen von Nährstoffangebot und Trocken- bzw. Salzstress auf das Pflanzenwachstum ist allgemein akzeptiert, dass Nährstoffzufuhr das Pflanzenwachstum nicht verbessert, wenn ausreichend Nährstoffe im Boden verfügbar sind oder bei stark ausgeprägter Trockenheit oder Salinität. Ein besseres Verständnis der Rolle von Mineralstoffen in der Toleranz von Pflanzen gegenüber Trocken- oder Salzstress dürfte gerade in ariden und semi-ariden Gebieten sowie in Regionen, die unter periodischer Trockenheit leiden, zu verbesserten Düngestrategien beitragen. In der vorliegenden Arbeit wird der gegenwärtige Kenntnisstand der mineralischen Ernährung bei Trockenheit und Salinität diskutiert. Schwerpunkte der Betrachtungen sind (1) die Auswirkungen von Trockenheit und Salzstress auf die Verfügbarkeit, die Aufnahme, den Transport und die Anreicherung von Nährelementen in der Pflanze, (2) Wechselbeziehungen zwischen dem Nährstoffangebot und Trockenheit oder Salinität sowie (3) Maßnahmen zur Verbesserung der Nährstoffverfügbarkeit bei Trockenheit und Salzstress mittels züchterischer und molekularbiologischer Ansätze. [source] The role of nutrients in modulating diseaseJOURNAL OF SMALL ANIMAL PRACTICE, Issue 6 2008D. L. Chan The role of nutrition in the management of diseases has often centred on correcting apparent nutrient deficiencies or meeting estimated nutritional requirements of patients. Nutrition has traditionally been considered a supportive measure akin to fluid therapy and rarely it has been considered a primary means of ameliorating diseases. Recently, however, further understanding of the underlying mechanisms of various disease processes and how certain nutrients possess pharmacological properties have fuelled an interest in exploring how nutritional therapies themselves could modify the behaviour of various conditions. Nutrients such as omega-3 fatty acids, antioxidants and certain amino acids such as arginine and glutamine have all been demonstrated to have at least the potential to modulate diseases. Developments in the area of critical care nutrition have been particularly exciting as nutritional therapies utilising a combination of approaches have been shown to positively impact outcome beyond simply proving substrate for synthesis and energy. Application of certain nutrients for the modulation of diseases in veterinary patients is still in early stages, but apparent successes have already been demonstrated, and future studies are warranted to establish optimal approaches. This review describes the rationale of many of these approaches and discusses findings both in human beings and in animals, which may guide future therapy. [source] Paleolithic diets: a sceptical viewNUTRITION BULLETIN, Issue 1 2000Marion Nestle Summary Some anthropologists have suggested that humans are genetically determined to eat diets quite different from those of today. Very little human evolution has occurred in the past 15,000 years. However, diets have changed dramatically and in parallel with a shift in disease patterns from infectious diseases and diseases associated with nutrient deficiencies, to chronic degenerative diseases associated with excessive and unbalanced intake of energy and nutrients. This review examines some of the archaeological evidence relating to the diets of early man and other primates, and current hunter-gatherer societies. Knowledge of the relative proportions of animal and plant foods in the diets of early humans is circumstantial, incomplete, and debatable and there are insufficient data to identify the composition of a genetically-determined optimal diet. The evidence related to Paleolithic diets is best interpreted as supporting the idea that diets based largely on plant foods promote health and longevity, at least under conditions of food abundance and physical activity. [source] Nutrients for Cognitive Development in School-aged ChildrenNUTRITION REVIEWS, Issue 8 2004Janet Bryan Ph.D. This review considers the research to date on the role of nutrition in cognitive development in children, with a particular emphasis on the relatively neglected post-infancy period. Undernutrition and deficiencies of iodine, iron, and folate are all important for the development of the brain and the emergent cognitive functions, and there is some evidence to suggest that zinc, vitamin B12, and omega-3 polyunsaturated fatty acids may also be important. Considerations for future research include a focus on the interactions between micronutrients and macronutrients that might be influential in the optimization of cognitive development; investigation of the impact of nutritional factors in children after infancy, with particular emphasis on effects on the developing executive functions; and selection of populations that might benefit from nutritional interventions, for example, children with nutrient deficiencies or those suffering from attention deficit-hyperactiv-ity disorder and dyslexia. [source] Comparison of the nutrient ecology of coastal Banksia grandis elfinwood (windswept shrub-like form) and low trees, Cape Leeuwin-Naturaliste National Park, Western AustraliaAUSTRAL ECOLOGY, Issue 3 2003KENNETH A. BARRICK Abstract Trees growing along windy coasts often have canopies that are greatly reduced in size by the sculpting effects of wind and salt spray. Trees with environmentally reduced stature are called elfinwood (windswept shrub-form or krummholz) and are ecologically important because they represent outposts growing at the limit of tree success. The purpose of this study was to assess if Banksia grandis elfinwood growing at Cape Leeuwin had a different nutrient status than normal low-form (LF) trees growing nearby, and if nutrient deficiencies, toxicities and/or imbalances were among the limiting factors imposed on elfinwood. The concentrations of N, P, K, Ca, Mg, Na, Cl,, Fe, Mn, Zn, Cu, Mo and B were analysed for mature green foliage, immature foliage, foliage litter, flowers and soil. When the elfinwood and LF trees were compared, the foliar nutrient status was generally similar, except that elfinwood foliage had significantly higher mean concentrations of N, Zn and Cu, while LF trees had higher Fe and Mn contents. Many nutrients were conserved before leaves were shed in both elfinwood and LF trees, including N, P, K, Na, Cl,, Mn and Cu (LF trees also conserved Ca and Mg). However, elfinwood and LF tree-litter contained significantly higher Fe concentrations than green foliage (elfinwood litter also had higher levels of Mg and B). It is tempting to suggest that the translocation of Fe into leaves before they were shed is a regulation mechanism to prevent Fe toxicity, or imbalance in the Fe : Mn ratio. Proteoid roots strongly acidify the soil to mobilize P, which also chemically reduces Fe+3 to plant-available Fe+2. The increased supply of Fe+2 in the rhizosphere, caused by the action of proteoid roots, might tend to defeat self-regulation of Fe uptake. It is possible that excess Fe accumulation in the plant might be regulated, in part, by exporting Fe into the leaves before they are shed. The nutrient status of B. grandis elfinwood is compared with mountain elfinwood of North America. The extreme habitat of coastal elfinwood provides many theoretical pathways for nutrient limitation, but B. grandis elfinwood at Cape Leeuwin does not appear to be nutrient deficient. [source] Resource quality and stoichiometric constraints on stream ecosystem functioningFRESHWATER BIOLOGY, Issue 5 2009SALLY HLADYZ Summary 1. Resource quality and stoichiometric imbalances in carbon : nutrient ratios between consumers and resources can influence key ecosystem processes. In many streams, this has important implications for food webs that are based largely upon the utilization of terrestrial leaf-litter, which varies widely among litter types in its value as a food source for detritivores and as a substrate for microbial decomposers. 2. We measured breakdown rates and macroinvertebrate colonization of leaf-litter from a range of native and exotic plants of differing resource quality and palatability to consumers [e.g. carbon : nitrogen : phosphorus (C : N : P) ratios, lignin and cellulose content], in a field experiment. We also measured C : N : P ratios of the principal leaf-shredding invertebrates, which revealed strong stoichiometric imbalances across trophic levels: C : N and C : P ratios typically differed by at least one order of magnitude between consumers and resources, whereas N : P imbalances were less marked. Application of the threshold elemental ratio approach, which integrates animal bioenergetics and body elemental composition in examining nutrient deficiency between consumers and resources, revealed less marked C : P imbalances than those based on the simpler arithmetic differences described above. 3. Litter breakdown rates declined as nutrient imbalances widened and resource quality fell, but they were independent of whether resources were exotic or native. The principal drivers of total, microbial and invertebrate-mediated breakdown rates were lignin : N, lignin : P and fungal biomass, respectively. However, multiple regression using orthogonal predictors yielded even more efficient models of litter breakdown, as consumers responded to more than one aspect of resource quality. For example, fungal biomass and litter C : N both influenced invertebrate-mediated breakdown. 4. Large stoichiometric imbalances and changes in resource quality are likely to have serious consequences for stream ecosystem functioning, especially when riparian zones have been invaded by exotic plant species whose chemical composition differs markedly from that of the native flora. Consequently, the magnitude and direction of change in breakdown rates and, thus, resource depletion, will be driven to a large extent by the biochemical traits (rather than taxonomic identity per se) of the resident and invading flora. [source] Site history affects soil and plant 15N natural abundances (,15N) in forests of northern Vancouver Island, British ColumbiaFUNCTIONAL ECOLOGY, Issue 3 2000S. X. Chang Abstract 1.,About 10 years after establishment, plantations of Western Redcedar (Thuja plicata Donn ex D. Don) on northern Vancouver Island, British Columbia become nutrient deficient and chlorotic, grow slowly, and are susceptible to invasion by the ericaceous shrub Salal (Gaultheria shallon Pursh.). 2.,To test the hypothesis that ,15N can be related to site histories (site disturbance, soil N dynamics and plant development), we measured soil and foliar ,15N in the summer of 1992 in 3-year-old (nutrient-sufficient) and 10-year-old (nutrient-deficient) plantations and in old-growth stands. The foliar and soil ,15N values of the plantations and old-growth forests were different and closely reflected site histories. Salal invasion and nutrient deficiency interacted to depress the growth of Redcedar in 10-year-old plantations. 3.,Site preparation destroyed the top soil organic layers (fresh and decaying litter) and forced Salal (ecto- and ericoid mycorrhizal) into the humus layer, where it was in direct competition with Redcedar, thereby disadvantaging arbuscular mycorrhizal/non-mycorrhizal Redcedar in its nutrient acquisition during a period when N and P are severely limited. 4.,There was a large seasonal range of foliar ,15N (5·5 and 4·3, for 10-year-old Redcedar and Salal, respectively), and there was no relationship between foliar ,15N and measured rooting depth, demonstrating that rooting depths cannot be used to explain foliar ,15N variation among coexisting woody taxa. 5.,Foliar and soil ,15N declined with site age and with a presumed change from ,open' to ,closed' N cycling; the 15N-depleting effects of mycorrhizal N transformations contributed to the observed ,15N decline. [source] Effects of Interactions of Moisture Regime and Nutrient Addition on Nodulation and Carbon Partitioning in Two Cultivars of Bean (Phaseolus vulgaris L.)JOURNAL OF AGRONOMY AND CROP SCIENCE, Issue 4 2001T. Boutraa Major limitations of bean (Phaseolus vulgaris L.) production in arid and semiarid regions are lack of moisture and low soil fertility. An experiment was conducted to determine the effects of soil moisture and N : P : K (20 : 10 : 10) fertilizer on root and shoot growth of two cultivars of bean: cv. Carioca, an indeterminate Brazilian landrace, and cv. Prince, a determinate cultivar grown in Europe. Carioca appears generally stress-tolerant while Prince is intolerant. Seedlings were grown in pots of non-sterile soil at 30, 60 or 90 % field capacity (FC), and given 0, 0.1 or 1 g (kg soil),1 of compound fertilizer. The soil contained a population of effective Rhizobium. Growth of both cultivars was greatest in the high moisture and high nutrient treatments. Root fractions were highest at low nutrient supply; the effect of water was not significant. Leaf fraction decreased as root fraction increased. Numbers of nodules were highest at high and intermediate moisture when no fertilizer was applied. Numbers were lowest at 30 % FC and at the highest fertilizer rate. Masses of nodules and fractions followed the same pattern. Decreasing water regime reduced the relative growth rate (RGR) of Prince, while Carioca maintained high RGR at unfavourable conditions of water and nutrients. Net assimilation rates (NAR) were unaffected by nutrient addition, and reduced by low moisture regime. Water use efficiencies (WUEs) were reduced by water stress but increased by nutrient deficiency. The water utilization for dry matter production was optimal at 60 % FC. Einflüsse der Interaktionen von Bodendenfeuchte und Düngung auf die Knöllchenbildung und Kohlenstoff verteilung bei zwei Bohnenkultivaren (Phaseolus vulgaris L.) Der begrenzende Hauptfaktor der Bohnenproduktion in ariden und semiariden Regionen sind der Feuchtigkeitsmangel und die Bodenfruchbarkeit. Es wurde ein Experiment durchgeführt, um die Wirkungen des Bodenwassers und von N : P : K (20 : 10 : 10) Dünger auf das Wurzel- und Sproßwachstum an zwei Kultivaren von Bohnen (Phaseolus vulgaris L. cv. Carioca, eine brasilianischen, indeterminierte Landsorte und cv. Prince, eine determinierter in Europa angebauter Kultivar) zu untersuchen. Carioca erscheint grundsätzlich streßtoleranter im Vergleich zu Prince. Die Sämlinge wurden in Gefäßen mit nichtsterilisiertem Boden unter Feldkapazitäten von 30,60 oder 90 % mit 0, 0,1 oder 1 g eines Volldüngers angezogen. Der Boden enthielt eine Population von wirksamem Rhizobium. Das stärkste Wachstum wurde bei beiden Kultivaren unter dem Einfluß des höchsten Feuchtigkeitsgehaltes und der höchsten Düngermenge gefunden. Der Wurzelanteil war bei der geringen Düngermenge am niedrigsten. Der Einfluß der Bodenfeuchtigkeit war nicht signifikant. Der Blattanteil nahm mit zunehmendem Wurzelanteil ab. Die Anzahl der Knötchen war bei hoher und mittlerer Bodenfeuchte und ohne Düngeranwendung am höchsten. Die Anzahl war am geringsten bei 30 % FC und der höchsten Düngermenge. Die Knötchenmasse und ihr Anteil reagierte entsprechend. Abnehmende Bodenfeuchte reduzierte die relative Wachtumsrate (RGR) von Prince, während Carioca einen hohen RGR auch bei ungünstigen Bedingungen bezüglich Wasser und Düngung behielt. Die Nettoassimilationsraten wurden durch die Düngung nicht beeinflußt; sie gingen bei geringer Bodenfeuchte zurück. Die Wassernutzungseffiziens (WUE) wurde bei Wasserstreß reduziert, nahm aber bei Düngermangel zu. Die Wassernutzung für die Trockenmasseproduktion war bei 60 % Feldkapazität am höchsten. [source] 30,Seasonal control of phytoplankton biomass and productivity in coastal british columbia lakes and reservoirsJOURNAL OF PHYCOLOGY, Issue 2003J. M. Davies Factors controlling algal abundance and carbon fixation form a cornerstone of aquatic ecology. Central among these are light, nutrients, and grazers. We measured 14C fixation over one year in six coastal BC lakes that differed in trophic status and grazer community structure. The lakes in our study were never covered with ice, so mixing due to wind energy was more similar to summer months and light levels were higher during winter than comparable ice-covered lakes. Our study, therefore, offered a unique opportunity to examine how seasonal changes in light and temperature affects the functioning of these lakes. While many of our study lakes had higher chlorophyll concentrations during winter months, only the lake with a community dominated by small grazers maintained moderate nutrient deficiency throughout the year and increased 14C-fixation during the winter (Jan,Feb). [source] Acute Versus Marginal Deficiencies of NutrientsNUTRITION REVIEWS, Issue 9 2002Kenneth J. Carpenter Under experimental conditions, an acute nutrient deficiency (e.g., thiamin or folic acid) can be induced in both animal and human subjects. The signs and pathologic changes of an acute deficiency, however, may differ substantially from those seen clinically; often marginal deficiencies have been maintained over a long period of time. [source] Hypervitaminosis A in experimental nonhuman primates: evidence, causes, and the road to recoveryAMERICAN JOURNAL OF PRIMATOLOGY, Issue 10 2009Joseph T. Dever Abstract One of the great underlying assumptions made by all scientists utilizing primate models for their research is that the optimal nutritional status and health of the animals in use has been achieved. That is, no nutrient deficiency or excess has compromised their health in any detectable way. To meet this assumption, we rely on the National Research Council's (NRC's) nutritional recommendations for nonhuman primates to provide accurate guidance for proper dietary formulations. We also rely on feed manufacturers to follow these guidelines. With that in mind, the purpose of this commentary is to discuss three related points that we believe have significant ramifications for the health and well being of captive primates as well as for their effective use in biomedical research. First, our laboratory has shown that most experimental primates are likely in a state of hypervitaminosis A. Second, it is apparent that many primate diets are providing vitamin A at levels higher than the NRC's recommendation. Third, the recommendation itself is based on inadequate information about nutrient needs and is likely too high, especially when compared with human requirements. Am. J. Primatol. 71:813,816, 2009. © 2009 Wiley-Liss, Inc. [source] | ||||||||||||||||