Tesi: "Herbage production"

1

Danby, Sharon. "The effect of slurry and dirty water application to herbage on herbage production, dairy cow productivity and behaviour". Thesis, University of Reading, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.266044.

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2

Wallau, Marcelo Osório. "Modeling the dynamics of herbage production and intake in complex grasslands". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/164622.

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Studies in grassland management and ecology have always been challenging because of the large amount and great variation of the entities representing and affecting the system. Despite that, we were able to progress significantly in range experimentation in the Campos, in Southern Brazil. Along past thirty years, a large amount of data and information was generated, from vegetation production to components of intake. In an attempt to integrate the information available, seeking for a deeper understanding of the functioning of native grasslands, we propose adapting a mechanistic vegetation model, aggregated of a spatialized grazing component to create PampaGraze. This model was developed for temperate perennial grasslands, and was adapted and tested for subtropical, C4-dominated grasslands of the Campos of Southern Brazil (Chapter III). Despite the limited capacity of field data for validating, the model was able to relatively well simulate the trends in vegetation production along the year and seasons, while overpredicting herbage production during peak growing season. The structure of the model as it is did not allow for an accurate simulation slow-growing, tussock-forming species. Further, we developed and integrated a grazing model, based on a hybrid approach of the classical mechanistic equations of the prey model (STEPHENS & KREBS, 1986), and experimental data on foraging behaviour measured on native grasslands (Chapter IV). The model was very successful on predicting the components of intake, and responded well to variation of components in relation to changes in vegetation and to selectivity pressures, compared to available literature. Regardless of the limitations on the vegetation model, we were able to further explore the relationships of components of intake, identifying possible major limitations for herbage consumption, thus animal performance, in native grasslands. A significant progress was achieved with this thesis, but still long ways to go with this project. A list of suggestions for further developments can be found in Chapter V. We identified the emergent needs for field studies on parameters and morphogenesis, for improving predictions of the vegetation model, as well as structural points of the model that could be addressed for better representation of natural phenomena. This thesis is the first step towards a more detailed and reliable tool for studying and predicting the behaviour of vegetation dynamics and animal production in sub-tropical grasslands. This can allow us to explore relationships and scenarios beyond our experimental capacity, and investigate the connectivity of the system, as well as each mechanism separately. The stage has been set, awaiting further developments.

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3

Hobbs, Trevor J., e n/a. "Herbage production modelling and assessment in the arid rangelands of Central Australia". University of Canberra. Applied Science, 1994. http://erl.canberra.edu.au./public/adt-AUC20060725.143830.

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The management and sustainable use of Central Australian rangelands for livestock production and conservation requires improved knowledge of the temporal and spatial distribution of primary production in this region. To provide such information, this thesis investigated methods that could rapidly and efficiently estimate regional herbage biomass production in these arid landscapes. Two different approaches were examined, using (1) ground-based or (2) satellite-based data sources. Soil moisture and herbage growth data were collected over several growth seasons and five landscape types in Central Australia, and the data used to develop a model of soil moisture balance and herbage production for the region. The model has few parameters and only requires inputs of rainfall and potential evaporation to predict daily soil moisture and plant growth. Moisture loss in the 0-500 mm soil profile was modelled using a negative exponential function that depends on available soil moisture and is driven by potential evaporation. The growth of herbage, whilst soil moisture is above wilting point, is a linear function of actual evapotranspiration, with the decay of plant material represented by a logistic curve through time. Soil moisture, herbage biomass and species composition assessments made at hectare and square kilometre scales at four locations within Central Australia were examined to determine if a small sample area could be used to accurately describe the soil and plant conditions at a landscape scale. Moisture levels of the 0-200 and 0-500 mm soil profiles from nine samples were analysed for the beginning and conclusion of a growth season, whilst herbage biomass and species composition from 50 samples were compared at the end of the growth season. Results suggest that mean soil moisture levels determined in a 1 ha area are comparable with mean values in the surrounding 1 km2 area. Herbage biomass and species richness for a square kilometre can be assessed at a hectare site for some landscape types, but a larger sampling area (> 1 ha) is recommended for most rangeland assessments. Satellite data (NOAA-11) were examined for their potential application in assessing primary productivity in Central Australia. Several image correction techniques were tested to minimise the adverse effects of atmospheric contamination and illumination. Two measures of atmospheric moisture: (1) radiosonde data and (2) temperature differences between bands 4 and 5 of the NOAA satellite (split-window) were used to explain variations in NOAA-11 normalised difference vegetation index (NDVI) on inert desert sites. The splitwindow approach provided the best single factor relationship (r2=0.63) and, when combined with scattering angle (illumination) effects, up to 81% of the variation in NDVI data could be explained. Field measurements of herbage biomass were correlated with four growth indices derived from NOAA-11 NDVI data. The influence of preflight and sensor degradation calibrations of Bands 1 and 2, and atmospheric correction techniques were also tested. Correlations between temporal sums of NDVI and herbage biomass data were relatively poor (r2<0.42) and unsuitable for herbage assessment in Central Australia. However, correlations between atmospherically corrected and background-adjusted maximum NDVI data and observed herbage biomass were strong (r2=0.91), that will allow primary production in the arid rangelands of Central Australia to be assessed rapidly and efficiently using remotely-sensed information.

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4

Bailey, J. S. "Evaluation of the lime requirements of some soils for grass production". Thesis, Queen's University Belfast, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379218.

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5

Armendariz-Yanez, Ivan Rene. "Indigenous fodder legume trees : their influence on soil fertility and animal production on tropical pastures of Yucatan, Mexico". Thesis, Imperial College London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.285231.

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6

Razmjoo, Ghalaie Khorshid. "Effect of potassium, sulfur, boron, and molybdenum fertilization on alfalfa production and herbage composition /". The Ohio State University, 1985. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487260859495673.

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7

Nhlengetfwa, Melusi. "A mathematical model of browse and herbage production in communal grazing lands of semi-arid regions". Master's thesis, University of Cape Town, 1999. http://hdl.handle.net/11427/26527.

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The main purpose of this work is to extend an existing model of growing cattle and grass production in a semi-arid rangeland.The existing model which is basically Dye's (1983) model in differential equation form handles: i) the growth and performance of cattle measured in terms of weight, ii) the initiation of grass growth in early rainy season and its utilisation by the cattle . This model is being extended to simulate woody plants in addition to the grass and to simulate browsing by goats. The densities of vegetation and the stocking rates of both types of animals are being considered. Our model (SAVANNAS) will predict animal productivity in relation to rainfall and density of woody plants (or vegetation condition). A rainfall data file is being used to generate rain which divides into infiltration and run-off. Athough generally dry, semi-arid regions are agriculturally productive, more especially in terms of animal products. An understanding of the climatic conditions by the farmers is all what it takes. It is unfortunate that in these regions, rainfall, being the main driving force behind animal productivity, is unreliable in that it varies both within and over the years. It is in this regard, therefore, that models be built to simulate semi-arid environments. Such models, when run for several (semi-arid) representative rainfall years could be used by farmers. For instance, a model like SAVANNAS will be run for three rainfall years namely 1980/81, 1981/82 and 1982/83, which, respectively represent: very high, about average and very low rainfall (by semi-arid standards). SAVANNAS simulates processes that operate on widely different time scales. The growth and consumption of herbage and leaves and twigs of woody plants are modelled on a daily basis, while the numbers and ages of woody plants are updated every 120 days. The year is divided into four seasons, with the rainy season beginning in September and initiating herbage re-growth. SAVANNAS simulates herbage biomass, which means it allows the re-establishment of the previous year's grass plants . It divides woody plants into age cohorts with the first cohort being seedlings mainly, and the last cohort being adult trees which are usually out of the browsing range of herbivores. It is a model that has a focus on the effects of vegetation (woody plants and grass) on each other and the effects of the animals on vegetation and viceversa. Without overlooking their effects on vegetation production, fires are not considered in SAVANNAS. This is because in communal lands heavy grazing does not allow the accumulation of sufficient dry herbage for fuel.

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8

Hao, Jun [Verfasser]. "Influence of grazing system on herbage production and animal performance in the Inner Mongolian steppe, China. / Jun Hao". Kiel : Universitätsbibliothek Kiel, 2013. http://d-nb.info/103119066X/34.

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9

Roman, Juliano. "Relação planta-animal em diferentes intensidades de pastejo com ovinos em azevém anual (Lolium multiflorum Lam.)". Universidade Federal de Santa Maria, 2006. http://repositorio.ufsm.br/handle/1/10895.

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This work aimed to evaluate the utilization of different grazing intensity on the productive and structural characteristics of pasture and on the ingestive behaviour and performance of sheep in continuous grazing. The treatment were different herbage masses (HM) in Italian ryegrass (Lolium multiflorum Lam.) pasture: LHM: 1000-1200 kg/ha of dry matter (DM); IHM: 1400-1600 kg/ha DM; HHM: 1800-2000 kg/ha DM. The experimental design was the randomly complete, with three treatments and two area replicates. The data were submitted at the regression analysis in function of HM observed in the experimental units: 1136.8, 1190.9, 1359.2, 1375, 1556 e 1739.1 kg/ha DM. The values of leaf lamina mass, pseudostem mass, forage allowance, leaf lamina allowance, sward height, pseudostem height, leaf lamina depth and average daily gain increased linearly with increase of HM (P<0.10). Quadratic effect (P<0.10) in herbage production, herbage losses and herbage disappearance were observed. The stocking rate (kg/ha of live weight and hoggets/ha) and bite rate decreased linearly with increase of HM (P<0.10). No HM effects (P>0.10) on the tiller population density, herbage daily accumulation rate, percentage of pasture utilization, herbage intake, grazing time, ruminating time, idle time, number of daily bite, bite mass, body condition score gain, live weight gain per area and conversion efficiency of forage in live weight were observed. Herbage mass varying among 1136.8 a 1739.1 hg/ha DM in Italian ryegrass pasture affect the herbage production and herbage losses, without influence in the percentage of pasture utilization, weight gain per area and conversion efficiency of forage in animal product. The main factor determining individual performance of animals is the leaf lamina layer depth
O objetivo deste trabalho foi avaliar a utilização de diferentes intensidades de pastejo sobre as características produtivas e estruturais da pastagem e sobre o comportamento ingestivo e desempenho de ovinos em pastejo contínuo. Os tratamentos foram diferentes massas de forragem (MF) em pastagem de azevém anual (Lolium multiflorum Lam.): MFB: 1000-1200 kg/ha de matéria seca (MS); MFI: 1400-1600 kg/ha MS; MFA: 1800-2000 kg/ha MS. O delineamento experimental foi inteiramente casualizado com três tratamentos e duas repetições de área. Os dados foram submetidos à análise de regressão em função das MF observadas nas unidades experimentais: 1136,8, 1190,9, 1359,2, 1375, 1556 e 1739,1 kg/ha MS. Os valores de massa de lâminas foliares e de pseudocolmo, oferta de forragem e de lâminas foliares, altura de dossel e de pseudocolmo, profundidade de lâminas foliares e ganho médio diário aumentaram linearmente com aumento da MF (P<0,10). Houve efeito quadrático (P<0,10) para produção, perdas e desaparecimento de forragem. A carga animal (kg/ha PV), taxa de lotação (borregas/ha) e taxa de bocadas diminuíram linearmente com o aumento da MF (P<0,10). Não houve efeito das MF avaliadas (P>0,10) na densidade populacional de perfilhos, taxa de acumulação diária de forragem, porcentagem de utilização da pastagem, consumo de forragem, tempos de pastejo, ruminação e ócio, número diário de bocadas, massa de bocado, ganho de condição corporal, ganho de peso vivo por área e eficiência de conversão de forragem em peso vivo. Massas de forragem variando de 1136,8 a 1739,1 kg/ha MS em pastagem de azevém afetam a produção e perdas de forragem, sem influenciar a porcentagem de utilização da pastagem, o ganho de peso vivo por área e a eficiência de transformação da forragem em produto animal. O principal fator determinante do desempenho individual dos animais é a profundidade da camada de lâminas foliares

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10

Anindo, David Owino. "Effect of milking and post calving supplementation on the performance and herbage intake of different crossbred beef cows and their calves in a semi-arid area of Kenya". Thesis, University of Aberdeen, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277278.

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The effects on production of milking grazed crossbred cattle (32, 53 and 74 cow and heifer dams in experiments 1, 2 and 3 in 1986, 1987 and 1988 respectively) with or without a dietary supplement (2kg dairy meal daily for 3 to 4 months post-partum) were studied in a semi-arid area of Kenya. During the second and third trials, half the calves from the milked and also the unmilked groups were creep fed for 4 months commencing approximately 1 month from birth. Herbage dry matter intake was determined four times during the wet and dry seasons between November 1988 and May 1989, and the deterministic model and computer program of the bioenergetic system of lactating and pregnant cattle of Bruce et al (1984) used to examine the performance of the crossbred cows, and to evaluate its potential applicability. The respective mean extracted milk yields over a six month lactation were 670.6, 414.4 and 371.2 kg for the milked and supplemented (MS) groups, and 563.4, 398.4 and 331.1 kg for the unsupplemented (MNS) groups during experiments 1, 2 and 3 (P> 0.05). Mean daily calf growth rates were affected by milk offtake (P< 0.05). They were respectively, 0.52, 0.48, 0.79 and 0.71 kg during experiment 1; 0.64, 0.61, 0.72 and 0.72 kg during experiment 2; and 0.59, 0.57, 0.66 and 0.66 kg during experiment 3 for the milked (MS and MNS) and the control groups (not milked and supplemented, NMS and the not milked and not supplemented, NMNS). Overall, post-partum supplementation improved dam liveweight gain (P< 0.05) but milk extraction tended to reduce it (P> 0.05). Similarly, calving indices were improved by supplementation while the effect of milking was inconsistent. Both creep feeding of the calves and beef genotypes of the dams were not significant (P> 0.05) factors affecting performance. Similarly, body condition scores (1 to 9 score scale) ranged between condition score 4 and 5 for all treatments. The respective mean daily dry matter intakes were 8.5 and 8.2 during the wet, and 8.6 and 8.2 kg during the dry periods; and the corresponding dry matter digestibilities were 0.72 and 0.74 in the wet, and 0.67 and 0.62 during the dry periods. The discrepancies between observed and predicted values of milk (energy), though not for liveweight, were small, consequently, with a few refinements the bioenergetic model may find a useful role in cattle production systems in the semi-arid tropics. It was concluded that the offtake of milk from suitable crossbred cattle in the semi-arid areas may be increased without significantly reducing offtake of slaughter animals.

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11

Savian, Jean Victor. "Rotatinuous stocking : an innovation in grazing management based on animal behaviour and implications to pasture production, foraging behaviour, herbage intake and methane emission by grazing sheep". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/158949.

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The aim of this thesis was to investigate contrasting pasture management strategies on the foraging behaviour, pasture production, carcass characteristics, herbage intake, faecal gas emissions and methane emission by sheep grazing Italian ryegrass (Lolium multiflorum) pastures. The experiment was carried out in 2014 and 2015. The experimental design was a randomized complete block with four replicates and two grazing strategy treatments (traditional rotational stocking method – RT meaning pre- and post-grazing target heights of 25 and 5 cm, respectively and, “rotatinuous stocking” – RN with pre- and post-grazing target heights of 18 and 11 cm, respectively). The grazing management was based on a 1-day strip-grazing regime. Male castrated sheep were used. The actual average sward heights for the RN treatment were 17.9 and 11.1 cm (pre- and post-grazing, respectively) and 27.1 and 7.8 cm for the RT (pre- and post-grazing, respectively). The stocking period in 2014 was 146 and 140 days (RN and RT, respectively) and in 2015 it was 155 and 146 days (RN and RT, respectively). The diurnal animal activities (grazing, ruminating and resting time) did not differ between treatments, with average of 439.6, 166.9 and 85.0 minutes, respectively. The bite rate, feeding station per min and steps per min were greater at the RN than the RT treatment. Grazing time and bite rate were greater in the afternoon than morning in both treatments. Therefore, the daily herbage intake by sheep grazing Italian ryegrass was greater for the RN than the RT treatment (CHAPTER II). The herbage production in the RN was 28% higher than the RT treatment. Individual average daily gain and live weight gain per hectare were greater in the RN than the RT treatment (CHAPTER III). RN treatment presented greater final live weight, carcass and commercial cut weights from grazing sheep than RT treatment (CHAPTER IV). RN treatment had a faecal chemical quality greater than RT treatment, resulting in a greater daily nitrogen excretion per animal and greater faecal CH4 and N2O emissions (CHAPTER VI). The “rotatinuous stocking” (RN) was the better grazing management strategy for mitigation of CH4 emissions by sheep grazing Italian ryegrass, emitting 64% less CH4 per unit area and 170% less CH4 per unit of animal product than the traditional rotational stocking method (RT) (CHAPTER V).

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12

Küchenmeister, Frank [Verfasser], Johannes [Akademischer Betreuer] Isselstein, Klaus [Akademischer Betreuer] Dittert e Nicole [Akademischer Betreuer] Wrage-Mönnig. "Sustainable grassland herbage production under drought stress - the role of plant species number and functional group composition / Frank Küchenmeister. Gutachter: Johannes Isselstein ; Klaus Dittert ; Nicole Wrage-Mönnig. Betreuer: Johannes Isselstein". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2013. http://d-nb.info/104441460X/34.

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13

Dickeduisberg, Michael [Verfasser], Johannes [Akademischer Betreuer] Isselstein, Johannes [Gutachter] Isselstein e Harald [Gutachter] Laser. "Management and drought effects on growth and herbage yield of Tall Wheatgrass (Agropyron elongatum) for biogas production in Central Europe / Michael Dickeduisberg ; Gutachter: Johannes Isselstein, Harald Laser ; Betreuer: Johannes Isselstein". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2018. http://d-nb.info/1163806129/34.

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14

Seither, Melanie [Verfasser], Johannes [Akademischer Betreuer] Isselstein, Klaus [Akademischer Betreuer] Dittert e Wolfram [Akademischer Betreuer] Beyschlag. "The effect of grassland botanical composition and (co-) grazing cattle and sheep on herbage production and sward nutrient utilisation / Melanie Seither. Gutachter: Johannes Isselstein ; Klaus Dittert ; Wolfram Beyschlag. Betreuer: Johannes Isselstein". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2011. http://d-nb.info/1043765522/34.

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15

Seither, Melanie Verfasser], Johannes [Akademischer Betreuer] Isselstein, Klaus [Akademischer Betreuer] Dittert e Wolfram [Akademischer Betreuer] [Beyschlag. "The effect of grassland botanical composition and (co-) grazing cattle and sheep on herbage production and sward nutrient utilisation / Melanie Seither. Gutachter: Johannes Isselstein ; Klaus Dittert ; Wolfram Beyschlag. Betreuer: Johannes Isselstein". Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2011. http://nbn-resolving.de/urn:nbn:de:gbv:7-webdoc-3134-4.

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16

Lopes, Marília Lazzarotto Terra. "Sistema de integração lavoura-pecuária : desempenho de novilhos superprecoces e rendimento subseqüente da cultura de soja". reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2008. http://hdl.handle.net/10183/15389.

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O objetivo do experimento foi avaliar o desempenho e a qualidade da carcaça de novilhos superprecoces submetidos a alturas de manejo de pastos de aveia preta e azevém anual (10, 20, 30 e 40 cm) e uma testemunha sem pastejo, bem como avaliar os efeitos dessas alturas de manejo sobre o estabelecimento e o rendimento da cultura de soja subseqüente. O experimento foi realizado na Fazenda do Espinilho, município de Tupanciretã, entre julho de 2004 e maio de 2005. Animais jovens com idade média de dez meses e peso inicial de 190 kg foram distribuídos num delineamento experimental de blocos ao acaso, com três repetições. As ofertas diárias de forragem para os tratamentos 10, 20, 30 e 40 cm foram, respectivamente, 8,8, 14,7, 29,0 e 48,9 kg de matéria seca/100 kg de peso vivo (PV). O ganho de peso por hectare foi superior nos tratamentos com menor altura de manejo, em decorrência da maior carga animal empregada, sendo 529,7, 489,5, 320,9 e 201,6 kg de PV/ha, para os respectivos tratamentos. O ganho médio diário e peso ao abate apresentaram resposta quadrática (P<0,05) conforme o incremento na altura do pasto. A deposição de gordura apresentou média de 3,8 mm e o rendimento médio de carcaça fria foi de 53,3% (P<0,05). As alturas reais do pasto ficaram próximas daquelas pretendidas, havendo um aumento linear da massa de forragem com o aumento das alturas de manejo do pasto. A taxa de acúmulo não foi afetada pelos tratamentos. A taxa de lotação apresentou resposta linear decrescente com o aumento da altura do pasto. A massa de forragem remanescente aumentou na medida em que houve incremento na altura de manejo do pasto. Foi observada diferença entre os tratamentos para palhada residual e estande inicial de plantas de soja, porém, essas diferenças não afetaram o rendimento de grãos da cultura. Concluiu-se que novilhos superprecoces atingem peso de abate e grau de acabamento adequados quando terminados em pastagem de inverno e suplementados no terço final do ciclo de pastejo. O melhor ganho médio diário foi obtido em altura entre 25 a 30 cm e a maior produção por área em 10 cm de altura. A utilização de pastos durante o inverno não prejudica o rendimento de grãos na cultura de soja subseqüente, possibilitando aumento da renda do produtor pela oportunidade de gerar receitas durante a entressafra da soja.
This trial aimed to evaluate the performance and carcass quality of “superprecoce” steers grazing oat and annual ryegrass pastures managed at 10, 20, 30 and 40 cm with a no grazing reference, as well as sward height management effects on soybean establishment and grain yield. The experiment was carried at Fazenda do Espinilho, Tupanciretã municipality, from July 2004 until May 2005. Young animals with 10 months on average and initial live weight of 190 kg were distributed in a randomized block design with three replicates. The daily herbage allowances were 8.8, 14.7, 29.0 and 48.9 kg of dry matter/100kg of live weight, respectively treatments. The live weight gain per hectare was superior in treatments with lower management heights, due to the greater stocking rate employed, being 529.7, 489.5, 320.9 and 201.6 kg of LW, respectively for the treatments 10, 20, 30 and 40cm height. The average daily gain and slaughter weight increased with pasture height being fitted by a quadratic model (P<0.05). The fat deposition and the medium dressing of cold carcass averaged 3.8mm and 53.3%, respectively (P<0.05). The actual sward heights were very similar to those previously intended. There was a linear increase in herbage mass with the increase of sward height. The pasture accumulation rate was not influenced by treatments. The stocking rate showed a decreased linear response with increasing sward height. Post grazing herbage mass increased with increasing sward height. Treatments had effect on initial soybean stand, but not in soybean yield. It was concluded that “superprecoce” steers can reache slaughter weight and adequately finishing degree when finished in winter cultivated pasture supplemented in final third of the grazing cycle. Better individual animal performance is obtained when pasture height ranges from 25 to 30 cm and animal production per hectare when the pasture was managed at 10 cm height. Results suggest grazing animals do not damage succeeding soybean crop, allowing farmers profitability enhancement during soybean intercropping.

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17

Rojas-Torres, Lilian, e César Tume-Chávez. "Estudio de pre-factibilidad para la implementación de una planta de producción de crema hidratante a base de camu camu y jalea real". Bachelor's thesis, Universidad de Lima, 2015. http://repositorio.ulima.edu.pe/handle/ulima/3294.

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El siguiente proyecto de investigación tiene como finalidad determinar si es rentable la implementación de una planta de elaboración de crema corporal hidratante a base de camu camu y de jalea real. Hoy en día el mercado del cuidado personal ya no es sólo cuestión de cuidar la imagen sino también la salud, es por eso que en el presente es uno de los negocios más rentables.
The main objective of the following research is to determine the successful of installing a factory of a hydrating body lotion of Camu camu and Royal jelly. Nowadays, the hygiene and personal care market is one of the most rentable business because the more someone invest in this topic the better personal image in a healthy body they will have.
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18

Van, Heerden Ilse. "Evaluation of a phytogenic product from two western herbal medicines to replace an antimicrobial growth promoter in poultry production". Thesis, University of Pretoria, 2010. http://hdl.handle.net/2263/28482.

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Antimicrobial growth promoters (AGPs) are substances that are added to feed in sub-therapeutic levels in intensive animal production to improve weight gain and conversion of feed (FCR) into body mass. AGPs have been used widely as growth promoters in broiler and pig production under high-density growth conditions. Despite the observed efficacy, the use of AGPs has been criticized due to its possible role in the development of antibiotic resistance in human pathogens. Directive 183/2003 of the European Parliament, issued in 2003, banned of the use of all antibiotic agents as growth promoters in the European Union from 2006. The new context caused an increase in the search for alternative growth promoters. The aim of this study was to produce a commercially viable prophylactic antibacterial phytogenic product from Ginkgo biloba and Hypericum perforatum with a low potential to develop resistance, as an alternative to AGPs in poultry production. The first objective of this study based on earlier results of the Phytomedicine Programme, was to evaluate the activity and potentize extracts from Ginkgo biloba and Hypericum perforatum for optimal activity against relevant bacterial pathogens. Extracts of ethyl acetate (EA), hexane, dichloromethane (DCM) and acetone (in order of activity) from a direct extraction procedure of powdered G. biloba leaves were active against Enterococcus faecalis, Staphylococcus aureus and Clostridium perfringens. The EA, hexane and DCM extracts were 2 to 3 times more active than the acetone extract (average total activity 1728 ml/g dry extract for the 3 pathogens). The DCM-, EA-, acetone- and hexane extracts (in order of activity) from the direct extraction procedure from H. perforatum were only active against C. perfringens with the first three extracts having a total activity of between 1026 and 1333 ml/g dry material and the hexane extract a total activity of 333 ml/g dry material. The spectrum of activity of G. biloba corresponds to that of Zn-bacitracin, which is commonly used an antibiotic growth promoter in the poultry industry. The second objective in this study was to combine extracts or fractions of extracts of G. biloba and H. perforatum to optimise activity against selected bacterial pathogens. A synergistic effect could be observed when combining a ratio of 1:5 of G. biloba: H. perforatum (hexane extracts) or 1:15 (acetone extracts) against E. faecalis while only an indifferent (neutral) effect was observed against C. perfringens. After elucidation of the quantitative and qualitative aspects involved in the antimicrobial activity, the major antibacterial compound from G. biloba was isolated and characterized as ginkgolic acid (C17:1). It was also determined whether activity against E. faecalis and C. perfringens in an extract or fraction of and extract of G. biloba can be attributed only to ginkgolic acid or whether synergism or other interactions also play a role in the antibacterial activity. It was shown that synergistic interactions are at play between constituents in the hexane and EA fraction, with the last mentioned fraction not containing any ginkgolic acid. These results support the use of the whole extract as opposed to isolated compounds as antimicrobial agents against pathogenic organisms. Two important pharmacodynamic parameters were investigated i.e. resistance development to a hexane extract and the isolated ginkgolic acid from G. biloba against E. faecalis and secondly the time-kill dynamics of this hexane extract over 24 h against E. faecalis. The bactericidal nature of the hexane extract from G. biloba as well the absence of decreased susceptibility to this extract (and the isolated ginkgolic acid) in the resistance studies against E. faecalis indicate that this extract has potential to be exploited as a alternative to AGPs in the poultry industry. The final objective was to determine the effect of extracts of G. biloba alone or in combination with H. perforatum extracts on the performance of broiler chickens over a 35 day period. The effect of these extracts on C. perfringens in the intestine of broilers was also investigated. No significant differences were found with relation to any of the production parameters studied (FCR, live weight or % survival) although a trend towards more favourable European Performance Efficiency Factor index values were observed for treatments containing G. biloba (5% improvement) or a combination of G. biloba and H. perforatum (2.1% improvement) compared to the untreated control. Similarly, Zn-Bacitracin resulted in a 5.5% improvement compared to the untreated control. There was a general trend (not statistically significant, P=0.05) towards a reduction in C. perfringens scores in the feed supplemented with G. biloba- in combination with H. perforatum extract which can probably be ascribed to the direct antimicrobial effect. The rate of colonization was however too low to cause infection probably due to lack of virulence of the C. perfringens challenge and the absence of predisposing factors due to the hygienic growth conditions used. It is necessary for an effective disease model to be developed in order for the efficacy of any new treatment method to be properly evaluated. Such a model will require a much higher incidence of disease and reproducibility than was achieved in this project. The safety of using extracts of G. biloba with ginkgolic acid as the prime antibacterial compound was considered. The active dose was at least 42 times lower than safe dosage recommended in the literature. The combination of extracts of G. biloba and H. perforatum holds promise as a potential growth promoter in poultry production. Better results may be achieved if potentized extracts are used and compared with Zn-Bacitracin and a negative control under industrial growth conditions where the birds are stressed and natural infections would take place. Copyright
Thesis (PhD)--University of Pretoria, 2009.
Paraclinical Sciences
unrestricted

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19

Anderson, Victoria M. "CALENDULA OFFICINALIS GROWTH AND PRODUCTION OF SECONDARY COMPOUNDS IN GREENHOUSE AND SOIL-BASED HERBAL ORGANIC PRODUCTION SYSTEMS". UKnowledge, 2013. http://uknowledge.uky.edu/pss_etds/26.

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Calendula officinalis is a useful model crop because calendula flowers are used both ornamentally and medicinally. Organic production systems have many challenges; among these is the synchrony of nitrogen mineralization with the requirements of the crop. Organic greenhouse substrates have significantly different initial nitrogen levels which influence the performance of calendula, the highest initial N and plant performance was found in the organic compost peat substrate (OCP). The addition of supplemental nitrogen improved performance, but only OCP performed as well as the conventionally fertilized peat-based substrate. The nitrogen mineralization patterns in a soil-based greenhouse pot experiment showed that highly processed amendments supplied the highest levels of nitrogen, and that these amendments showed greater vegetative growth when soil was amended with a high-input amendment, but flower production was reduced. There was no observed influence of water stress on nitrogen mineralization, but flowers from water stressed plants had approximately 50% higher concentrations of secondary compounds than non-stressed flowers. Nitrogen mineralization in organic production systems is difficult to predict, but highly influences plant productivity and performance.

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20

Wai, Wing-yin Eric. "Effect of herbal medicine (Ganoderma lucidum) on nitric oxide production in macrophages". Click to view the E-thesis via HKUTO, 2003. http://sunzi.lib.hku.hk/hkuto/record/B3197126X.

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21

衛穎賢 e Wing-yin Eric Wai. "Effect of herbal medicine (Ganoderma lucidum) on nitric oxide production in macrophages". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B3197126X.

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22

Tracol, Yann. "Etude des variations interannuelles de la production herbacée des pâturages sahéliens : exemple du Gourma malien". Toulouse 3, 2004. http://www.theses.fr/2004TOU30032.

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Fortement dépendante de la disponibilité en eau du sol, et donc du régime de la mousson ouest africaine, la dynamique saisonnière et interannuelle de la végétation herbacée sahélienne montre une forte variabilité spatiale et temporelle de la production végétale. L'objectif principal de cette thèse est d'analyser et de caractériser le fonctionnement du tapis herbacé à l'aide de la modélisation et de mesures de terrain pour expliquer les variations de la production primaire en relation avec les forçages externes principalement de nature climatique mais aussi biotique comme l'activité pastorale. L'analyse de mesures récoltées durant la période 1984-2002 dans une région du Sahel, le Gourma malien, démontre une réponse complexe du tapis herbacé face aux contraintes environnementales en terme de production mais aussi de recouvrement et diversité. Par ailleurs, les mesures sur l'ensemble du Gourma contribuent à décrire un gradient nord-sud de la végétation en relation avec la variabilité spatiale des précipitations en terme de cumul et de distribution. Le modèle de fonctionnement STEP (Sahelian Transpiration Evaporation and Production model) adapté aux zones arides simule à l'échelle de la station, le bilan hydrique et l'évolution journalière de la masse herbacée épigée. Le fonctionnement de la végétation herbacée est alors quantifié à l'aide des efficiences d'utilisation de la lumière et de l'eau dérivées des simulations. .
Strongly constrained by the soil water content and consequently by the West African Monsoon, the herbaceous layer shows a large space-time variability. The main goal of this thesis is to analyse and characterise the Sahelian grassland functioning thanks to models and field measurements to explain the primary net production variability in relation with a large number of forcing climatic and biotic variables like pasture pressure. The analysis of data recorded between 1984 and 2002 in a Sahel zone, the Malian Gourma shows us a complex response of the herbaceous strata in terms of production, fraction cover and diversity. Moreover, the field measurements available for the Gourma permit to describe a north-south gradient of vegetation according to the spatial variability of annual rainfall. .

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23

Brau-Nogué, Catherine. "Dynamique des pelouses d'alpages laitiers des Alpes du Nord externes". Université Joseph Fourier (Grenoble ; 1971-2015), 1996. http://www.theses.fr/1996GRE10004.

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Les alpages laitiers des alpes du nord externes (france) representent un type de systeme ecologique original refletant les effets des pratiques d'eleveurs (fertilisation, paturage) combines aux contraintes du milieu montagnard (etage subalpin). Face aux mutations recentes des modes d'exploitation des alpages, des recherches ont ete engagees pour comprendre et prevoir l'impact des pratiques pastorales sur la dynamique de ces pelouses d'altitude. Nous proposons un modele d'evolution de la composition botanique qui integre l'effet des facteurs anthropiques et celui des facteurs edaphiques. Ce modele s'appuie sur une analyse factorielle des correspondances portant sur un echantillonnage de six cent releves floristiques couvrant l'ensemble de la zone d'etude. La reconstitution des trajectoires dynamiques se fait principalement par une approche synchronique, completee par des observations diachroniques qui ont permis de preciser les vitesses d'evolution de la vegetation. L'essentiel des travaux porte sur des situations de deprise: la dynamique de la vegetation y reflete une degradation de la fertilite des sols consecutive a l'abandon ou a l'allegement de la fertilisation. Cette evolution est generalement lente: deux a cinq decennies sont necessaires pour que l'on enregistre des changements notables dans la composition botanique. Les resultats mettent egalement en evidence l'influence des parametres edaphiques sur les limites et le deroulement de ces successions. Les modalites d'evolution de la vegetation et la hierarchie des facteurs sont precisees dans des trajectoires-types qui permettent d'adapter localement la demarche de diagnostic ecologique. Differents indicateurs, relatifs aux processus physiologiques ou demographiques d'evolution de la vegetation, sont testes afin de preciser ou d'anticiper le diagnostic floristique. Les indices de diversite specifique ou factorielle restent d'un usage delicat en raison de leur sensibilite a l'egard des methodes d'echantillonnage et d'observation. Les indices de nutrition minerale font rapidement apparaitre les modifications d'equilibres trophiques qui suivent l'arret ou la reprise de la fertilisation

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24

Tounsi, Ibtissem. "Utilisation des systèmes d'information géographiques pour l'estimation de la production primaire herbacée sahélienne : application au Gourma malien". Paris 1, 1995. http://www.theses.fr/1995PA010626.

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L'objectif de ce mémoire est de présenter un modèle spatialisé d'estimation de la production primaire herbacée du Sahel malien (le gourma) de 1986 à 1990, à l'échelle régionale. Cette estimation est effectuée au moyen d'un modèle statistique mettant en relation la production primaire herbacée avec les données géographiques, climatiques et écologiques. L'utilisation de données du satellite noaa-avhrr permet d'envisager une extension spatiale des mesures effectuées sur les quelques sites tests. Le système d'information géographique (s. I. G. ) permet la manipulation de ces données. La méthodologie proposée présente l'avantage d'être reproductible sur plusieurs années. Elle permet de bien restituer la quantité, les variations spatiales et interannuelles de la production primaire. Ce travail a montré l'importance des prétraitements des données de terrain et satellitaires utilisées afin de permettre des comparaisons interannuelles. Malgré les résultats très positifs du point de vue quantitatif, nous avons observé des incertitudes quant aux valeurs estimées. Ce fait s'explique en partie par une méconnaissance encore importante de la physique des mesures satellitaires et par le manque de données concernant certaines variables clefs du système
The purpose of this thesis is an assessment of malian herbaceous primary production at a regional scale from 1986 to 1990. The assessment of primary production is derived from a statistical spatial model which correlates the linear relationships between herbaceous primary production and geographical, climatic and ecological data. The use of coarse resolution satellite noaa-avhrr data allows the spacialization of field data. The proposed method allows using geographic information system (g. I. S. ) In order to assess primary production. This method can be yearly reproduced. It is also efficient for space-time assessment of variations of primary production. In spite of encouraging quantitative results, there is a strong uncertainty about assessment of herbaceous production primary values. This feature can be partly explained throughout a lack of knowledge concerning physics of remote sensing measurements. Another source of errors is the lack of certain key parameters important of environment

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25

Velazquez, Cruz Lucero Abigail. "EFECTO DE UN COMPUESTO POLIHERBAL SOBRE LA RESPUESTA PRODUCTIVA E INMUNOLÓGICA DE BECERRAS HOLSTEIN". Tesis de doctorado, Universidad Autónoma del Estado de México, 2020. http://hdl.handle.net/20.500.11799/109946.

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El objetivo de la presente investigación fue evaluar el efecto de un compuesto poliherbal (basado en Withania somnifera, Ocimum tenuiflorum, Tinospora cordifolia y Emblica officinalis) a diferentes dosis en becerras Holstein, sobre la respuesta productiva e inmunológica. El experimento tuvo una duración de 67 días para el cual se emplearon cuarenta becerras Holstein de 20 a 25 días de edad con un peso inicial de 43.35 kg ± 2.41 kg. Los animales se distribuyeron aleatoriamente en corrales individuales para su posterior asignación a cada tratamiento experimental los cuales consistían en administrar diariamente dosis orales del compuesto poliherbal (ImmuPlus, Nuproxa) a 0.0, 2.0, 3.0 y 4.0 g d-1. La mejor respuesta productiva se observó con las dosis de 2 y 3 g d-1, al mostrarse una respuesta cuadrática en el peso final, la ganancia diaria de peso (GDP) y la circunferencia torácica final. El consumo de alimento iniciador se redujo linealmente, sin embargo, a medida que aumentaba la dosis del compuesto poliherbal se presentó una respuesta cuadrática en la ingesta del sustituto lácteo y la conversión alimenticia. Para la GDP se estimó mediante regresión una dosis optima del compuesto poliherbal la cual fue de 2.05 ± 0.63 g d-1. En la incidencia de eventos patológicos, tanto digestivos, respiratorios y óticos, así como las dosis de antibióticos no se presentó ningún efecto, no obstante, aumentaron las concentraciones de inmunoglobulinas (lineal y cuadrático). Se mostró una respuesta cuadrática en los linfocitos, los neutrófilos segmentados y de banda, así como las proteínas plasmáticas. La glucosa y la urea en sangre manifestaron una reducción lineal, en cambio la bilirrubina aumento de manera lineal con la dosificación del compuesto poliherbal. La digestibilidad aparente de la materia seca no se modificó (P > 0.05), no obstante, presento una tendencia creciente al implementar en la alimentación el compuesto poliherbal. En la producción de gas in vitro se observaron cambios (P < 0.05) en el volumen máximo de producción de gas, la fase lag, la tasa de producción de gas y la degradabilidad de la materia seca. Se presentó un efecto positivo al disminuir la emisión de gas metano (P < 0.01) con la dosis de 3 g d-1. El compuesto poliherbal a dosis de 2.05 ± 0.63 g d-1 a través de la alimentación mejoró la respuesta productiva e inmunológica de becerras lactantes Holstein, obteniendo como resultado animales más sanos y una adecuada producción.
UAEM

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26

Jouven, Magali. "Quels équilibres entre production animale et utilisation durable des prairies dans les systèmes bovins allaitants herbagers ? : une approche par modélisation des interactions conduite-troupeau-ressources". Phd thesis, INAPG (AgroParisTech), 2006. http://pastel.archives-ouvertes.fr/pastel-00002272.

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La viabilité des systèmes herbagers repose sur leur capacité à produire de la viande à partir des fourrages récoltés sur l'exploitation; leur durabilité environnementale est liée à une utilisation des prairies favorable à la diversité floristique. L'objectif de la thèse était de comprendre les déterminants de la production animale et de l'utilisation durable des prairies à partir d'une analyse multi-échelle des interactions entre le troupeau et les ressources herbagères. Dans ce but, nous avons construit et utilisé un modèle de simulation à l'échelle de l'exploitation qui reproduit le fonctionnement en rythme de croisière d'exploitations bovines allaitantes herbagères. Le modèle est basé sur le couplage d'un sous-modèle de l'animal et d'un sous modèle du couvert végétal, adaptés d'après des modèles existants et validés sur données expérimentales. Un sous-modèle de conduite, construit d'après la bibliographie et trois enquêtes en exploitation et validé par des experts, gère les interactions entre le troupeau et les ressources fourragères. Avec le modèle, nous avons simulé les équilibres entre production animale et utilisation durable des prairies pour trois exploitations contrastées par leur structure et leurs objectifs de production. Nous avons appliqué des niveaux croissants de règles de conduites supposées favorables à la biodiversité (fauche après le stade floraison, pâturage peu sévère). Les prévisions du modèle ont mis en évidence le rôle prépondérant de l'équilibre entre chargement animal et productivité des prairies. La conduite a également joué un rôle, en agissant sur la dynamique des interactions entre le troupeau et les prairies. A des niveaux d'application intermédiaires, les règles de conduite testées ont permis de maintenir la production animale tout en améliorant l'utilisation durable des prairies. La sensibilité à ces règles de conduite a cependant varié entre exploitations simulées. D'autres scénarios structure-conduite pourront être explorés. Le modèle pourra être utilisé en synergie avec des modèles économiques ou des modèles biologiques à des échelles inférieures. Ses entrées et sorties pourront être discutés avec des acteurs du développement pour évaluer leur applicabilité sur le terrain.

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27

Latchman, Yvette Eglantina. "Atopic eczema : a comparison of Zemaphyte, a traditional Chinese herbal treatment and corticosteroids on CD23 expression, cytokine production and cell mediated function in vitro". Thesis, University College London (University of London), 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396626.

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28

Hugonnet, Mickaël. "Transformations des systèmes de production du lait en Nouvelle-Zélande : perte d’autonomie et financiarisation". Thesis, Paris, Institut agronomique, vétérinaire et forestier de France, 2018. http://www.theses.fr/2018IAVF0021.

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Cette thèse porte sur l’évolution des systèmes de production du lait et des systèmes agraires néo-zélandais. Elle vise à expliquer et caractériser l’orientation particulière prise par le développement de la production laitière en Nouvelle-Zélande, laquelle a longtemps reposé sur des systèmes herbagers avant de s’en détourner à partir des années 1990. Il s’agit également de comprendre les mécanismes sous-jacents à l’émergence de structures de production du lait financiarisées. Enfin elle évalue les conséquences socio-économiques de la perte d’autonomie des systèmes de production et de la financiarisation. Cette recherche a mobilisé le cadre théorique de l’Agriculture comparée et s’est également appuyée sur le courant anglo-saxon des « Agrarian studies ». Elle a reposé sur l’analyse-diagnostic de la situation agraire de deux petites régions agricoles (Haute-vallée de Thames et Région de Selwyn). Nos travaux montrent l’importance du contexte économique et politique pour expliquer l’orientation de la production laitière néo-zélandaise vers des systèmes herbagers. Ils mettent également en évidence le rôle central de la libéralisation de l’économie pour expliquer la tendance à la perte d’autonomie observée depuis 1990. L’analyse économique montre que les systèmes herbagers demeurent toutefois performants en termes de création de valeur ajoutée et de revenu agricole par hectare. De son côté, si la financiarisation de la production laitière a permis d’accélérer son développement sur l’île Sud, elle n’a pas conduit à la mise en œuvre de systèmes de production plus performants en termes de création de valeur ajoutée. En revanche, elle amène à ce qu’une part importante de cette valeur ajoutée soit captée par des investisseurs ne prenant pas part au procesus productif. Au final, la question se pose de la pertinence du développement agricole à l’œuvre en Nouvelle-Zélande depuis les années 1990 du point de vue du développement durable
This thesis looks at the evolution of dairy farming and agrarian systems in New Zealand. It explains and characterizes the original path followed by dairy production in this country, which relied on low-input grazing systems until the 90s before moving away from it. It aims also at describing mechanisms underlying the emergence of financialised dairy production structures. Finally, we assess the socio-economic implications of both the shift toward higher-input dairy systems and the financialization of dairy production. This research uses the theoretical framework of Comparative agriculture supplemented by the Anglo-Saxon branch of Agrarian studies. It relied on the analysis-diagnosis the agrarian situation of two small rural areas (the Upper Thames Valley and the Selwyn district). Our work shows how fundamental has been the economic context to explain the focus on low-input grazing systems which characterised dairy farming in the New Zealand until the 90s. It argues that the economic liberalization has been a huge incentive for farmers to shift towards higher-input systems during the 90s. The economic analysis show that low-input systems are nevertheless more efficient in terms of added value and farm income generated per hectare. For its part, financialization permitted to accelerate the development of dairy production, but did not lead to more efficient production systems in terms of added value generated. However, it allows investors who do not take parts into the productive process to capture a significant part of this added value. Finally, the question arises whether or not the agricultural development observed in New Zealand since the 90s is relevant in terms of sustainable development

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29

DIAZ, GALVAN CESAR 655085, e GALVAN CESAR DIAZ. "Efecto de la inclusión de menta, clavo, eucalipto y monensina sódica en la fermentación ruminal y la producción de metano in vivo". Tesis de maestría, Universidad Autónoma del Estado de México, 2017. http://hdl.handle.net/20.500.11799/68402.

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Efecto de especias sobre producción de gas en rumiantes
El objetivo de este estudio fue evaluar el efecto de la inclusión de 1, 2 y 3 % de eucalipto (Eucalyptus spp), clavo (Syzygium aromaticum) y menta (Mentha piperita), así como 0.20 ppm de monensina sódica en una dieta para ovinos en finalización sobre la fermentación ruminal y producción de metano in vitro. Se registraron las lecturas de presión y volumen de gas a las 3, 6, 9, 12, 24, 36, 48, 60 y 72 h, evaluando volumen máximo de gas, tasa de producción de gas, fase lag, degradabilidad de la materia seca, CH4, CO2 y ácidos grasos volátiles (AGV). Los datos obtenidos fueron analizados mediante un diseño completamente al azar, comparando las medias con una prueba de Tukey (P<0.05), además de realizar un arreglo factorial 3 x 4, determinando las interacciones entre las tres plantas y los cuatro niveles. Las dietas con monensina sódica y eucalipto presentaron una disminución en el volumen máximo de gas (P=0.0001), así como menor producción de CH4 (P=0.01) y CO2 (P=0.004); la producción de AGV mostró diferencias (P=0.01) en ácido acético con el 1 % de eucalipto, además de menor producción de ácido butírico (P=0.01), mientras que con el 2 % aumentó (P=0.01) el ácido propiónico y se obtuvo una menor relación acético:propiónico. Al emplear eucalipto sin monensina, se presentó una disminución en tasa de producción de gas (P=0.0008), así como menor producción de gas (P=0.0001) y degradabilidad (P=0.0007), por otro lado al emplear menta la fase lag fue menor (P=0.0001) y se observó mayor reducción en CO2 y CH4 (P=0.0001), finalmente la adición del clavo redujo la tasa de producción de gas (P=0.0004). Por lo cual se concluye que el uso de eucalipto al 3 % disminuye el volumen máximo de gas, tasa de producción de gas así como producción de CH4, además de incrementar la producción de ácido propiónico.

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30

Rotz, Jonathan Daniel. "Comparison of techniques for estimating pasture herbage mass and productive ground cover for Lakota prairie grass, Kentucky 31 endophyte free tall fescue, Kentucky 31 endophyte infected tall fescue and Quantum 542 tall fescue grazed by stocker steers". Thesis, Virginia Tech, 2006. http://hdl.handle.net/10919/42188.

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In terms of acreage, forage is the number one crop in Virginia. The backbone of these forages has long been tall fescue (Lolium arundinaceum (Schreb.) S.J. Darbyshire). Knowledge of the plant species that make up a pasture and the relative amounts of each species present is important for interpreting potential animal performance. It is also important to know the relative amounts and types of weeds present and to monitor for the presence of poisonous plants or noxious weeds. An experiment was conducted in 2003 through 2005 to investigate botanical composition and yield of â Lakotaâ prairie grass (Bromus catharticus Vahl.), â Kentucky 31â endophyte-infected (KY31 E+), endophyte-free (KY31 E-), and â Quantumâ tall fescue (non toxic endophyte infected) under grazing by stocker steers. Forage botanical composition and yield were determined by clipping three 0.25-m2 areas per treatment replicate. Prior to harvesting, the canopy height within each quadrate was measured with a disc meter. In 2005, productive ground cover was assessed using visual evaluation techniques, point quadrat method, and digital imagery quantified with terrestrial remote sensing. Forages were established September 2002 and grazing was initiated in July of 2003. Experimental design was a randomized complete block with four replications. Averaged over the three years the yield of KY31E+ was higher (p<0.05) than all other treatments. Lakota prairie grass had lower (p<0.05) yields than both KY31 E+ and Quantum tall fescue, however no yields did not differ between Lakota prairie grass and KY31 E-. Our results showed a typical forage distribution curve for all the treatments. Early spring, summer, and fall productivity of Lakota prairie grass was less than all the fescues, thus did not extend the grazing season. Forage persistence was greatest for KY31 E+ and Quantum and lowest for Lakota when averaged over all years. Among sampling methods for ground cover, terrestrial remote sensing was the most accurate, compared with visual evaluation and point quadrat methods. For estimates of all yield indirect methods of assessment had high errors; however the plate meter calibrated by sward density seemed the least variable of the methods tested.
Master of Science

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31

Pellet, Gilles. "Phytoécologie, phytosociologie et potentialités fourragères des pelouses d'altitude en Oisans (Alpes françaises) : application à la vallée du Chazelet (la Grave, Hautes-Alpes)". Grenoble 1, 1986. http://www.theses.fr/1986GRE10126.

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Nous abordons une description ecologique et une interpretation phytosociologique des paturages de la vallee du chazelet. Une comparaison bibliographique avec diverses monographies placees dans les alpes internes francaises nous permet de placer notre territoire dans un contexte biogeographique plus general. En relation avec l'activite agricole (fauchage et paturage), nous determinons les potentialites fourrageres des pelouses selon leur appartenance phytosociologique. Une cartographie illustre ce point en vue d'une gestion rentable mais preservatrice des alpages. Enfin, l'utilisation simultanee de deux modes d'echantillonage de la vegetation nous a permis de realiser une comparaison methodologique pour l'estimation des qualites pastorales d'une pelouse

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32

Charpentier, Alexia. "Régulation et prévision de l’ingestion des chèvres laitières au pâturage". Thesis, Poitiers, 2018. http://www.theses.fr/2018POIT2303/document.

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Dans un contexte de fluctuation des prix des intrants et d’une demande croissante en produits à base de lait de chèvre issus de pratiques respectueuses de l’environnement et des animaux, le pâturage peut retrouver une place plus importante dans l’alimentation des chèvres laitières. D’après la synthèse bibliographique, les facteurs de variation de l’ingestion et des performances au pâturage ont été très peu étudiés chez les chèvres laitières en conditions tempérées. L’objectif de la thèse a été de comprendre quelle est l’influence des pratiques de gestion du pâturage (disponibilité en herbe et en temps pour pâturer) sur la régulation de l’ingestion et les performances des chèvres laitières, dans le but d’affiner les recommandations aux éleveurs et d’élaborer les bases d’un modèle de prévision de l’ingestion. D’après les 6 essais réalisés : (1) les chèvres recevant entre 0,6 et 1,0 kg/j de compléments s’adaptent à des restrictions de temps d’accès de 11 à 6 h/j, en augmentant leur vitesse d’ingestion et surtout le pourcentage du temps passé à pâturer jusqu’à 95 % du temps d’accès, (2) les chèvres recevant 0,6 kg de concentrés et un temps d’accès d’au moins 11 h/j peuvent s’adapter à une restriction de quantité d’herbe offerte jusqu’à 2,3-2,6 kg MS/chèvre/j, (3), le poids vif et la production laitière sont des paramètres déterminant de la quantité d’herbe ingérée alors que la parité et le stade de lactation n’ont pas montré d’effet significatif. Ce travail a permis d’établir les premières lois de réponse d’ingestion, de production laitière et d’adaptation comportementale des chèvres laitières à des variations de temps d’accès et de quantité d’herbe offerte au pâturage
In the context of prices volatility and growing demand for goat's milk products from respectful practices of the environment and animals, grazing can become more important in the diet of dairy goats. According to the literature review, the factors of variation of intake and performance of grazing dairy goats have been poorly studied under temperate conditions. The aim of this thesis was to understand the influence of grazing management practices (availability of pasture and access time to grazing) on the regulation of intake and performance of dairy goats, with the aim of refining recommendations for farmers and to elaborate a model of intake prediction. Based on the six trials conducted: (1) goats receiving between 0.6 and 1.0 kg/day of supplements adapt themselves to access time restrictions from 11 to 6 h/d, by increasing their intake rate and especially the percentage of time spent grazing up to 95% of access time, (2) goats receiving 0.6 kg of concentrates and an access time of at least 11 h/day can adapt to a restriction of pasture allowance up to 2.3-2.6 kg DM/goat/day, (3) live weight and milk production are the main variables affecting intake while parity and stage of lactation had no significant effect. This work provides the first response laws of intake, milk production and behavioural adaptation of grazing dairy goats to variations of access time to pasture and to pasture allowance

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Hess, Manon. "Restauration écologique des communautés végétales après éradication d'espèces invasives : Rôle de la dynamique de colonisation et des effets de priorité Using limiting similarity to enhance invasion resistance: theoretical and practical concerns Priority effects: Emerging principles for invasive plant species management Giving recipient communities a greater head start and including productive species boosts early resistance to invasion". Thesis, Avignon, 2020. http://www.theses.fr/2020AVIG0357.

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Les plantes invasives posent d’importants problèmes environnementaux et de santé publique, et leur contrôle est aujourd’hui un défi majeur. Elles rencontrent des conditions particulièrement favorables après des perturbations conduisant à une suppression du couvert végétal. La mise en place d’un couvert végétal séquestrant rapidement ces ressources parait alors une réponse probante pour réduire l’invasion. Néanmoins, les caractéristiques des communautés nécessaires pour exercer une résistance efficace dans les premières phases d’installation sont encore peu connues.Je me suis intéressée à deux mécanismes qui pourraient influencer la résistance à l’invasion des communautés végétales herbacées lors des premiers stades d’installation après une perturbation majeure, que sont (1) la ‘limiting similarity’, impliquant que la coexistence d’espèces partageant la même niche écologique est limitée par l’exclusion compétitive, et (2) les effets de priorité, qui surviennent lorsque l’installation d’une espèce affecte la performance ou la survie d’une espèce arrivant par la suite. L’examen de la littérature confirme que l’application de la ‘limiting similarity’ pour lutter contre les plantes invasives est complexe et n’a, jusqu’à aujourd’hui, fait preuve d’efficacité. Intégrer les effets de priorité aux méthodes de contrôle des plantes invasives après une perturbation semble d’avantage prometteur. Une des stratégies consiste en la mise en place d’un couvert végétal exerçant de forts effets de priorité négatifs, diminuant le succès d’installation des plantes invasives. Deux expérimentations en serre ont été réalisées à cet effet, visant à jouer sur les effets de priorité de la communauté native receveuse afin d’en comprendre l’implication dans la résistance à l’invasion. Dans une première expérimentation, le temps d’avance de la communauté receveuse sur l’arrivée de trois espèces invasives (i.e. Ambrosia artemisiifolia, Bothriochloa barbinodis et Cortaderia selloana), la composition en espèces et la densité des semis ont été manipulés. Une meilleure résistance à l’invasion a été observée lorsque les communautés produisent une forte biomasse aérienne, cette dernière étant associée à la présence d’espèces productives. Retarder l’arrivée des espèces invasives a également réduit le succès d’invasion, mais ceci uniquement lorsque la production de biomasse était suffisamment importante. Une seconde expérimentation a porté sur l’influence de l’identité de la première espèce installée dans la communauté receveuse ainsi que l’ordre de semis des espèces (semis simultané de la communauté ou séquentiel) sur la structuration de la communauté et les conséquences sur sa résistance à l’invasion par A. artemisiifolia. Des différences minimes dans la dynamique de colonisation de la communauté receveuse a substantiellement affecté sa structure, sa production de biomasse, la concentration du sol en nutriments, ainsi que sa résistance précoce à l’invasion. Le semis séquentiel a généralement diminué la résistance à l’invasion par rapport au semis simultané de l’ensemble de la communauté. Les espèces installées en premier ont généré des effets de priorité d’intensité variable, vraisemblablement par le biais de la compétition racinaire, impactant l’invasibilité.En conclusion, la dynamique de colonisation a considérablement influencé le succès d'invasion par le biais de différences de production de biomasse et de préemption des ressources. Les effets de priorité des communautés récemment établies et la résistance à l'invasion associée pourraient être améliorés en (1) maximisant le temps d’avance à la communauté receveuse par rapport aux espèces invasives, (2) introduisant des espèces capables de produire rapidement de la biomasse et de préempter les ressources du sol, et (3) évitant le semis séquentiel, en particulier lorsque les premières espèces installées sont des espèces productives fixatrices d'azote
Invasive plant species cause serious environmental and sanitary issues and their control is today a major challenge. Disturbances involving vegetation removal and an increase in resource availability offer particularly favorable conditions for invasive plant colonization. Establishing a plant cover rapidly sequestering resources could be a relevant strategy to limit invasion. However, little is known about the characteristics enabling newly established communities to exert strong invasion resistance, especially in the early growth stages.In this thesis, I focused on two potential determinants of invasion resistance of herbaceous plant communities in the early growth stages after a major disturbance, which are (1) the concept of limiting similarity, stating that the coexistence of species sharing the same ecological niche is limited by competitive exclusion, and (2) priority effects, which occur when the establishment of a species affects the performance or survival of later arriving species. The application of limiting similarity to control invasive plants appears complex, ineffective and unsuitable for the most common situations. In contrast, integrating priority effects into invasive plant management strategies seems more promising. One strategy consists in restoring a plant cover exerting strong negative priority effects, decreasing the success of subsequent invasive plant establishment. In two greenhouse experiments, I explored the role of priority effects in early invasion resistance. In a first experiment, I manipulated species composition, sowing density and the elapsed time between community sowing and invasion by Ambrosia artemisiifolia, Bothriochloa barbinodis and Cortaderia selloana. A higher invasion resistance was observed when communities produced a high aboveground biomass, which was associated with the presence of productive species. Delaying invasive species arrival also decreased invasion success, but only if it allowed a sufficient increase in biomass production. A second experiment investigated how the identity of the first native colonizer (one of two grasses: Dactylis glomerata and Lolium perenne, or one of two legumes: Onobrychis viciifolia and Trifolium repens) and the timing of species establishment (synchronous vs. sequential sowing) influenced the structuration of the recipient community and its resistance to invasion by A. artemisiifolia. Small differences in assembly history of the recipient community substantially affected community structure, biomass production, soil nutrient content, as well as early invasion resistance. Sequential sowing generally decreased invasion resistance compared with a synchronous sowing. Early colonizers generated priority effects of variable strength most likely via belowground competition, which affected A. artemisiifolia’s invasion success. A prior establishment of the N-fixing legume T. repens particularly boosted A. artemisiifolia’s performance. In conclusions, this thesis work highlights the inadequacy of revegetation strategies based on limiting similarity and reveals promising perspectives of manipulating assembly history and priority effects for designing invasion resistant communities. Assembly history significantly influenced early invasion success by inducing differences in biomass production and resource preemption by the recipient community. Priority effects of newly established communities and associated invasion resistance could be enhanced by (1) giving as much time advance as possible to the recipient community over invasives, (2) introducing species displaying an ability to rapidly produce biomass and preempt soil resources, or (3) avoiding sequential sowing especially when early colonizers are nitrogen-fixing, productive species

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Grouzis, Michel. "Structure, productivité et dynamique des systèmes écologiques sahéliens (Mare d'Oursi, Burkina Faso)". Paris 11, 1987. http://www.theses.fr/1987PA112339.

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Cette étude traite de la structure, de certains aspects du fonctionnement et de l'évolution des phytocénoses sahéliennes du bassin versant d'Oursi, situé au nord du Burkina Faso. Après avoir· rappelé les conditions sahéliennes (aridité climatique, édaphique, saisonalité, variabilité. . . ) le problème du déséquilibre entre les besoins d'une population en expansion et les ressources limitées du milieu est posé. L'étude aborde ensuite la méthodologie relative à la précision des mesures dans l'estimation des phytomasses épigée et hypogée par les techniques classiques de la récolte et radiométrique. Les résultats recueillis de 1976 à 1984 à l' échelle de la station écologique, du bassin versant et de la région portent sur : ( 1) la structure de la végétation ( spectre floristique et biologique de la strate herbacée, densité et structure démographique du peuplement ligneux) (2) la mise en place du peuplement herbacée (productiondes semences propriétés germinatives, établissement des plantules) ; ( 3) la phénologie, la productivité de la végétation épigée et hypogée et, leur déterminisme écologique. Une expression de la production en fonction des précipitations est proposée pour estimer· la production et la capacité de charge fréquentielles ; ( 4) les conditions de la dégradation et les capacités de régénération de la végétation définies par les effets de la mise en défens sur la flore, la phytomasse, l' efficience en eau, la densité des ligneux et par les effets d'aménagements (travail du sol, reboisement. . . ). Ces caractéristiques de structure et de dynamique actuelle associées à certains aspects de la dynamique historique (évolution climatique, occupation ancienne) permettent d' élaborer un modèle de la dynamique du système écologique sahélien. Celui-ci montre que ce système écologique est d'une grande complexité qui sous une relative homogénéité physionomique masque une grande diversité floristique, structurale, fonctionnelle et évolutive. Sous l'effet conjugué de la persistance de la sécheresse et surtout de l' anthropisation, ce système écologique est le siège de processus de dégradation conduisant à sa désertisation progressive. A l'issue de cette analyse des axes prioritaires de recherches (définition des caractéristiques de l' équilibre écologique, de leur seuil de rupture, des conditions de régénération et de restauration. . . ) sont proposés
This work mainly deals with the spin crossover phenomenon in cobalt (II} molecular chemistry. The synthesis of a series of five and six coordinated complexes, with Schiff bases as equatorial ligands and various apical ones, are reported. The temperature dependances of magnetic susceptibilities and EPR spectra are used to study the influence of the environment on the metal ion spin state. The behaviours observed are interpreted on the basie of simple models. Evidence is provided for thermally induced s = 1/2 - s -= 3/2 spin crossavers. In other respects, a correlation can be established between the geometry and spin state of these complexes and their ability to activate molecular oxygen. In order to specify the spin-crossover mechanism, structural and thermodynamic techniques are used: the ingle-crystal X-ray structure of one of the compounds is reported; the mean variation of metal-ligand diatances upon transition is evaluated by X-ray absorption spectroscopy; enthalpy and heat capacity changes, measured by t ose, are compared with the values calculated on the basis of a phenomenological model. A new means of detecting the crossover, by using its effect r. N he EPR spectrum of a Cu (II)doping ion, is described in the case of an iron(II)complex

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PATTY, LAURENT. "Limitation du transfert par ruissellement vers les eaux superficielles de deux herbicides (isoproturon et diflufenicanil) : méthodologie analytique et étude de d'efficacité de bandes enherbées". Université Joseph Fourier (Grenoble), 1997. http://www.theses.fr/1997GRE10057.

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Les travaux presentes dans ce memoire se rapportent a l'etude de la capacite d'un dispositif enherbe experimental, a limiter le transfert par ruissellement de deux herbicides : l'isoproturon (ipu) et le diflufenicanil (dff), qui presentent des proprietes physico-chimiques differentes. Le dispositif, implante a la station i. T. C. F. De la jailliere, a ete suivi au cours de quatre campagnes d'etude en conditions de pluies naturelles, et face a deux ruissellements de plus grande amplitude generes par simulation de pluie. Apres avoir developpe et valide des methodes de dosage sensibles et specifiques de chaque produit et de chaque matrice etudiee, l'analyse des ruissellements collectes a permis de caracteriser le transfert par ruissellement de l'ipu et du dff et d'evaluer l'efficacite des bandes enherbees a reduire ce tranfert. Les resultats provenant des dispositifs implantes dans les stations i. T. C. F. De bignan, plelo et la jailliere, ont confirme et elargi les conclusions a d'autres produits : le lindane, l'atrazine et deux de ses metabolites. Dans les diverses conditions pedoclimatiques, les quantites de produits transferees par ruissellement sont inferieures a 1 % de la dose epandue ; les episodes de ruissellement les plus proches de l'application etant a l'origine des pertes les plus importantes. Les resultats relatifs a l'efficacite des bandes enherbees montrent que differents mecanismes contribuent a la retention de ces residus : l'infiltration de l'eau et des molecules solubilisees (ipu, atrazine) dans le sol, la filtration et la sedimentation des particules solides sur lesquelles sont adsorbes des composes tres peu solubles (dff, lindane) et l'adsorption des molecules solubilisees en surface de la bande. Les dispositifs etudies permettent notamment d'ecreter les pics de concentration des differents composes dans le ruissellement. Les analyses de sol revelent, par ailleurs, que les residus d'ipu et de dff pieges ne s'accumulent pas dans la bande enherbee.

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Kesting, Stefan. "Shrub encroachment of temperate grasslands: Effects on plant biodiversity and herbage production". Doctoral thesis, 2009. http://hdl.handle.net/11858/00-1735-0000-0006-B044-0.

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37

Kesting, Stefan [Verfasser]. "Shrub encroachment of temperate grasslands : effects on plant biodiversity and herbage production / vorgelegt von Stefan Kesting". 2009. http://d-nb.info/999986740/34.

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38

Küchenmeister, Frank. "Sustainable grassland herbage production under drought stress - the role of plant species number and functional group composition". Doctoral thesis, 2013. http://hdl.handle.net/11858/00-1735-0000-001D-C0F8-D.

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Grünlandfutter mit einem hohen Ertrag und gutem Futterwert ist eine Grundvoraussetzung für die effiziente Produktion von wiederkäuenden Nutztieren. Im Zuge des prognostizierten Klimawandels werden sich die Niederschlagsmuster ändern und das Auftreten von Extremwetterereignissen, wie temporärer Trockenheit, wird sich erhöhen. Besonders produktives Grünland benötigt aber eine ausreichende und regelmäßige Wasserversorgung während der Wachstumsperiode. Deshalb werden die Futterproduktion von Grünland, die Ertragsstabilität und der Futterwert von temporärer Trockenheit beeinflusst werden. Aus diesem Grund sind Anpassungsstrategien nötig, um eine zukünftige und nachhaltige Grünlandfuttererzeugung zu sichern. Erhöhte pflanzliche Biodiversität wird oft als Möglichkeit angesehen, Funktionen von Ökosystemen, wie Produktivität und Futterwert, im Grünland zu verbessern. Es gibt eine fortlaufende Diskussion wie eine erhöhte Artenzahl auf Stress, besonders Trockenstress, reagiert und wie dabei Produktivität, Futterwert und Wassernutzung beeinflusst werden. Andere Untersuchungen zeigten, dass Artidentität und die Zusammensetzung der funktionellen Gruppen wichtige Faktoren für Produktivität und Futterwert sind. Auf Grund dessen haben wir von Juli 2009 bis Juni 2011 ein Trockenstressexperiment in einer Vegetationshalle durchgeführt. Verschiedene temporäre Trockenstressereignisse wurden in drei Aufwüchsen in zwei Vegetationsperioden durchgeführt. Die klimatischen Verhältnisse in der Vegetationshalle folgten normalen saisonalen Verläufen mit Frost im Winter und höheren Temperaturen im Sommer. Trockenstress wurde induziert, indem, nach einer anfänglichen Bewässerung, die Wasserversorgung für einen bestimmten Zeitraum eingestellt wurde. Die Wasserverfügbarkeit des Bodens konnte dabei immer kontrolliert werden. Für das Experiment wählten wir ertragsstarke und landwirtschaftlich nutzbare Arten des Grünlands der gemäßigten Zonen aus. Die Arten wurden in Monokultur und Drei- sowie Fünfartenmischungen gesät und enthielten die funktionellen Gruppen Leguminose (Trifolium repens L.), Gras (Lolium perenne L., Dactylis glomerata L.) und Kraut (Plantago lanceolata L., Taraxacum officinale F.H. Wigg. agg.). Der von uns gewählt Umfang der Artenzahl zeigte schon in anderen Biodiversitätsexperimenten einen Einfluss auf die Produktion. Untersucht wurden die Effekte von Artenzahl und funktionellen Gruppen auf Ertrag, Ertragsstabilität, Wassernutzung und Futterwert (Rohprotein, wasserlösliche Kohlenhydrate, neutrale und saure Detergenzienfasern). Als Indikatoren für die Ertragsentwicklung und die agronomische Wassernutzungseffizienz (Verhältnis von Ertrag zu Wasserverbrauch) dienten der Stickstoffertrag und die Stickstoffkonzentration der Bestände sowie δ13C Signaturen, sowohl mit unlimitierter Wasserversorgung als auch mit Trockenstress. Überdies führten wir 2009 ein Kurzzeitfeldexperiment auf einem alten Grünlandbestand auf dem Versuchsgut der Universität Göttingen in Reliehausen durch. In diesem Versuch wurde ebenso der Einfluss von Trockenstress und Artenzahl auf den Ertrag und die Wassernutzung untersucht. Unsere Daten zeigten, dass Trockenstress die Produktivität verringert und die Wassernutzung beeinflusst, beides abhängig von der Stärke des Stresses. Bei moderatem Stress war die agronomische Wassernutzungseffizienz unverändert oder stieg leicht an, bei starkem Stress verringerte sie sich jedoch. Der Stickstoffertrag und die Stickstoffkonzentration waren brauchbare Indikatoren für die agronomische Wassernutzungseffizienz, wohingegen δ13C weniger geeignet war. Die agronomische Wassernutzungseffizienz wurde von Stickstoff erhöht. Es gab keinen oder nur einen sehr geringen Einfluss von Trockenstress auf den Futterwert. Saisonale Effekte hatten mehr Einfluss auf den Futterwert. Allgemein scheint der Ertragsrückgang wichtiger als die Veränderungen des Futterwerts zu sein. Die Artenzahl beeinflusste den Futterwert und die Ertragsstabilität über die Vegetationsperiode nicht. Mit Hilfe des “sampling effect“ (Probennahmeeffekt) können der manchmal positive Einfluss der Artenzahl auf den Ertrag und die agronomische Wassernutzungseffizienz und der Rückgang dieses Einflusses unter Trockenheit erklärt werden. Mit erhöhter Artenzahl stieg der Anteil der leistungsfähigen, aber trockenheitssensitiven Leguminose. Weiterhin gab es einen Hinweis, dass die Artenzahl die Geschwindigkeit des Wasserverbrauchs erhöht. Die Ergebnisse des Feldexperiments bekräftigten die Befunde bezüglich der Effekte des Trockenstresses, des Ertrages und der Wassernutzung. Aus diesen Gründen kann die „insurance hypothesis“ (Versicherungshypothese), die besagt, dass eine erhöhte Artenzahl Ökosystemfunktionen gegenüber Umweltveränderungen stabilisieren kann, nicht bestätigt werden. Jedoch waren die funktionellen Gruppen wichtige und bestimmende Faktoren der Leistung unter nicht Wasser limitierten Bedingungen und Trockenstress. Die Leguminose hatte besonders auf Ertrag, agronomische Wassernutzungseffizienz und Rohprotein einen positiven Einfluss, jedoch erhöhte sie auch den Wasserverbrauch und die saisonale Variabilität. Gräser stabilisierten den Ertrag und den Wasserverbrauch und erhöhten die wasserlöslichen Kohlenhydrate sowie die Faserfraktionen, während sie den Ertrag und die agronomische Wassernutzungseffizienz unter den stickstofflimitierten Bedingungen unseres Experiments verringerten. Die funktionelle Gruppe Kräuter zeigte ähnliche Ergebnisse bezüglich Ertrag und Wassernutzung, aber sie erhöhte das Rohprotein. Unsere Ergebnisse demonstrieren, dass die vorhergesagte Zunahme von Trockenstressereignissen die Produktion reduzieren und die Wassernutzung ändern wird. Änderungen im Futterwert werden dabei weniger wichtig als der Ertragsrückgang sein. Für die Produktion, die Wassernutzung und den Futterwert wird die Artenanzahl weniger relevant sein als die funktionelle Zusammensetzung von Grünland. Deshalb wird eine angepasste Grasnarbenzusammensetzung für die Sicherung der Produktion von wiederkäuenden Nutztieren unter den Bedingungen des erwarteten Klimawandels Bedeutung erlangen.

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Seither, Melanie. "The effect of grassland botanical composition and (co-) grazing cattle and sheep on herbage production and sward nutrient utilisation". Doctoral thesis, 2011. http://hdl.handle.net/11858/00-1735-0000-0006-AB38-F.

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Dickeduisberg, Michael. "Management and drought effects on growth and herbage yield of Tall Wheatgrass (Agropyron elongatum) for biogas production in Central Europe". Doctoral thesis, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E465-0.

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41

Sartie, Alieu Mortuwah. "Phenotypic assessment and quantitative trait locus (QTL) analysis of herbage and seed production traits in perennial ryegrass (Lolium perenne L.) : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy (Ph. D.) in Plant Science, Institute of Natural Resources, College of Sciences, Massey University, Palmerston North, New Zealand". 2006. http://hdl.handle.net/10179/1474.

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The aims of this study were to develop a genetic linkage map of perennial ryegrass, identify quantitative trait loci (QTL) for herbage and seed production traits, and to identify DNA markers associated with QTL for use in marker-assisted selection (MAS). Major traits identified for herbage production were leaf elongation rate (LER), leaf lamina length (LL), tiller number (TN) and tiller weight (TW), and for increased seed production were seed yield per head (SdYH), reproductive tiller number (RT), reproductive tillers with matured heads (TMH), florets per head (FH), spikelets per head (SH), florets per spikelet (FS), floret site utilization (FSU) and seed weight (TSW). A genetic linkage map spanning 582 centimorgans (cM) was constructed with EST-SSR (simple sequence repeat markers derived from expressed sequence tags) and used to identify QTL for herbage dry weight (DW) and seed yield per plant (SdYP), and their key component traits. Significant genotype by environment effects were encountered for herbage yield, with fewer QTL identified in spring than in autumn. For some traits, ranking of genotypes differed greatly between seasons and different QTL were identified. QTL for DW were identified on linkage groups (Lg) 1 and 6. The QTL on Lg 6 co-located with QTL for TN, while that on Lg 1 co-located with LER and LL. Markers at Lg 1 QTL (qDW-03-1.1) may be more useful for increasing herbage production by MAS because selection for high LER and long LL has been suggested to increase herbage production in perennial ryegrass. QTL for SdYP were identified on Lg 2 and Lg 6. The QTL on Lg 6 co-located with QTL for SdYH, FSU and TSW, while that on Lg 2 co-located with FH, SH and FS. For seed production, markers at Lg 6 QTL (qSdYP-03-6) may be very useful because this QTL co-located with QTL for SdYH, FSU and TSW, and SdYH has been identified previously as a key selection criterion for increasing seed yield. Marker-trait validation confirmed markers pps0495 and pps0698 identified by QTL analysis to be potentially useful for selecting for fast leaf appearance and long LL, respectively, in perennial ryegrass.

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Lee, Bo-Sian, e 李博獻. "Relation Between Chinese Herbal Medicine and Health and Liquid Organic Fertilizer Production". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/nwgcvc.

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碩士
國立嘉義大學
農藝學系研究所
106
The chinese herbal medicine is help for health and effective to cure disease, such as hypertension, headache, cough, scald, pain, sprain, stomachache, constipation and hurt. This study not only show curing of disease but also introduce maintaining of health by chinese herbal medicine. For example, Ophiocordyceps sinensis contains superoxide dismutase which can remove free radical, inhibit growth of tumor and increase immunity. Nothapodytes nimmoniana contains camptothecin which can inhibit growth of cancer cell. The chinese herbal medicine also help the growth of plant. The author founded his company in 2010 and invented the liquid organic fertilizer which was made of chinese herbal medicine. What’s more, the liquid organic fertilizer was passed the examination by executive yuan agricultural committee in the same year. And it was made all of chinese herbal medicine that didn’t add any chemicals. Its ingredients contain 1.5% of nitrogen, 1.2% of phosphoric anhydride, 1.0% of potassium oxide and 6.2% of organic matter. The liquid organic fertilizer has the positive regulation to plant growth.

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Li, Yi-Jing, e 李沂靜. "Effect of addition of Chinese herbal extracts on ACEI production by Antrodia cinnamomea submerged cultivation". Thesis, 2015. http://ndltd.ncl.edu.tw/handle/74359487347032462496.

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碩士
國立中興大學
化學工程學系所
103
Antrodia cinnamomea is an endemic species of fungi in Taiwan. Previous reports indicated that fruiting body of A. cinnamomea is characterized by varied physiological active compounds such as polysaccharrides, triterpenes, sesquiterpenes, and steroids et al, which proved to be effective for anti-oxidation, anti-tumor,anti-inflammatory, hepatoprotective and antihypertension treatments. Traditional Chinese herbs, such as Gastrodia elata, Mesona chinensis and Scutellaria baicalensis have been reported having the function of reducing blood pressure. In this project, the submerged culture of A.cinnamomea was carried out associated with the addition of these three Chinese herbal extracts, in order to elevate the ACEI activity of A.cinnamomea. In carbon source test, glucose gave had the highest biomass and ACE inhibition. In the nitrogen source test, yeast extract yeilded the highest biomass at eighth-day and peptone as nitrogen source produced the highest ACE inhibition, which was equal to 4929.5 ng captopril/L. The addition of Chinese herbal extracts to A.cinnamomea cultivation was conducted. The highest biomass had 13.59 gDW/L by adding 10g/L of Gastrodia elata ectracts. The highest ACE inhibition was equal to 8202.1 ng captopril/L by adding 10g/L of Mesona chinensis extracts, which was 3.2 times higher than the control test. However, the biomass and ACE inhibition were both decreased by adding different concentration of Scutellaria baicalensis extracts.

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44

Moremi, Mahlatse Ellias. "The improvement of bioethanol production by pentose fermenting yeasts previously isolated from herbal preparations, dung beetles and marula wine". Thesis, 2020. http://hdl.handle.net/10386/3392.

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Thesis (M.Sc. (Microbiology)) -- University of Limpopo, 2020
Production of bioethanol from lignocellulosic biomass has gained significant attention worldwide as an alternative fuel source for the transportation sector without affecting food supply. Efficient conversion of pentose sugars (L-arabinose and D-xylose) produced during hydrolysis of hemicellulose to ethanol can enhance the economic viability. In this study, a total of 390 yeasts isolated from Marula wine, the gut of dung beetles, herbal concoctions and banana residues were screened for the ability to ferment L-arabinose and D-xylose. Fourteen yeasts were able to ferment both pentose sugars and ten strains were subjected to an adaptation process in the presence of acetic acid using L-arabinose as carbon source. Four adapted strains of Meyerozyma caribbica were able to ferment L-arabinose to ethanol and arabitol in the presence of 3 g/L acetic acid at 35 °C. Meyerozyma caribbica Mu 2.2f fermented D-xylose, L-arabinose and a mixture of D-xylose and L-arabinose to produce 1.7, 3.0 and 1.9 g/L ethanol, respectively, compared to the parental strain with 1.5, 1.0 and 1.8 g/L ethanol, respectively, in the absence of acetic acid. The adapted strain of M. caribbica Mu 2.2f produced 3.6 and 0.8 g/L ethanol from L-arabinose and D-xylose, respectively in the presence of acetic acid while the parental strain failed to grow. In the bioreactor, the adapted strain of M. caribbica Mu 2.2f produced 5.7 g/L ethanol in the presence of 3 g/L acetic acid with an ethanol yield and productivity of 0.338 g/g and 0.158 g/L/h, respectively at a KLa value of 3.3 h-1. The adapted strain produced 26.7 g/L arabitol with a yield of 0.900 g/g at a KLa value of 4.9 h-1. Meyerozyma caribbica Mu 2.2f could potentially be used to produce ethanol and arabitol under stressed conditions.
National Research Foundation (NRF)

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45

Liao, Kuo-Chun, e 廖國淳. "Evaluation of optimal cultivation conditions on production of Hypericum perforatum L. and effects of manufacture processes on herbal tea quality". Thesis, 2017. http://ndltd.ncl.edu.tw/handle/14537830483701045771.

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碩士
國立中興大學
農藝學系所
105
Hypericum perforatum L. has been taken as experimental materials in this study to explore the effects of different cultivation densities, ratoon cropping at different temperatures, cutting cropping, and field tests on production efficiency of this important medicinal herb and the effects of different treatments of tea manufacturing processes on the herbal tea quality. Amounts of active ingredients in leaves of H. perforatum have been analyzed by high performance liquid chromatography (HPLC). Among 5 different treatments of cultivation densities (1-5 inches) of H. perforatum, the highest amounts of plant fresh weight (6.45 g) and fresh leaf weight (3.70 g) were obtained with 5 inches condition, whereas the highest amounts of investigated secondary metabolites in leaves were detected under the density of 4 inches. At 28 °C it reveals to be the better cultivation temperature for ratoon cropping of H. perforatum with faster growth and higher plant shoot. The higher amounts of hypericin, rutin and quercetin in leaves of St. John’s wort with ratoon cropping at 23 °C were detected as 0.023 mg g-1 FW, 0.78 mg g-1 FW and 0.15 mg g-1 FW, respectively. It shows that production efficiency of H. perforatum with ratoon cropping is better by the harvest interval of 2 and 3 months. This cropping model can be maximally harvested for 3 times. The content of detected active ingredients in leaves of H. perforatum would reduce to about 50 % of initial value when more than the harvest frequency. Through experiments of cutting cropping it can be observed that the faster growth, higher survival rate (>95 %) and higher contents of detected active compounds of H. perforatum would be the condition with cutting age of 8 months. The plant shoot production of H. perforatum under treatment with lengthening photoperiod (L : D=18 h : 6 h) mimicked to its natural condition has been found to be 4-fold higher than control in our preliminary field test. In the meanwhile, the phenomenon of flowering induction can be clearly observed. For investigated active ingredients of leaf, flower parts of H. perforatum in field, it exhibits that the contents of hyperforin, hypericin and melatonin are all higher in flower part, the contents of rutin are higher in leaf part under daylight-lengthening treatment and the contents of quercetin are not significantly different among treatments. During tea manufacturing investigations, the treatments of green tea manufacture process and control were detected with higher amounts of active compounds analysed in leaves of H. perforatum than black tea manufacture process. The only compound with lower level in green tea manufacture process is rutin. For black tea manufacture process, the contents of analysed active ingredients of H. perforatum would decline in proportion to fermentation time extention and temperature increase.

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46

Huang, Fu Hwa, e 黃復華. "Study on the Effect of Chinese Medicine Herbal Complexs on the Production of Egg with Low Cholesterol and High Phosphatidylcholine Contents". Thesis, 2014. http://ndltd.ncl.edu.tw/handle/21258512906168241090.

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碩士
國立臺東大學
生命科學系碩士班
102
Cholesterol and phosphatidylcholine in egg are important source of nutrition of chicken embryonic organ development. Cholesterol mainly for the body to vitamin D and a variety of steroid hormones and other important metabolic precursors, but too much can cause atherosclerosis, cardiovascular disease, stroke and diabetes. Egg is rich in various nutrients, but it is generally believed that a high level of cholesterol and dare not eat, so need to control appropriate lower cholesterol content in egg. Pho- sphatidylcholine has some protective effects of cardiovascular, neurodegenerative diseases, and physiological activity. In view of the current research on reducing cholesterol content of egg, to drop the use of cholesterol drugs or add a variety of minerals in the feedstuffs, often affect the chicken and human health, causing egg drug residue and chicken excretion and urine excretion of the metabolites of environmental pollution. Chinese herbal medicine when used correctly, has the multi-way, multi-organs and target pleiotropic effects and is not easy to produce drug resistance characteristics. In view of Chinese herbal medicine analysis method, in addition to the traditional five elements theory, can also use methods of modern scientific statistical analysis to study the effects of compound. The objective of the experiment was to use modern statistical analysis method in the analysis of compound Chinese medicine efficacy, and production safety, no drug residue and no pollution to the environment and health egg. The purpose of this study is to investigate the effects of different assembly of dietary Traditional Chinese Medicine herbs (TCM) for decreasing cholesterol and increasing phosphatidylcholine concentration of egg yolk in laying hens. Hyline laying hens of 35-week old were separated into 12 groups fed with basal feedstuffs and treatments with Astragalus membranaceous, Codonopsis tangshen Oliv, Acanthopanax senticosus, Angelica sinensis (Oliv) Diels, Epimedium grandiflorum Morr and Polygonum multiflorum Thunb by orthogonal t value design respectively. The experimental period lasted 5 weeks. Eggs and blood were collected for samples at end. Plasma and egg yolk contents of cholestrol and phosphatidylcholine were measured by Elisa assay kit. In egg yolk cholesterol, the results of experimental group by TCM compound was significantly lower than control group, and phosphatidylcholine was higher statistically significant (p<0.05). Triglyceride contents in egg yolk were no difference (p

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47

Liao, Tzumin, e 廖姿敏. "Study on the supplement of Chinese herbal medicine influencing the production of mycelial biomass and bio-active compounds by submerged culture of Phellinus linteus". Thesis, 2013. http://ndltd.ncl.edu.tw/handle/59539773669605968127.

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碩士
中州科技大學
保健食品系
101
Some studies showed the anti-tumor activities of Phellinus linteus on mice bearing with S180 tumor, H22 tumor and Lewis tumor. These resulted in increasing the requirement of P. linteus and fading fast of wild fruiting bodies. The cultivation time for artificial fruiting bodies was 6 to 8 months and the yield was low. Therefore, there is less contamination for submerged culture and short time for production of mycelial biomass. The research on the co-fermentation of Chinese herbal medicine and edible mushrooms to produce mycelial biomass and bioactive compounds is fewer. The goals of this study were that (1) the Chinese herbal medicine and the components for suitable medium were screened for the shaking-flask culture, and (2) the suitable fermentative conditions were for 5-L stirred-tank bioreactor. The results showed that the compositions of suitable medium for the production of mycelial biomass by shaking-flask cultures were medium volume 100 ml, inoculum volume 10%, glucose 3.0%, soypeptone 0.1% and Dioscorea opposita 0.5%, respectively. The maximun yield of mycelial biomass was 19.22 g/L. For the production of β-1,3-glucan by shaking-flask cultures, the suitable medium were medium volume 150 ml, inoculum volume 5%, lactose, soypeptone and Eleutherococeus senticosus 0.5%, respectively. The compositions of suitable medium for the production of TP and TEAC by shaking-flask cultures were medium volume 150 ml, inoculum volume 10%, glucose, tryptone and Ganoderma lucidum 0.5%, respectively. P. linteus was cultured in Dioscorea opposita medium by 5-L stirred-tank bioreactor to produce mycelial biomass, at the eighth day, the mycelial yield (8.08 g dry weight /L) at aeration 2.5vvm and agitation rate 150rpm was twice as that at aeration 1.0vvm and agitation rate 125 rpm. This indicated that the demand for the culture of P. linteus in Dioscorea opposita medium by 5-L stirred-tank bioreactor were the higher aeration rate and agitation rate than 2.5 vvm and 150 rpm to favor the production of mycelial biomass, respectively.

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48

BÁRTOVÁ, Eva. "Chov skotu v podmínkách ekologického zemědělství". Master's thesis, 2007. http://www.nusl.cz/ntk/nusl-46694.

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The diploma thesis is divided into three parts: cattle herd management, ethology and economic evaluation. The observation was carried out on the farm which is situated in the mountain region of Šumava mountain with decreasing agricultural production. The main production is cattle breeding without market milk production. These meat breeds (Hereford, Aberdeen angus, Charolais) are bred there.

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