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1

Svinurai, Walter. "Manure production and nutrient management in pasture-based dairy production systems." Thesis, University of Fort Hare, 2010. http://hdl.handle.net/10353/475.

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Manure production and nutrient management in pasture-based dairy production systems by Walter Svinurai The effect of dietary treatments on nutrient excretion was determined and an attempt to improving the retention of excreted nitrogen in stored manure using Aloe ferox leaf gel (AFLG) and pine bark was conducted at a pasture-based dairy farm. The animal mass-balance method was used to determine nutrient excretion by cows fed on three dietary treatments, Lolium perrene-based treatment (LP), Lolium multiforium-based treatment (LM) and Lolium perenne- Trifolium repens -based treatment (LTF). In separate experiments, slurry from dairy cows fed LM was amended with AFLG and pine bark at concentrations of 25, 50, 75 and 100 g/l and stored under anaerobic conditions for 16 days. The highest and lowest excretions of N, P and K were observed in LM and LP treatments, respectively. Increasing dietary N improved K and N retention in milk and, consequently increased milk urea nitrogen (MUN) and N excretion (P < 0.05). The concentrations of AFLG affected N and P retention in manure (P < 0.05). The highest retention in total Kjeldahl nitrogen (TKN) of the initial was 42% AFLG at 25g/l inclusion rate. Ammonium nitrogen (AMN) concentration increased significantly due to the interactive effect of AFLG inclusion rate and time. Pine bark powder significantly improved N and P retention in manure at all concentrations. The retention in TKN was higher (P < 0.05) at 25g/l pine bark powder than other concentrations. The interaction effect of inclusion rate and time increased iii AMN (P < 0.05). Dietary treatments significantly affected nutrient excretion, and AFLG and pine bark considerably improved N retention in stored slurry. Findings from the filed trial suggest the need for more attention on managing dietary nutrients in the post-rainy and cool-dry season when growth of pasture influenced choice of dietary treatments that led to high nutrient excretion. Field simulation of the additives to determine their efficacy and environmental hazards was recommended.
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2

Chiy, Paul Chu. "Sodium supply for pasture and dairy cow production." Thesis, Bangor University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.331954.

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3

O'Connell, Kathleen Ann. "Environmentally sustainable fertiliser nitrogen management practices for pasture production." Thesis, Queen's University Belfast, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426720.

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4

Mills, Annamaria. "Understanding constraints to cocksfoot (Dactylis glomerata L.) based pasture production." Phd thesis, Lincoln University. Agriculture and Life Sciences Division, 2007. http://theses.lincoln.ac.nz/public/adt-NZLIU20070717.161658/.

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This research examined the mechanisms by which temperature, water availability and nitrogen (N) affect the dry matter (DM) yield potential of cocksfoot (Dactylis glomerata L.) dominant pastures. The experiment was a split plot design with main plots of fully irrigated (I) or dryland (D), sub-plots of N fertiliser at 800 kg N/ha in 2003/04; and 1600 kg N/ha in 2004/05 (+N) or 0 kg N/ha (-N). The potential environmental yield of an established 8 year old cocksfoot dominant pasture was 21.9 t DM/ha/y from I+N pastures compared with 9.8 t DM/ha by I-N pastures and 15.1 t DM/ha/y by D+N pastures. The lowest yields were from dryland pastures with no N which produced 7.5 t DM/ha/y in 2003/03 and 5.0 t DM/ha/y in 2004/05. The effect of seasonal temperatures on the DM production, when periods of water stress were excluded, was quantified using thermal time accumulated above a base temperature of 3°C as 7.0 kg DM/°Cd/ha for N fertilised pastures and 3.3 kg DM/°Cd/ha for pastures with no N. The 2.5 t DM/ha difference in yields of D-N pastures in 2003/04 and 2004/05 was the result of the duration, extent and timing of the water stress period. In both years the critical limiting deficit (DL) was calculated as 78 mm from the soil moisture deficit in the 0-0.8 m soil layers. Beyond DL yield decreased at a rate of 1.45%/mm in +N and –N pastures, relative to fully irrigated control pastures. Yields of D+N and D-N pastures were similar during periods of water stress with 0.4±0.1 t/DM/ha produced during the rotation ending 30/12/2003. This was less than from either the I-N (1.2 t DM/ha) or I+N (3.5 t DM/ha) pastures due to the reduction in the amount of photosynthetically active radiation intercepted by the canopies of the dryland pastures. However, in the rotation ending 2/5/2004, after autumn rain alleviated drought conditions, yield of the D+N pasture was 2.1 t DM/ha compared with 1.7 t DM/ha by I+N pastures. The effect of N on yield was described using a nutrition index which showed that as DM yield increased N% in the herbage declined. This is a function of the ratio between metabolic and structural N requirements rather than caused by ontogeny alone. Specific leaf N was determined at two harvests and appeared constant at a given point in time (1.0-1.6 g N/m² leaf). In contrast, specific pseudostem N increased from 0.8-1.0 g N/m² pseudostem at an NNI of 0.4 in –N pastures to 2.6-3.0 g N/m² pseudostem at an NNI of 1.2 in the +N pastures. Differences between the yields of +N and –N pastures were caused by differences in radiation use efficiency (RUE) as determined by the linear relationship (R²=0.76) between RUE and the nitrogen nutrition index (NNI). In this thesis, empirical relationships for the effects of temperature, water availability and N were derived and the physiological mechanisms which underlie these descriptions were identified. These relationships provide clear and simple explanations of the effects of environmental variables on the productivity of cocksfoot based pastures which will enhance understanding of the benefits and limitations of cocksfoot, particularly in dryland farming systems.
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5

Benedict, Katherine A. "Modelling applications to pasture-based beef production in Atlantic Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ49312.pdf.

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6

Emenheiser, Joseph Carl. "Economic Pasture-Based Cow-Calf Systems for Appalachia." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/24787.

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Pasture-based beef production is well-suited for the Appalachian region of the United States. This research investigated pasture, beef cattle, and economics components within the cow-calf sector of pasture beef production, and presents implications of their interplay for the vitality of the whole system. Samples of forage DM mass and CP, ADF, NDF, and ash contents in each paddock of a rotational stocking system were collected monthly for 4 grazing seasons. Effects of month, stockpiling, hay feeding, temperature, precipitation, and durations of paddock grazing and rest on forage mass and quality measurements were investigated. The system was complex and dynamic; precipitation and rest days in particular showed clear interactions with both month and stockpiling when predicting forage mass and quality. Available DM, TDN, and CP were compared to nutrient density requirements for beef cows to conclude that the system met or exceeded requirements. Six years of production data from a spring-calving cow-calf enterprise that utilized rotational stocking and fall stockpiling were analyzed. Comparisons among 2 cow frame size and 2 calf creep system treatments for production efficiency (total weaning weight per land area), and net returns to the enterprise, were made. Pastures with medium frame cows and designated creep systems had the greatest production efficiency, but also had the highest costs and netted the least returns. Greatest net returns were achieved in large frame, forward creep systems, which had the lowest production efficiency but also the lowest costs. Provided the quality of calves produced is suitable for other phases of the production stream, we conclude that minimizing costs rather than maximizing productive outputs is a better focus for cow-calf enterprises faced with similar decisions among frame size and creep system treatments.
Ph. D.
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7

Groover, Gordon E. "Financial Performance of Pasture-Based Dairies: A Virginia Case Study." Diss., Virginia Tech, 2001. http://hdl.handle.net/10919/27038.

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Virginia dairy producers are considering intensive grazing as a profitable and ecologically viable alternative to confinement dairy production. The objective of this study is to compare financial performance for pasture-based dairy farms relative to similar resourced-based confinement farms. Comparisons are based on the recommended financial and profitability measures of performance provided by the Farm Financial Standards Council. Primary and secondary data plus simulation of daily pasture supply and animal demands are used to develop 100 and 200-cow farms with a land base representative of the Ridge and Valley regions of Virginia. Representative farms were developed to explore financial performance based on the intensity of pasture use, from total confinement to seasonal farms using intensive grazing (in which pasture, hay, and energy supplements are the only sources of nutrients for all dairy animals on the farm). Results of the analysis demonstrate that pasture-based seasonal production is more profitable and has a higher level of repayment capacity and financial efficiency than all other production systems in this study. Greater financial performance by the seasonal farms is obtained even though such farms obtain lower average annual milk prices and 10 percent less milk sold per cow than the similar confinement farms. Pasture-based farms that feed a partial total mixed ration during the summer (25 percent of ration dry matter and 45 percent of ration dry matter from pasture) have fewer financial advantages than the seasonal farms. However, their performance exceeds that of the confinement farms and intensive pasture-based farms milking year round. The intensive pasture-based farms milking year round are the poorest financial performers. Additional conclusions for this study are: 1) the 100-cow farms exhibit insufficient financial performance to provide for family living, debt service (at 40 percent debt to equity ratio), and a cushion for events such as droughts or declines in milk prices; and 2) financial performance of the 200-cow dairies is better, yet the added income from a member of the farm having off-farm income will provide a cushion against unforeseen production and financial risks. Follow up research should address the interface of three issues; stocking rates, farm profitability, and environmental compliance.
Ph. D.
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8

Fore, Steven R. "Confinement vs. pasture : an economic and environmental comparison of swine production systems /." Available to subscribers only, 2006. http://proquest.umi.com/pqdweb?did=1136078011&sid=17&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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9

Maddern, Rowan John. "Low water-soluble superphosphate fertiliser for pasture production in south-western Australia." Thesis, Curtin University, 2016. http://hdl.handle.net/20.500.11937/2242.

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Single superphosphate is derived from chemically treating rock phosphate into relative proportions of monobasic, dibasic and tribasic calcium phosphate to produce a commonly used source of phosphorus fertiliser for pasture systems. The leaching of phosphorus on susceptible soil types contributes to eutrophication and environmental damage. By modifying the chemistry of single superphosphate to match a soils phosphorus binding index and rainfall conditions, pasture dry matter yield can be maintained and leaching of phosphorus significantly reduced.
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10

Sangha, Kamaljit Kaur, and Kamaljit kaur@jcu edu au. "Evaluation of the effects of tree clearing over time on soil properties, pasture composition and productivity." Central Queensland University. School of Biological and Environmental Sciences, 2003. http://library-resources.cqu.edu.au./thesis/adt-QCQU/public/adt-QCQU20060921.115258.

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Tree clearing is practised for greater beef production and hence monetary gains from grazing systems of central Queensland. The high rates of clearing in the past and even recently (577, 000 ha/yr during 1999-2001) were mainly to develop land for pastures. The sustainability of cleared pasture systems over the long-term is questioned. Three major types of tree communities i.e. Eucalyptus populnea F. Muell., E. melanophloia F. Muell. and Acacia harpophylla F. Muell. ex. Benth. were selected on one property in central Queensland to quantify the impacts of clearing on pasture production and composition, and soil properties. The impacts were measured over time-since-clearing (recent (<5 years), medium (11-13years) and old (>30 years)) in unreplicated cleared pastures in comparison to their replicated uncleared/intact woodland pastures of each tree community. Measures of pasture above-ground biomass production on a single property over time-sinceclearing in cleared systems showed that gains were not sustained over the long-term. The difference in response to clearing between tree communities was evident and important to support the future policy decisions. The impact of clearing on soil properties (physicochemical and biological) was confirmed, and explained the lesser availability of nutrients with time of clearing in cleared pastures. The changes in some soil properties underscored the associated risks and changes in ecosystem functions due to clearing. Less litter was produced at cleared than uncleared pastures, but nutrient release was faster at cleared compared to uncleared systems. The overall effect of clearing in terms of pasture and litter production, and major soil parameters were analysed using multivariate analyses.
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11

Smith, Steven Murray. "Assessing variability in the production of pasture using GIS and remote sensing techniques." Thesis, University of British Columbia, 1988. http://hdl.handle.net/2429/29293.

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Information relating to the spatial characteristics of biophysical resources has been difficult to incorporate into land management. In this study statistical analysis was used to demonstrate that forage yield and quality were influenced by the water balance and soil physical properties. Traditional empirical modelling techniques were of limited utility as predictors of yield and quality. However, multivariate statistical techniques provide predictor variables for individual forage cuts but not for a complete growing season. GIS provided several distinct advantages over traditional statistical techniques. First, it provided techniques to interpolate point data (such as forage yield and quality variables), and provide spatial distributions for a wide number of biophysical properties. Secondly, overlaying forage variables such as yield with a digital elevation model in a categoric manner provided output displaying the spatial relationships between the variables. Relationships derived from overlays using elevation and water retention properties provided good spatial predictions for several forage variables. Thirdly, digitized colour-IR aerial photographs were incorporated into the GIS where the pixel information was combined as map overlays via a regression equation. The resulting output provided very accurate spatial predictions for forage yield and quality parameters. Finally, economic data was generated in a spatial context and the resulting display was used to assess the effects of irrigation and management on forage yield and quality. The results suggest that the GIS techniques combined with remote sensing and economic data offer exciting possibilities to model and present spatial data.
Land and Food Systems, Faculty of
Graduate
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12

Cardoso, Abmael da Silva. "Greenhouse gas emissons and N2O mitigation in beef cattle production on tropical pasture /." Jaboticabal, 2016. http://hdl.handle.net/11449/135851.

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Orientador: Ana Cláudia Ruggieri
Banca: Carlos Eduardo Pellegrino Cerri
Banca: Patrícia Perondi Anchão de Oliveira
Banca: Ricardo Andrade Reis
Banca: Mara Cristina Pessoa da Cruz
Resumo: Metano (CH4) e óxido nitroso (N2O) são dois dos mais importantes gases de efeito estufa emitidos pela pecuária. Eles são produzidos pelas excretas dos animais e fertilizantes. No Brasil, a quantidade emitida destes gases e opções para mitigação foram pouco exploradas. Uma sequência de 4 experimentos foram realizados em campo (em duas estações chuvosas e duas secas, 106 dias de duração cada) com o objetivo de quantificar as emissões de N2O e CH4, volatilização de NH3 e o fator de emissão (FE) quando aplicadas fezes, urina, fezes + urina e fertilizante ureia em Latossolo Vermelho cultivado com capim-marandu. Investigou-se o efeito da umidade do solo e compactação, composição da urina, volume urinário, e adição de fezes sobre as emissões de N2O em um Latossolo recebendo urina manipulada em condições controladas, bem como nas emissões de CH4. Como opção para mitigar as emissões de gases de efeito estufa (GEE) foram estudadas as variáveis como as alturas de pastejo que afetam a magnitude das emissões de GEE; a influência estacional na produção e consumo dos GEE; quais são as variáveis chaves associadas com as emissões de GEE em pastagens de capim-marandu. Adicionalmente, investigou se o efeito dietético dos níveis do sal mineral na concentração de N na urina, o volume urinário, a proporção dos compostos nitrogenados na urina e a concentração de N nas fezes em condições de campo. Os FEs de N2O quantificados diferiram de acordo com a excreta e estação do ano. O FEs foram 2,34%, 4.26% e 3,95% na estação chuvosa e 3.00%, 1.35% e 1.59% na estação seca, respectivamente, para fezes, urina e fezes + urina. O FE do fertilizante ureia foi 0,37%. As emissões médias do CH4 acumuladas foram 99,72, 7,82 e 28,64 (mg C-CH4 m2) para fezes, urina e fezes + urina nesta sequência. Quando manipuladas as condições do solo como umidade, compactação e adição de...
Abstract: CH4 and N2O are two of the most important greenhouse gas emitted by livestock. They are produced from animal excretes and the fertilizer. In Brazil the amount and options to mitigate these gases are little explored. We carried out a sequence of 4 field-trials (two rainy and two dry season, 106 days each) aimed to quantify the N2O and CH4 emissions, NH3 volatilization and emission factor (EF) after application of dung, urine, dung + urine and urea fertilizer on a Ferralsol of a marandu palisade-grass pastureland of Brazil. We aimed to investigate the effects of soil moisture, soil compaction, urine composition, urine volume, and dung addition on N2O emission from a urine-treated tropical Ferralsol under controlled conditions as well on CH4 emission. As option to mitigate greenhouse gas (GHG) emissions we studied how grazing heights affect the magnitude of GHG emissions; how season influence GHG production and consumption; what are the key driving variables associated with GHG emissions. Additionally, we investigated the effect of dietary mineral salt levels on urine-N concentration, urine volume, the proportion of N compounds in the urine and faeces-N concentration under field conditions. The emissions factor (EF) calculated differed according excretes and season. The EFs were 2.34%, 4.26% and 3.95% in the rainy season and 3.00%, 1.35% and 1.59% in the dry season, respectively, for the dung patches, urine patches and dung + urine. The N2O EF from urea was 0.37%. The averages of CH4 accumulated emissions were 99.72, 7.82 and 28.64 (mg CH4-C m2) for dung, urine and dung + urine in this sequence. The manipulated soil conditions moisture content, compaction, and dung addition affected N2O emissions when varying quantities of urine-N were applied (in equal urine volumes) being higher when added dung and did not affect when varying urine volumes were applied (containing equal quantities of urine-N) ...
Doutor
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13

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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14

Batalha, Camila Delveaux Araujo. "Grazing strategies, animal performance and environmental sustainability in intensive pasture-based milk production systems." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-15032019-125835/.

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In Brazilian livestock, and its diverse ways of production, the management of grazing animals is known as the lowest return on investment on land use opportunities. Nevertheless, among different types of milk production systems, it is noted that the use of pasture grazing is a common feature between them. Thus, to achieve profitability and maintain system sustainability, the identification of the most adequate and efficient pasture management practices, can maximize production per cow and production per unit area. The low efficiency of this method of production, also classifies the national livestock as the major source of environmental pollution due the emission of pollutants, such as greenhouse gases and nitrogen. The adoption of pasture management techniques respecting forage physiological limits and increasing digestibility of nutrients, can reduce the excretion of nutrients and the production of methane per kilo of milk produced on the environment. The objectives of this thesis were to investigate metabolic variables, greenhouse gas emissions and animal performance for dairy cows grazing elephant grass subjected to rotational stocking strategies. Chapter 1: In this study was to evaluate two strategies of grazing management: pre-grazing targets of 95% versus maximum canopy light interception (LI). In intensive pasture-based milk production systems, the management based on LI95% allows lactating cows to have access to pastures with lower proportion of stems, with higher proportions of young leaves better chemical composition and perform an efficient grazing with lower forage losses. Therefore, the LI95% pasture management strategy results in higher energy intake, higher milk production per cow, higher stocking rates of pasture and higher milk yield per area. Also, the strategy allows the decrease of methane emissions per net energy intake when comparing to management based on LIMax. However, dietary N use efficiency did not increase with this management practice. Chapter 2: The objective of the second study was to evaluate the effects of paddock allocation time (a.m. vs. p.m.) on milk production, ruminal variables and efficiency of N use of mid-lactation dairy cows. In intensive pasture-based milk production systems, allocating cows on new paddocks on p.m. time has no effect on forage intake and milk production of grazing mid-lactation cows. However, the higher content of nonstructural carbohydrate of forage from p.m. pastures increases the yield of microbial protein, decreases milk urea nitrogen and tends to increase the yields of milk protein and milk casein compared to a.m. pastures. Throughout this thesis there were an improvement on nutritive value of forage adopting LI95% as a pre- grazing target and forage grazed at p.m. Therefore, the time of allocation on paddock should be used along with LI95% as fine-tune in intensive pasture-based milk production systems.
No Brasil, a produção animal em pastagens é reconhecida por ser uma atividade pouco competitiva frente a outras oportunidades de uso da terra. Embora sejam inúmeros os tipos de sistemas de produção de leite no Brasil, nota-se que a utilização de pastagens é característica comum. Assim, a identificação de práticas adequadas e eficientes de manejo do pastejo contribuirá com aumento da produção por vaca e por unidade de área, além de contribuir para a sustentabilidade do sistema. A baixa eficiência do uso dos recursos naturais tem classificado a pecuária nacional como uma importante fonte de poluição ambiental devido à emissão de poluentes, como gases de efeito estufa e excreção de nitrogênio. A adoção de técnicas de manejo de pastagens respeitando os limites fisiológicos da forrageira e aumentando sua digestibilidade, podem reduzir a produção de metano por quilo de leite produzido no ambiente e a excreção de nutrientes. Os objetivos desta tese foram investigar variáveis metabólicas e desempenho animal de vacas leiteiras em capim-elefante cv. cameroon submetido a estratégias de pastejo rotativo. Capítulo 1: Neste estudo foram avaliadas duas estratégias de manejo de pastejo: meta de pré-pastejo de 95% versus máxima interceptação luminosa (IL). Em sistemas intensivos de produção de leite à pasto, o manejo baseado no IL95% permite que vacas tenham acesso a pastos com maior relação folha: colmo, menores perdas de forragem, resultando em uma forragem com melhor composição química. Os animais pastejando forragem com IL95% tiveram maior consumo de matéria seca e energia, com maior produção de leite por vaca e taxa de lotação resultando em maior produção de leite por área. Além disso, a estratégia permite a diminuição das emissões de metano por consumo de energia líquida quando comparado a máxima IL. No entanto, a eficiência do uso de N não aumentou com essa prática de manejo. Capítulo 2: O objetivo do segundo estudo foi avaliar os efeitos do período de início pastejo (a.m. ou. p.m.) na produção de leite, variáveis ruminais e eficiência de uso de N de vacas leiteiras no terço médio da lactação. Em sistemas intensivos de produção de leite à pasto, o pastejo de novos piquetes no período da tarde não teve efeito sobre o consumo de forragem e produção de leite de vacas no terço médio da lactação. No entanto, o maior teor de carboidratos não fibrosos da forragem ao final do dia possibilitou o aumento da síntese de proteína microbiana, redução do nitrogênio uréico no leite e apresentou tendência para aumento da produção de proteína e caseína do leite em comparação à vacas que iniciaram o pastejo no período da manhã. Ao longo dos estudos desta tese houve uma melhora no valor nutritivo da forragem adotando IL95% e da forragem pastejada no período da tarde. Assim, o pastejo no período da tarde deve ser adotado juntamente com IL95% como ajuste fino em sistemas intensivos de produção de leite à base de pasto.
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Lasley, Peter Wallace. "Corn distillers dried grains with solubles supplementation in a pasture-based beef production system." [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1473228.

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16

Leech, Fiona. "Influence of alternative fertilizers on pasture production, soil properties and soil microbial community structure." Thesis, The University of Sydney, 2019. https://hdl.handle.net/2123/21460.

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Alternative fertilizers are commonly promoted for use on pastures to improve productivity and support a more ‘healthy’ soil microbial environment. However, minimal field research has been conducted to validate such claims. A 6-year study (2009–14) was conducted on phosphorus (P) deficient soils at three sites near Yass, NSW, to investigate the effect of top-dressing native perennial grass-based pastures with a range of alternative fertilizers and with single superphosphate (SSP). The alternative fertilizers included manures, composts, concentrated ash, crushed rock, rock phosphate-derived and microbial products. Annual measurements were made of soil chemical properties, pasture yield and botanical composition as well as relative effectiveness of products per unit of pasture grown. Soil microbial community structure was also analysed in the sixth year. Fertilizers with large quantities of P resulted in higher pasture production and clover content compared to the unfertilized control. Their cost-effectiveness in relation to pasture growth varied considerably and was a function of rate and frequency of application as well as amount and solubility of P applied. Despite large differences in pasture growth across the fertilizer treatments, there was no effect on microbial community structure compared with either the SSP or unfertilized controls. The observed variation in bacterial, fungal and archaeal community structures across all treatments was best explained by soil pH or aluminium concentration, which was influenced differentially by the fertilizer products. Fungal community structure was also correlated to pasture productivity parameters (i.e. pasture yield, clover percent and soil available P). These findings reveal a highly resilient soil microbial community influenced minimally by use of the alternative fertilizers, highlighting that on-farm management decisions regarding fertilizer product choice should primarily focus on pasture response and cost-effectiveness.
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Ennos, E. D. "An investigation of effects of management, plant selection and growth regulators on seed production of white clover (Trifolium repens L.)." Thesis, University of Newcastle Upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374753.

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Arney, David Richard. "Dietary sodium and the production, health and behaviour of lactating dairy cows." Thesis, Bangor University, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311483.

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Pereira, Igor Daniell Costa. "Economic values for production traits of Morada Nova meat sheep in a pasture based production system in semi-arid Brazil." Universidade Federal do CearÃ, 2010. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=16343.

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FundaÃÃo de Amparo à Pesquisa do Estado do CearÃ
The economic values for traits of a meet sheep production system were calculated using Morada Nova hair sheep, raised under the conditions of native pasture in the Brazilian semi-arid region, as model. These economic weights were estimated using the equation of profit, profit = revenue â costs, after increase by one unit and 1% for each trait, evaluated on the average of the others. Whereas 1% increase in the trait, the economic values for lambing percentage (LP), litter size (LS), lambs mortality (LM), yearling mortality (YM), ewes and rams mortality (AM), female slaughter weight (FSW), male slaughter weight (MSW), ewe adult weight (EAW), ram adult weight (RW), carcass yield (CY), number of lambings per year (NLY), age at first lambing (AFL) and number of anthelminthic doses used per year (AC) were 1,439, 1,439, -0,254, -0,110, -0,054, 0,487, 0,767, -0,172, 0,005, 1,523, 1,439, -0,258 and -0,025, respectively, expressed in Brazilian currency (R$) per ewe per year. The traits that showed greater economic importance were CY, NLY, LP and LS. The traits that showed lower economic values were: RW, AC and AM. The production system with Morada Nova sheep grazing native âcaatingaâ pasture in Brazilian Northeast, exclusively for meat production, is profitable when taking into account all costs of production, including that of family labour. Carcass yield was shown to be an important selection objective. As it is expressed when the animal is slaughtered, further studies need to be carried out with this population to aid in the choice of appropriate selection criteria for the improvement of this trait.
Os valores econÃmicos para caracterÃsticas de produÃÃo de carne de ovinos foram calculados considerando-se como modelo o sistema de produÃÃo com a raÃa Morada Nova, criada sob as condiÃÃes de pastagem nativa do semi-Ãrido brasileiro. Os ponderadores econÃmicos foram estimados utilizando a equaÃÃo de lucro, lucro = receita - custos, para aumento de uma unidade e de 1 % em cada caracterÃstica, avaliada no valor mÃdio das demais. Com o aumento de 1% nas caracterÃsticas (R$ por ovelha ano) os valores econÃmicos para fertilidade ao parto (FP), prolificidade (PRO), mortalidade de cordeiros (MC), mortalidade de borregos (MB), mortalidade de ovelhas e carneiros (MA), peso de fÃmeas ao abate (PAF), peso de machos ao abate (PAM), peso maduro das matrizes (PM), peso dos reprodutores (PR), nÃmero de partos/ano (NPA), idade ao primeiro parto (IPP), rendimento de carcaÃa (RC) e nÃmero de tratamentos parasitÃrios/ano (TP) foram 1,439, 1,439, -0,254, -0,110, -0,054, 0,487, 0,767, -0,172, 0,005, 1,523, 1,439, -0,258 e -0,025, respectivamente. As caracterÃsticas que apresentaram maior importÃncia econÃmica foram RC, NPA, FP e PRO. As caracterÃsticas que apresentaram menor peso econÃmico foram: PR, TP e MA. O sistema de produÃÃo com ovinos Morados Nova em pastagem nativa (caatinga) no Nordeste brasileiro, exclusivamente para a produÃÃo de carne, Ã rentÃvel quando se toma em conta todos os custos de produÃÃo, incluindo o de mÃo de obra familiar. O rendimento de carcaÃa foi mostrado a ser um objetivo importante seleÃÃo. Como ela se expressa quando o animal for abatido, estudos adicionais necessitam de ser realizadas com esta populaÃÃo para ajudar na escolha adequada de critÃrios de seleÃÃo para a melhoria desta caracterÃstica.
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20

Cooke, Andrew. "The management of UK pasture-fed beef production systems and impacts on dung and disease." Thesis, University of Bristol, 2018. http://hdl.handle.net/1983/1d9548c6-dc7c-4e33-952c-9d008862ca42.

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This thesis places dung firmly at the centre of livestock farming. It tests the overarching hypothesis that intentional management of dung as a critical resource on-farm has multiple benefits that improve the resilience of beef production systems. Dung is a primary resource in beef production systems. This importance of dung as an organic fertiliser that recycles nutrients in agricultural systems is widely recognised and understood. The connection between disease, dung and its management through diet choice for beef cattle has received far less attention. In this study, the cattle diet, both intake and forage management, significantly influenced the rate of bulk and biochemical (fibre fractions, protein, lipids, carbohydrates, organic matter, ash and micronutrients) dung degradation over 84 days under three forage management treatments on the North Wyke Farm Platform. Site-specific factors were the primary drivers of bulk dung degradation; 70% of degradation was driven by field site and 4% by dung type. Non-target impacts of anthelmintics pose a risk to dung fauna that moderate dung degradation. A multiple-regression model predicted that targeted selective treatments (TST) created refugia for dung-breeding fly Scathophaga stercoraria and that proportions of treated cattle (55%) was more influential than effective dung drug concentrations (13%). Effective TST programmes rely on practical diagnostic tools. A non-invasive protocol was developed for the quantification of immuno-markers (immunoglobulins and lactoferrin) in dung for gastrointestinal health assessment. The anecdotal benefits of increasingly popular 'mob grazing' were supported by case studies of factors including pasture performance, reduced gastrointestinal nematode (GIN) burden, and soil organic matter content over a grazing season in a UK-wide study. The conclusion of this multidisciplinary study is that dung management has a critical role to play in a systems-level understanding of beef production and that optimisation relies on a quantitative understanding of the relationships between wider biological processes on farms.
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21

Goni, Sindisile. "Production and reproduction performance of Jersey and Fleckvieh × Jersey cows in a pasture-based system." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86433.

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Thesis (MScAgric)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Genetic selection for high milk production, type and appearance for the last 50 years has suppressed secondary traits such as reproductive performance, productive life, health and survivability in the pure milk breeds. The economic importance of these secondary traits in dairy production systems is the basis for the interest seen in crossbreeding. The problem of growth rate of heifers, cow fertility, reduced disease resistance and small body frame for beef production in Jerseys can be improved by crossing Jerseys with dual purpose breeds, such as Fleckviehs which possess a more beef potential. Against this background, this study aimed at comparing the production and reproduction of Jersey and Fleckvieh × Jersey cows in a pasture-based system. Milk recording was done according to standard milk recording procedures. Milk production (milk, fat, and protein yield) was adjusted to 305 days of lactation and corrected for age at calving. Effects of breed, parity, month and year were estimated for milk, fat and protein yield as well as fat and protein percentage using general linear models procedure. The fixed effects identified as having significant effects on milk, fat and protein yield were breed, parity and year. F×J cows produced significantly more milk than J cows (6141 ± 102 vs. 5398 ± 95 kg milk). Protein and fat yield were significantly higher in F×J (201 ± 3 and 272 ± 4 kg, respectively) than in J cows (194 ± 2 and 246 ± 3 kg, respectively). There percentages of fat and protein differed slightly between the two breeds with the Jersey recording slightly higher percentages (4.61 ± 0.04 and 3.62 ± 0.03 %, respectively) compared to the F×J cows’ percentages, which were, respectively, 4.47 ± 0.04 and 3.51 ± 0.03 %. It was concluded that F×J crossbred cows were more productive than purebred J cows probably owing to heterotic effects. Heifers were inseminated at 13 months of age and cows 40 days post-calving. Using insemination records and pregnancy check results, fertility traits were analyzed and compared between the two breeds, using analysis of variance for continuous records. Conception age was the same for both breeds resulting in a similar age at first calving. For cows, the interval from calving to first insemination was significantly shorter (P <0.001) in crossbred cows being 76.7 ± 2.2 days compared to 82.4 ± 2.5 days for purebreds. A larger proportion (P < 0.001) of 0.70 for crossbred cows was inseminated within 80 days after calving compared to 0.54 for J cows. Although the absolute number of days between calving and conception (DO) was lower for F×J cows in comparison to J cows (104.8 ± 6.8 vs. 114.8 ± 8.1days, respectively), the difference was not significant. However, the proportion of F×J cows confirmed pregnant by 100 days in milk was 0.79, which was higher (P < 0.001) than the 0.66 for J cows. Results indicate the potential of improving reproductive performance of J cows through crossing with dual-purpose breeds. The beef production of purebred J and Fleckvieh x Jersey (F×J) bull calves was compared, where bull calves were reared similarly for veal, i.e. carcass weight not exceeding 100 kg, or as steers for beef to 21 months of age. In both the veal and steer production systems, the mean birth weight were higher (P < 0.001) for crossbred in comparison to J calves and steers (33.5 ± 1.2 kg vs. 27.9 ± 1.2 kg for veal) and (33.4 ± 0.9 kg vs. 26.9 ± 0.9 kg for steers) respectively. The live weight at 6 months of age was 163.5 ± 3.9 kg for J bull calves, which was lower (P < 0.001) than that for F×J bull calves (180.6 ± 4.0 kg). The F×J bull calves had a significantly higher average daily gain (ADG) of 0.82 ± 0.02 kg/day compared to 0.73 ± 0.02 kg/day for J bulls. Marketing age differed (P < 0.001) in the veal production system with F×J and J bull calves marketed at 7.1 ± 0.1 and 6.3 ± 0.1 months, respectively. End live weight at 21 months of age was significantly higher (P < 0.001) in F×J bulls (441.4 ± 14.9 kg) than the 322.6 ± 13.4 kg in J bulls; while ADG differed (P < 0.001) between the two breeds being 0.64 ± 0.02 and 0.46 ± 0.0 kg/day in F×J and J bull calves, respectively. Crossbred steers had a significantly higher carcass of 206.5 ± 8.9 kg compared to 157.9 ± 8.6 kg for J steers. Results indicate the potential of improving beef production characteristics of the J cattle through crossbreeding.
AFRIKAANSE OPSOMMING: Genetiese seleksie vir hoë melkproduksie, tipe en voorkoms die afgelope 50 jaar het sekondêre eienskappe soos reproduksie, produktiewe lewe, gesondheid en oorlewing onderdruk in die suiwer melk rasse. Die ekonomiese belangrikheid van hierdie sekondêre eienskappe in melkproduksie stelsels is die basis vir kruisteling. Probleme soos groei tempo van verse, koei vrugbaarheid, verlaagde weerstandbiedenheid teen siektes en klein liggaam raam vir vleisproduksie in Jerseys kan verbeter word deur die kruising van Jerseys met ' n dubbele doel rasse, soos Fleckviehs wat beskik oor beter vleis potensiaal. Teen hierdie agtergrond, is hierdie studie daarop gemik om produksie en reproduksie van Jersey en Fleckvieh x Jersey koeie in 'n weiveld - gebaseerde stelsel te vergelyk. Melk opname is gedoen volgens standaard melkaantekening prosedures. Melkproduksie (melk-, veten proteïen opbrengs) was aangepas vir 305 dae van laktasie en gekorrigeer vir kalf ouderdom. ‘n Algemene lineêre model was gebruik om die effekte van ras, pariteit , maand en jaar op melk-, vet- en proteïen opbrengs sowel as vet- en proteïen persentasie te bepaal. Die vaste effekte geïdentifiseer met 'n beduidende effek op melk-, vet- en proteïen opbrengs was ras, pariteit en jaar. F × J koeie het aansienlik meer melk as J koeie (6141 ± 102 teen 5398 ± 95 kg melk) produseer . Vet opbrengs was aansienlik hoër in F × J koeie as in J koeie (272 ± 4 246 teen ± 3 kg vet). Proteïen opbrengs was ook aansienlik hoër in F × J koeie as J koeie (201 ± 3 vs 194 ± 2 kg proteïen). Vet en proteïen persentasies het geneig om effens te verskil met 'n klein effek (4.61 ± 0.04 % vet en 3.62 ± 0.03 % proteïen) vir J koeie en (4.47 ± 0.04 % vet en 3.51 ± 0.03 % proteïen) vir F × J koeie. Daar is tot die gevolgtrekking gekom dat F × J gekruisde koeie kan meer produktief wees as suiwer J koeie weens heterotiese effekte. Verse kunsmatig geïnsemineer was op 13 maande ouderdom en koeie 40 dae na- kalwing aangehou was. Met behulp van bevrugting en swangerskap rekords, is vrugbaarheid eienskappe ontleed en vergelyk tussen die twee rasse, met behulp van ontleding van variansie vir deurlopende rekords. Ouderdom van bevrugting was dieselfde vir beide rasse wat in 'n soortgelyke ouderdomsgroep was by eerste kalwing. Vir koeie was die interval van kalf tot eerste inseminasie aansienlik korter (P < 0.001) vir kruisgeteelde koeie wat 76.7 ± 2.2 dae in vergelyking met 82.4 ± 2.5 dae suiwerrasse is. ‘n Groter proporsie ( P < 0.001) van 0.70 vir gekruisteelde koeie is binne 80 dae na kalwing geïnsemineer in vergelyking met 0.54 vir J koeie. Alhoewel die absolute aantal dae tussen kalwing en opvatting (DO) laer was vir F × J koeie in vergelyking met J koeie (104.8 ± 6.8 teen 114.8 ± 8.1dae, onderskeidelik), is die verskil nie betekenisvol nie. Maar die verhouding van F × J koeie wat swanger bevestig is met 100 dae in melk was 0.79, wat hoër was (P < 0.001) is as die 0.66 vir J koeie. Resultate dui daarop dat daar potensiaal is reproduktiewe prestasie te verbeter van J koeie deur kruisteling met 'n dubbel- doel rasse. Die vleisproduksie van suiwer J en Fleckvieh x Jersey (F × J) bulkalwers vergelyk. Die bul kalwers is soortgelyk grootgemaak vir kalfsvleis, d.w.s karkas gewig mag nie 100 kg oorskry as bulkalwers nie, en as osse vir vleis tot 21 maande oud. In die kalwers- en os produksie stelsels, was die gemiddelde geboorte gewig hoër (P < 0.001) vir die kruise in vergelyking met J kalwers en osse (33.5 ± 1.2 kg teen 27.9 ± 1.2 kg vir kalwers) en (33.4 ± 0.9 kg vs . 26.9 ± 0.9 kg vir osse) onderskeidelik . Die lewendige gewig op 6 maande ouderdom was 163.5 ± 3.9 kg vir J bulkalwers en was hoër (P < 0.001) vir F × J bulkalwers 180.6 ± 4.0 kg. Die F × J bul kalwers het 'n aansienlik ‘n hoër gemiddelde daaglikse toename (GDT) van 0.82 ± 0.02 kg/dag in vergelyking met 0.73 ± 0.02 kg/dag vir J bulle. Bemarkingsouderdom verskil (P < 0.001) in die kalf produksie stelsel met F × J en J bulkalwers bemark op 7.1 ± 0.1 en 6.3 ± 0.1 maande , onderskeidelik. Finale lewendige gewig van 21 maande oud was aansienlik hoër 441.4 ± 14.9 kg in F × J bulle as 322.6 ± 13.4 kg in J bulle , terwyl GDT hoër was (P < 0.001), met 0.64 ± 0.02 kg/dag en 0.46 ± 0.0 kg/dag in F × J en J bulkalwers, onderskeidelik. Gekruisde osse het 'n aansienlik hoër karkasgewig 206.5 ± 8.9 kg in vergelyking met 157.9 ± 8.6 kg van J osse. Resultate dui daarop dat daar potensiaal is om die beesvleis produksie-eienskappe van die J beeste te verbeter d.m.v. kruisteling.
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22

Fraser, Duncan. "The potential of kikuyu grasses [Cenchrus clandestinus] for turf and pasture production under environmental stress." Thesis, The University of Sydney, 2019. https://hdl.handle.net/2123/21968.

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Kikuyu [Cenchrus clandestinus (Hochst. ex Chiov) Morrone] is an important pasture and turf species in Australia. However, little is known of the extent of adaptation of this species to environmental stresses. Naturalized populations and commercially released genotypes were compared in managed greenhouse and field experiments to establish the breadth of responses to salinity and drought stress. The physiological responses of materials to both salinity and drought stresses were determined using the normalized difference vegetative index (NDVI). Macro and micronutrients were assessed on vegetative matter harvested from each treatment at different stages of development using an inductively coupled plasma mass spectrometer. Amino acid variation was assessed at the same time using a liquid chromatograph mass spectrometer. Genotypes were subsequently ranked for salinity tolerance and significant variation in response was observed. Genotypes varied in nutrient levels under salinity stress with more tolerant genotypes showing lower rates of Na accumulation. Physiological adaptations among tolerant materials included exclusion and compartmentalization of Na. Amino acid concentrations varied with increasing salinity stress. However, salinity tolerance per say could not be ascribed to changes in any specific amino acid. Differences among genotypes for response to drought were observed in the field based on NDVI assessment. A relationship between salinity tolerance and WUE was suggested by the superior performance of some genotypes under both stresses. This is likely contributed by the same mechanisms as a significant genotype x stress treatment interaction was observed for both salinity and drought. However, it is unlikely that superior performance under stress is a consequence of genotype potential in the absence of stress.
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23

Le, Roux Andries Abraham. "The effect of soil residue cover on medicago pasture establishment and production under conservation agricultural practices." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97055.

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Thesis (MSc)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: Annual medic pastures play an important role in conservation agriculture (CA) practices in the Western Cape, because of the beneficial role it plays in rotation systems and the fact that it can re-establish on its own. In the Overberg medic pastures are the main pasture short rotation crop, but farmers in recent years shifted away from including medics. This was due to unsuccessful re-establishment and a visible decrease in dry matter production. This trend started after CA practices were implemented for a few years. A field study conducted during 2013 investigated medic re-establishment and production following a wheat, barley, oat and medic pasture production year ( WM, BM, OM and MM) of which residues were left on the soil surface at different cover percentage levels (100%, 75%, 50%, 25% and 0%). The objective of this study was to determine what the effect of different amounts of residues was on annual medic re-establishment and production. Data from this study suggest that management of annual medic pastures should aim to re-sow the medic pasture if plant count drops below 78 pants per square meter. Weed management is of cardinal importance as it competes for resources, light and space and decrease medic pasture re-establishment and production. The data also indicates that the wheat/medic sequence is the best option when applying a short cash crop/annual pasture cropping system. Producers should manage their animals to ensure that a 50% to 75% cover is left on top of the soil following the grazing of residues during the summer months. The study in 2013 should have been replicated, but due to the low levels of re-establishment and production a decision was made to re-plant the trial sites. The field study conducted during 2014 investigated the medic/clover establishment and production following a re-plant. Medics were replanted following a W, B, O and M season, respectively. Residues again were manipulated to different cover percentages (100%, 75%, 50%, 25% and 0%). The objective was again to look at the amount and type of residues on medic/clover establishment and production following re-plant. Data from this study indicated that it might be advisable for annual medic/clovers to be re-sown after a cereal production year rather than a medic pasture year. With the production of medic/clover pastures not being affected by the residue cover percentage, a 100% residue cover following re-plant is best in rotations, if the optimal effect of CA wants to be observed. If animals are included in the production cycle, grazing of residues during summer months can occur until 50% cover is left. Soils will take longer to reach its potential, but by including animals the gross margin is more stable year on year. Two supplementary studies were conducted to investigate the germination of annual medics under controlled conditions. The objectives of the first supplementary study was to investigate the physical barrier effect of residues at different percentage cover (100%, 75%, 50%, 25% and 0%) and a possible allelopathic action from different types of residues (wheat, barley, oat and medic) on the annual medic cultivar Cavalier (one of the cultivars used during 2014 field re-plant). The different amounts of residue had no significant effect on percentage emergence of Cavalier. The 0% residue cover having the slightly higher germination could be because there are no physical obstructions preventing seedlings to establish. The different types of residue cover had no significant effect on the germination of annual medics, as the germination under wheat, barley, oats and medic residues did not differ from the control. The control had a slightly higher germination percentage (85%), while germination under residues was just below the recommended germination rate of 80-85%. This could be an indication of allelopathy from residues. The objective of the second supplementary study was to investigate the allelopathic effects of different residue leachates (wheat, barley, oat and medic) at different levels of concentrations (100% leachate, 75%, 50%, 25% and distilled water being the control) on Cavalier germination. The interaction between leachate type and concentration were significant. Low levels of leachate concentration did not have a significant impact on medic germination when compared between each other and the control. When the concentration percentage was increased differences were detected. Cavalier germination decreased drastically when medic leachate concentration increased, indicating allelopathic effects. Cavalier germination followed the same trend, just not as drastic, when wheat leachate concentration increased. This indicates that wheat could also have a negative allelopathic effect. With oat leachate Cavalier germination did not decrease except when 100% concentrate was used, which could indicate a small allelopathic effect. Cavalier germination following barley leachate showed no effect as concentration increased, even showing the odd increase. Depending on repeatability or follow-up studies of these experiments, data suggest that re-plant of medic pastures is beneficial if plant count drops below sustainable levels. Management of weeds during the medic pasture year improves production. Annual medic pastures should be re-planted following a cereal production year rather than a previous pasture year. Thus single medic rotations are preferred, for example WMWM rotation. Greater amounts of residues are beneficial for CA effects, but allelopathic effects of wheat and oat residues should be taken in consideration during re-establishment and residue levels should be lowered.
AFRIKAANSE OPSOMMING: Eenjarige medic weidings speel ʼn belangrike rol in bewaring landbou (CA) praktyke in die Wes Kaap, vanweë sy vermoë om jaarliks op sy eie te hervestig en sy voordelige rol in rotasie stelsels. Eenjarige medic weidings is tans die hoof kort rotasie gewas in die Overberg, maar boere is tans besig om dit uit die rotasie uit te sluit. Dit is as gevolg van lae hervestiging sowel as die opvallende afname in produksie. Hierdie waarnemings het na ʼn paar jaar na die toepassing van CA praktyke begin. Gedurende 2013 is daar ʼn veldstudie voltooi rakende medic weiding hervestiging en produksie wat na ʼn koring, gars, hawer en medic weiding produksie jaar volg (WM, BM, OM en MM). Gedurende die studie is stoppels by verskillende persentasie vlakke van bedekking op die grond gelaat (100%, 75%, 50%, 25% en 0% bedekking). Die doel van die studie was om die invloed van verskillende tipes en hoeveelhede stoppels op die hervestiging en produksie van eenjarige medic weidings vas te stel. Data van hierdie studie dui aan dat jaarlikse medic weidings so bestuur moet word dat medics in die Overberg area se plant telling nie laer as 78 plante per vierkante meter daal nie. Onkruid bestuur is van kardinale belang, omdat dit kompeteer met medics en veroorsaak ʼn verlaging in hervestiging en opbrengs. Data dui ook aan dat ʼn koring/medic stelsel die beste opsie is wanneer ʼn kort kontant gewas/eenjarige weiding gewas stelsel toegepas word. Produsente moet hul vee so bestuur dat ʼn 50 tot 75% stoppel bedekking gedurende die somer maande oorgelaat word na beweiding. Die herhaling van die 2013 veld studie was van plan, maar ag gevolg van lae hervestiging en produksie was die proef kampe oor geplant. Die veldstudie in 2014 was medic/klawer vestiging en produksie na herplanting ondersoek. Die medic/klawer saad is geplant na ʼn koring, gars, hawer en medic weiding seisoen onderskeidelik. Stoppels is weereens na verskillende bedekking persentasies verander (100%, 75%, 50%, 25% en 0% bedekking). Die doel was om te kyk wat die effek van verskillende tipes en hoeveelhede stoppels op eenjarige medic/klawer weiding is na herplant. Data wys dat medic/klawer weidings verkieslik herplant moet word na ʼn graan produksie jaar as ʼn medic weiding produksie jaar. Die medic/klawer weiding is nie geaffekteer deur die hoeveelheid stoppels op die grond oppervlakte nie, dus is ʼn 100% stoppel bedekking verkieslik vir optimale CA effekte. As diere in die sisteem teenwoordig is, kan stoppels bewei word gedurende die somer maande tot ʼn 50% bedekking bereik word. Grond sal langer vat om sy potensiaal te bereik, maar die jaarlikse bruto marge sal meer stabiel wees. Twee aanvullende studies is onderneem en ontkieming van eenjarige medics is ondersoek onder beheerde toestande. Die doelwit van die eerste aanvullende studie was om te kyk na die fisiese versperring effek van stoppels by verskillende persentasie bedekking (100%, 75%, 50%, 25% en 0%) en ʼn moontlike allelopatiese effek van verskillende tipe stoppels (koring, gars, hawer en medic) op die eenjarige medic kultivar Cavalier. Verskillende hoeveelhede stoppels het geen beduidende uitwerking op die vestiging van Cavalier gehad nie. Die 0% stoppel bedekking het ʼn effens hoër vestiging gehad. Dit kon wees as gevolg van geen fisiese versperring wat die saailing verhoed om te vestig nie. Die verskillende tipes stoppels het geen beduidende uitwerking op die ontkieming van eenjarige medics nie, die vestiging onder koring, gars, hawer en medic stoppels het nie statisties verskil van die kontrole nie. Die kontrole het wel ʼn effense hoër persentasie vestiging gehad (85%), terwyl die vestiging onder die stoppels onder die aanbevole koers van 80-85% was. Dit kan dalk ʼn allelopatiese effek van die stoppels aandui. Die doel van die tweede aanvullende studie was om die allelopatiese effek van die verskillende tipes stoppels (koring, gars, hawer en medic) by verskillende vlakke van konsentrasie (100%, 75%, 50%, 25% van die onverdunde loogsel en gedistilleerde water as kontrole) op Cavalier ontkieming. Daar was ʼn beduidende interaksie tussen tipe en konsentrasie loogsel. Met lae konsentrasie vlakke van loogsel was daar nie ʼn werklike impak op Cavalier ontkieming tussen die verkillende tipes en die kontrole nie. Slegs wanneer die konsentrasie persentasie verhoog is, is verskille waargeneem. Cavalier ontkieming het drasties af geneem soos die medic loogsel konsentrasie toegeneem het, wat ʼn negatiewe allelopatiese en verhoogde osmolaliteit effek wys. Cavalier ontkieming het dieselfde tendens gewys wanneer koring loogsel konsentrasie verhoog was, maar nie so drasties soos medic loogsel. Dit dui daarop dat koring ook ʼn negatiewe allelopatiese effek wys. Met hawer loogsel het Cavalier ontkieming slegs by die 100% konsentrasie pyl afgeneem, wat op ʼn lae allelopatiese effek dui. Cavalier ontkieming onder gars loogsel het geen verandering gewys as konsentrasies toegeneem het nie, en het selfs ʼn toename in ontkieming in party gevalle ondergaan. Afhangend van herhaling of op-volg studies van hierdie eksperimente, wys die data dat dit voordelig is om medic weidings te herplant as plant telling onder 78 plante per vierkante meter daal. Die bestuur van onkruid tydens die medic weidings jaar verbeter opbrengs. Eenjarige medic weidings moet herplant word na ʼn graan produksie jaar liewer as ʼn vorige weidings jaar. Medics moet dus in ʼn eenjarige rotasie stelsel wees, byvoorbeeld WMWM rotasie. Meer stoppels is voordelig vir CA promosie, maar allelopatiese stowwe van koring en hawer stoppels moet in ag geneem word en stoppels moet verlaag word vir hervestiging.
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24

Van, Wyngaard Josef de Villiers. "Effect of palm kernel expeller supplementation on production performance of Jersey cows grazing kikuyu/ryegrass pasture." Diss., University of Pretoria, 2013. http://hdl.handle.net/2263/41070.

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Ruminant feed supplements are price sensitive and are effected by the continuous fluctuation of other raw material feed prices. Therefore, improving the efficiency of production and reducing cost of supplement concentrates for dairy cows are becoming increasingly important both for the smallholder and commercial dairy farmer. This can be overcome by replacing expensive energy and protein feeds with cheaper by-products. During periods of high maize prices, replacing maize with lower cost high fibre by-products becomes an economically viable option. Palm kernel expeller (PKE) fits the profile of a low cost, high fibre by-product. The aim of this study was to determine the effect of different inclusion levels of PKE in dairy concentrates for Jersey cows on milk production, milk composition, body weight (BW) and body condition score (BCS) change, rumen parameters and in situ ruminal kikuyu/ryegrass pasture degradability of dry matter (DMd) and neutral detergent fibre (NDFd) as well as NDFd rate (NDF kd). The study was conducted at the Outeniqua Research Farm situated near George in the Western Cape and cows grazed high quality kikuyu/ryegrass pasture during spring. Forty eight multiparous high producing Jersey cows were blocked according to 4% fat corrected milk (FCM), days in milk (DIM) and lactation number and randomly allocated to three treatments (control, low PKE, and high PKE). The PKE inclusion level in the control, low PKE, and high PKE treatment concentrates was 0, 20, and 40%, respectively. The PKE replaced part of the maize and protein sources in the concentrate. Milk yield was recorded daily and milk composition was determined in two week intervals over a 60 d period, after a 21 d adaptation period. Additionally, eight lactating rumen-fistulated cows were randomly allocated to the control and high PKE treatment in a two period crossover design. Ruminal pH, volatile fatty acids (VFA’s), ruminal ammonia-nitrogen (NH3-N), and in situ ruminal kikuyu/ryegrass pasture DMd, NDFd and NDF kd were measured. Cows received 6 kg (as is) concentrate per day divided over two milking periods and strip grazed kikuyu/ryegrass pasture as one group. Milk yield and milk fat content did not differ (P > 0.05) between treatments and were 21.3, 21.3 and 20.7 kg/cow/d and 4.63, 4.65, and 4.66% for cows receiving the control, low PKE and high PKE treatments, respectively. Milk protein, milk urea nitrogen (MUN), BW and BCS did not differ (P > 0.05) between treatments. Total VFA’s, average ruminal pH, ruminal NH3-N, and in situ ruminal kikuyu/ryegrass pasture DMd and NDFd as well as NDF kd did not differ (P > 0.05) between treatments. The acetic to propionic acid ratio was, however, higher (P < 0.05) for cows supplemented with the high PKE treatment. It can be concluded that partial replacement of maize with 20 or 40% PKE in a lactating dairy cow concentrate did not affect milk yield, milk fat content, milk protein content, somatic cell count (SCC), BW, or BCS. Rumen fermentation was unaffected and a healthy rumen environment was sustained. The replacement of higher cost maize and soybean oilcake by a lower cost PKE decreased feed cost. It is however not recommended to include PKE at 40% in the concentrate due to the increased time spent by cows in the milking parlour and the low palatability of PKE, which could lead to the tendency of increased concentrate refusals. It can be extrapolated from the data obtained from this study that milk production will be sustained when PKE is fed to cows on pasture at 2.4 kg/cow/day.
Dissertation (MSc Agric)--University of Pretoria, 2013.
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Animal and Wildlife Sciences
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Bungenstab, Elias José Muntifering Russell Brian. "Productivity, nutritive quality and utilization of dallisgrass (Paspalum dilatatum) for beef cattle production as influenced by fertilization regime and grazing management." Auburn, Ala, 2009. http://hdl.handle.net/10415/1867.

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Janse, Van Rensburg Marjorie. "Nutritive value of tall fescue (Festuca arundinacea) established on rehabilitated mineland for grazing cattle." Diss., University of Pretoria, 2013. http://hdl.handle.net/2263/40338.

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Sustainable animal production on pasture planted on rehabilitated mine land will only be possible if the optimal stocking rate for animal and pasture production is determined. A grazing trial was conducted on tall fescue, established on rehabilitated mine land and irrigated with mine waste water. The aims of this study were to quantify: a) animal performance and nutritive value at different levels of nitrogen (N) fertilization during pasture establishment, and b) intake, animal performance (defined as average daily gain; ADG) and nutritive value when different stocking rates were applied. This study was done during two seasons: season one in winter (6 June -16 July 2008) and season two in spring (28 Aug – 6 Nov 2008). In terms of post mining land use this study supplied valuable information on potential livestock production. The higher level of N fertilization applied during the winter of 2007 at pasture establishment resulted in a significantly (P < 0.05) higher crude protein (CP) concentration a year later compared to the lower levels of N fertilization. During the winter grazing season the pasture contained an average of 83.4 g CP kg-1 dry matter (DM), 601.9 g NDF kg-1 DM, 6.2 g Ca kg-1 DM and 1.7 g P kg-1 DM, the average in vitro organic matter digestibility (IVOMD) was 642.2 g kg-1 OM and the average leaf: stem ratio was 88:12. The ADG of crossbred weaner calves grazing the low N fertilization (LN), low stocking rate (LS) paddock (229.1 g day-1) was significantly (P < 0.05) lower than the ADG of weaner calves grazing the LN, high stocking rate (HS) and the high N (HN), LS respectively. The ADG of the animals in the HN, LS paddock was 482.7 g day-1 and in the LN, HS paddock was 310.6 g day-1. The low ADG for the LS treatment was due to the low CP concentration of this paddock, with values as low as 55.1 g CP kg-1 DM recorded during the winter grazing period. Low pasture nutritive value during winter can potentially limit animal production.spring grazing season the pasture contained an average of 101.0 g CP kg-1 DM, 639.1 g NDF kg-1 DM, 8.9 g Ca kg-1 DM and 2.1 g P kg-1 DM. The average leaf: stem ratio was 85:15, IVOMD was 717.5 g kg-1 OM and effective DM degradability (in situ) was 56.1 %. The average OM digestibility estimated with the alkane method varied between 720.8 to 768.3 g kg-1 depending on the alkane used and weather a correction was made for the faecal recovery of the alkane used. On average the forage available in the paddock with the LS had a significantly (P < 0.05) higher CP concentration, leaf: stem ratio and IVOMD, with a significantly (P < 0.05) lower NDF concentration than the HS paddock. This is probably due to the fact that in the HS paddock forage with a high nutritive value was removed at a higher rate. Irrespective of the calculation used, digestibility calculated by the alkane method did not differ significantly (P > 0.05) between paddocks at any time period. The average intake in the paddock with medium grazing stocking rate (MS) was significantly (P < 0.05) higher than the average for the other paddocks. The paddock with the MS was managed to supply a pasture DM allowance of 2.5 % body weight (BW). The DM intake over the spring season was 2.2 % BW. The MS treatment supplied sufficient plant material without resulting in large accumulation of plant material. The ADG for the spring season was 110.5 g day-1 and averages for each paddock did not differ significantly (P > 0.05) from each other. During the
Dissertation (MSc Agric)--University of Pretoria, 2013.
gm2014
Animal and Wildlife Sciences
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Abdelsayed, Mary. "Quantitative Genetic Analysis of Extended Lactation and Lactation Persistency In Australian Dairy Cattle on Pasture Based Systems." Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/13994.

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In the Australian dairy industry, and in particular Victoria, there has been a shift away from seasonally concentrated calving patterns. Reasons for such a shift stem largely from improved feeding of cows with year round feed supplies, and the introduction of new germplasm from North American Holstein Friesian animals into some Australian dairy herds. Such impacts have resulted in an increase in the phenotypic and genetic potential of cows to produce more milk and be milked for longer than the standard 305 days under seasonal calving systems. The increase in high output cows has come at an associated cost with a national decrease in reproductive performance and many highly productive cows being prematurely culled for failing to get in calf. One strategy of interest to the dairy industry is for high-producing cows being mated out of season and then carried over and milked for an extra 6 months (18 month calving interval). In Australia this is regarded as the most optimal and economical method on pasture-based systems. Limited information was available about the potential for genetic improvement of extended lactation under the Australian dairy system, which led to the objectives of this thesis. A very large amount of data with over 158 million test-day records was available to examine the scope for genetic improvement in extended lactation in the Australian dairy industry. A data handling pipeline was developed to assist in analysing and editing large scale industry test day records. Variation in Australian dairy cattle in respect to their lactation curves over an extended lactation was explored and derived traits obtained that were then used in the genetic analysis using mixed model methodology. The Wood model was fitted to milk yield records divided into 8 random subsets of 1 million pure Holstein cows with 20 million test-day records. Two traits of interest, namely persistency and extended lactation, were quantified and relevant descriptive traits derived. Variation among cows in their ability to maintain high production over a longer period of time was evident and a representation of the shape of average lactation curves in Australian dairy cows was presented. Findings showed that milk production during the extended lactation phase (from day 305 to day 610 of lactation) was on average equivalent to 40% of the production of the first 305 days of lactation (standard lactation) with an average milk yield of 8,887 L over the extended lactation. In terms of lactation persistency, 50% of peak production is maintained up to day 305. Estimates of heritability for milk, fat and protein yield under extended lactation (0.09-0.06±0.004) and lactation persistency (0.06-0.1±0.004) were low, while the cows’ repeatability for extended lactation and lactation persistency milk traits (0.20) was higher by comparison. Such findings indicate the potential for early cow performance to be used as an indicator for a cow’s successive lactation performance. Extended lactation and lactation persistency were found to be highly correlated to each other (genetic 0.60-0.98 and phenotypic 0.68-0.93), but not with the other economically important traits of milk, fat and protein yield (-0.05-0.1). This suggests that selection for increased extended lactation will not adversely impact on economically important and highly selected traits, namely cumulative 305 day yields and the Australian Selection Index (ASI). Extended lactation measured as a standardised ratio trait automatically adjusts for high peak yield. Producers selecting on this trait do not favour selecting cows with higher peak yields yet maintaining peak production over another 300 days in milk. In addition, extended lactation can be incorporated with cumulative 305 day milk yields and lactation persistency in a selection index in a designed breeding program. Estimated breeding values (EBVs) were generated for extended lactation and lactation persistency for milk, fat and protein yields, to assist with the selection of cows and bulls. Genetic trends showed no change till early 1990, followed by a steady increase (1genetic SD) in EBVs for extended lactation characteristics in the last 20 years. This increase is potentially a reflection of the increased selection for milk production and introduction of new germplasm from North American Holstein Friesian cattle into Australian herds. The research presented in this thesis will provide the Australian dairy industry with the breeding tools to enable selection of bulls to produce cows that are best suited to extended lactation in pasture-based systems. It has also contributed to the understanding of the genetics of extended lactation and lactation persistency that can be applied to other breeds in the Australian herd, and opened avenues for genomic predictions for these traits.
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Soriano, Felix Diego. "Grazing and Feeding Management of Lactating Dairy Cows." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36896.

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Two studies were conducted during the grazing season of 1997. Study 1 consisted of three Experiments, and the objectives were to compare milk production and composition, body weight change and body condition score, and to determine time patterns of grazing between cows supplemented with different forms and amounts of corn. Also rumen fermentation parameters were measured in cows supplemented with two different types of corn. In study 2, milk yield was measured when grazing pasture was supplemented to lactating Holstein cows fed a typical TMR diet. Predominantly orchardgrass pastures with lesser amounts of white clover and Kentucky bluegrass were grazed during both studies. In Experiment 1, 36 Holstein cows were supplemented either with 6, 6, 6, or 4 kg/d DM of high moisture corn, coarsely ground corn, finely ground corn, or high moisture corn in two equal feedings, respectively. Milk yield was similar (30.3 kg/d) among treatments. Milk protein (2.97%) and MUN (14.7 mg/dl) did not differ among treatments. Body weight change and body condition score change were similar among treatments (23.1 kg and -0.24). During Experiment 2, four rumen-cannulated cows in mid-lactation were supplemented 6 kg/d DM of either coarsely ground corn or high moisture corn in two equal feedings. After the p.m. milking, ruminal pH was measured and rumen fluid samples were collected to determine ammonia N and VFA. While grazing, this was repeated at 0.5, 1, 2, 3,...8 h post-corn feeding (0 h). Ruminal pH was similar for both corn supplements and was lowest (5.9 and 5.8) at 5 and 8 h, respectively. Rumen ammonia N concentrations started to increase approximately 2 h after cows began grazing, reaching maximum levels 5 h later. In Experiment 3, the number of cows grazing, lying, or standing were recorded every half hour, for two consecutive days, while grazing. Cows grazed an average of 6.4 h/d, 4.1 h in the afternoon and 2.3 h in the morning. Similarity in milk production, milk composition, BW change, and BCS between treatments indicates that the quality and availability of pasture permitted equal response regardless of the type or amount of corn supplemented. Fifty four Holstein cows in mid lactation were used in Study 2. Cows were fed either a TMR diet only, or were fed TMR during half of the day (after the a.m. or p.m. milking according to the treatment) and supplemented with grazing pasture during the other half of the day. Milk production was slightly but significantly higher for cows on the TMR treatment (29.1 vs. 28.2 and 27.6). No significant difference between treatments was observed in FCM (27.7 kg/d), and milk fat (3.47) and protein percentage (3.23). While BW change did not differ among treatments (25.7 kg), body condition score increased more in cows fed only a TMR diet (0.14 vs. -0.06 and 0.01). The TMR intake was significantly different between treatments, being highest for cows on the TMR treatment and lowest for cows grazing after the p.m. milking (26.6 vs. 20.3 vs. 17.5 kg/d DM). Income over feed cost differed between treatments, and was approximately 15.3% higher for cows supplemented with high quality pasture during the afternoon compared to cows on TMR. Dairy farmers may obtain economical benefits by practicing this type of management during the grazing season with little effect on milk yield.
Master of Science
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Sanjari, Gholamreza. "Evaluating the Impacts of Time Controlled and Continuous Grazing Systems on Soil Properties, Surface Hydrology and Pasture Production in South-East Queensland." Thesis, Griffith University, 2010. http://hdl.handle.net/10072/367657.

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There is an increasing recognition of the importance of rangeland ecosystems as the source of water supply, wildlife habitat, recreation, carbon sequestration, and so forth, in addition to being a resource for animal production. Land holders and graziers are concerned about the decline in pasture productivity, as well as the environmental consequences of their practices. Continuous grazing practice has been largely documented to encourage selective grazing by animals, exposing desirable plant species to repeated defoliations as compared with less desirable or undesirable species that are usually ignored. Long term continuous grazing in rangelands ecosystems has also decreased the relative abundance of palatable plants, resulting in lower productivity. Surface soil compaction is often attributed to continuous grazing, due to trampling, lower infiltration, higher runoff and soil loss, as well as imbalanced distribution of urine and faeces across paddocks. Time- controlled (TC) grazing, which includes short durations of intensive grazing, followed by long rest periods, has been increasingly adopted by graziers around the world. It is believed that TC grazing reduces the negative effects of continuous grazing and increases pasture productivity. Although the new TC grazing system has received a high degree of acceptance amongst livestock producers over the last two decades, little research has been carried out to document the environmental consequences of such a grazing system. To address this issue, a comprehensive large scale field study was carried out on the effects of the two grazing management systems (continuous and time-controlled) on selected pasture attributes, soil characteristics, runoff and soil erosion from 2001 to 2006 on the grazing property, “Currajong”, in the south-east region of Queensland, Australia. The results obtained show a highly significant herbage accumulation of up to 150% under TC grazing in 2006 compared with the earlier results following the change from continuous grazing to TC grazing in 2001. In continuous grazing however no such a significant change was found over the course of the study. In line with the results of herbage cover, ground cover and residue also increased with time under TC grazing but not under continuous grazing.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
Griffith School of Environment
Science, Environment, Engineering and Technology
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Fitzgerald, Tracey. "The effect of long-term supplementation with biotin on lameness, milk production and reproductive performance in pasture fed dairy cows /." [St Lucia, Qld.], 2001. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe16283.pdf.

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Schneider, Stephan Felix Verfasser], Johannes [Akademischer Betreuer] Schnyder, and Gerhard [Akademischer Betreuer] [Bellof. "Carbon flow from pasture to milk : Carbon isotope analysis as a tool of authenticity testing and proof of origin for pasture-based milk production / Stephan Felix Schneider. Gutachter: Gerhard Bellof ; Johannes Schnyder. Betreuer: Johannes Schnyder." München : Universitätsbibliothek der TU München, 2014. http://d-nb.info/1065376391/34.

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Larsson, Evelina. "Grazemore DSS för att prediktera beteskvalitet för mjölkkor = The Grazemore DSS to predict the quality of pasture grass in dairy production /." Umeå : Sveriges lantbruksuniversitet, 2006. http://epsilon.slu.se/10286250.pdf.

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33

Provazi, Milena [UNESP]. "Avaliação de espécies de Paspalum sob pastejo." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/95218.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Universidade Estadual Paulista (UNESP)
O objetivo deste experimento foi verificar o efeito do pastejo sobre a produtividade e a persistência de três acessos de Paspalum. O experimento foi desenvolvido na Embrapa Pecuária Sudeste, localizada em São Carlos-SP, no período de janeiro a dezembro de 2005. Foram comparados três acessos de Paspalum (Paspalum guenoarum - BRA-006572, Paspalum malacophyllum - BRA-003077 e Paspalum sp. - BRA-011681) e duas testemunhas (Brachiaria decumbens e Paspalum atratum cv. Pojuca) quando submetidos a dois níveis de desfolha (1.500 e 3.000 kg MS/ha de resíduo pós-pastejo). O ensaio foi do tipo mob grazing, utilizando o método de pastejo rotacionado com 27 dias de descanso e 1 dia de ocupação (período das águas) e 55 dias de descanso e 1 dia de ocupação (período das secas). A taxa de lotação animal das parcelas foi ajustada de acordo com a massa de forragem disponível antes do pastejo e com o nível de desfolha previsto pelo tratamento. As variáveis foram: massa de forragem antes e após o pastejo; proporções de folhas, hastes e material morto; densidade de perfilhos; incidência de plantas invasoras; observações relativas à susceptibilidade a pragas e doenças, sintomas de toxidez e deficiência mineral. O Paspalum atratum mostrou características positivas de produção e persistência tanto na altura de pastejo de 15 como na de 30 cm, evidenciando que essa espécies é promissora para uso em sistemas intensivos de pastejo.
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Netto, Diego Peres [UNESP]. "Desempenho e comportamento de vacas leiteiras em pastagem de alfafa suplementada com silagem de milho e concentrado." Universidade Estadual Paulista (UNESP), 2009. http://hdl.handle.net/11449/104118.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Universidade Estadual Paulista (UNESP)
Objetivou-se avaliar como a substituição parcial de silagem de milho por pastagem de alfafa afeta o desempenho de vacas leiteiras e a viabilidade econômica do sistema. Usaramse 24 vacas da raça Holandesa, em estádio médio de lactação, num delineamento em blocos ao acaso. O período experimental durou 84 dias. Os tratamentos foram: dieta à base de silagem de milho em confinamento; ou silagem de milho substituída parcialmente por pastejo restrito (limitado a quatro horas/dia) ou irrestrito de alfafa. O pastejo foi rotacionado, e a quantidade de concentrado igual (4,5 kg de MS/vaca/dia) em todos os tratamentos. A massa de forragem foi 2338,0 e 1878,0 kg de MS/ha e a oferta, 1,8 e 4,2 kg MS/100 kg PV, nos tratamentos pastejo restrito e irrestrito, respectivamente. A produção de leite não diferiu entre tratamentos, cujas médias foram 25,9±1; 25,8±1 e 25,2±1 litros/vaca/dia no confinamento, pastejo restrito e pastejo irrestrito, respectivamente. A produção de leite por área foi 59 litros/ha/dia no pastejo restrito e 63 litros/ha/dia no pastejo irrestrito, enquanto no confinamento foi 48 litros/ha/dia. A substituição parcial de silagem de milho por alfafa em pastejo não limitou o desempenho produtivo dos animais e mostrou-se economicamente vantajosa em relação ao confinamento.
The objective was to evaluate how the partial replacement of corn silage with alfafa grazing affects dairy cow performance and profitability. Twenty four Holstein dairy cows in mid-lactation were used in a randomized block design. The experimental period lasted 84 days. The treatments were: a corn silage-based diet fed on drylot; or partial replacement of corn silage with either restricted alfalfa grazing (limited to 4 hours/day) or unrestricted grazing. A rotational grazing system was used and the amount of concentrate fed was the same (4.5 kg of DM/cow/day) for all treatments. Forage availability was 2,338.0 and 1,878.0 kg DM/ha and forage-on-offer was 1.8 and 4.2 kg DM/100 kg LW under restricted or unrestricted grazing, respectively. No difference in milk production/cow/day was observed among treatments. Mean milk production was 25.9±1, 25.8±1 and 25.2±1 liters/cow/day for feedlot, restricted grazing or unrestricted grazing, respectively. Milk production per hectare was 59 liters/day under restricted grazing and 63 liters/day under unrestricted grazing, whereas it was 48 liters/day on drylot. The partial replacement of corn silage by alfalfa grazing did not limit animal performance and was shown to be economically advantageous as compared to drylot feeding.
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Ballesteros, Raúl David Guevara. "Enteric Methane and Nitrogen Emissions in Beef Cattle Grazing a Tannin-Containing Legume Relative to Feedlot and Traditional Pasture-Based Production Systems." DigitalCommons@USU, 2019. https://digitalcommons.usu.edu/etd/7666.

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Beef cattle production is highly criticized because of the high use of land and water resources, and by the pollution (e.g., the gas methane in a cow’s breath and nitrogen in urine) produced by cows fed in feedlots. In contrast to feedlots diets and grasses, some plants (e.g., legumes) contain bioactive compounds (condensed tannins) that reduce pollution and enhance animal nutrition. In my research, I observed that cows grazing a tannin-containing legume (birdsfoot trefoil; BFT) had methane emissions similar to cows fed a feedlot ration with comparable weight gains. Cows in the BFT treatment gained more weight than cows grazing grass (meadow brome) or a legume without tannins (cicer milkvetch). Additionally, I estimated the potential areas in the state of Utah than can sustain birdsfoot trefoil production, with 412,250 ha distributed mostly in the Box elder, Cache, Millard and Sanpete counties. Thus, feeding tannin-containing legumes to cows is a viable alternative to feedlot rations, with greater levels of productivity than other pasture-based systems, which can lead to a more sustainable production of beef.
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Schaak, Henning [Verfasser], Oliver [Akademischer Betreuer] Mußhoff, Oliver [Gutachter] Mußhoff, Achim [Gutachter] Spiller, and Ulf [Gutachter] Liebe. "Agricultural and societal perspectives on pasture-based livestock production systems in Germany / Henning Schaak ; Gutachter: Oliver Mußhoff, Achim Spiller, Ulf Liebe ; Betreuer: Oliver Mußhoff." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://d-nb.info/1201548950/34.

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Schaak, Henning [Verfasser], Oliver [Akademischer Betreuer] Mußhoff, Oliver Gutachter] Mußhoff, Achim [Gutachter] [Spiller, and Ulf [Gutachter] Liebe. "Agricultural and societal perspectives on pasture-based livestock production systems in Germany / Henning Schaak ; Gutachter: Oliver Mußhoff, Achim Spiller, Ulf Liebe ; Betreuer: Oliver Mußhoff." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2019. http://nbn-resolving.de/urn:nbn:de:gbv:7-21.11130/00-1735-0000-0005-12C5-8-7.

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Marandure, Tawanda. "Sustainability of smallholder cattle production and its vertical integration into the formal beef market value chain in South Africa." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/97974.

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Thesis (MSc)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: A survey to assess the sustainability and marketing opportunities for smallholder cattle production systems was conducted by consulting with a total of 95 smallholder cattle producers in Ncorha and Gxwalibomvu communities in the Eastern Cape Province (ECP) of South Africa. In addition, a total of 18 surrounding beef retailers, 5 abattoirs that supplied beef to these retailers and 155 beef consumers who bought beef from these retailers between February 2013 and February 2014 were also interviewed using pretested structured questionnaires. The surveys established the perception of beef traders and consumers on the development of a Natural beef (NB) brand and indicated the willingness of participants to support the development of a NB brand. The results indicated that a smallholder beef cattle production system was socially and environmentally conditionally sustainable but economically not sustainable. Overall, the system was conditionally sustainable. Cattle herd size was bigger in Ncorha than in Gxwalibomvu (13.7±1.9 vs. 11.3 ± 1.9 heads of cattle, respectively). Smallholder producers from both sites sold an average of two cattle per year. Young farmers (<40 years old), Christians and small households (<5 members) had a greater potential to sell cattle than adults (>40 years old), traditionalists and larger households (>5 members). Similarly, households with access to extension services, owners of smaller cattle herds (<10 cattle) and from a lower income bracket (AFRIKAANSE OPSOMMING:'n Opname om die volhoubaarheid en bemarkingsgeleenthede vir kleinboer vleisbeesproduksiestelsels te evalueer, is deur middel van konsultasie met 'n totaal van 95 kleinboere vee produsente in Ncorha en Gxwalibomvu gemeenskappe in die Oos-Kaap Provinsie van Suid-Afrika, uitgevoer. Daarbenewens is altesame 18 omliggende vleis kleinhandelaars, 5 abattoirs wat beesvleis verskaf aan hierdie kleinhandelaars en 155 beesvleis verbruikers wat vleis gekoop het van die kleinhandelaars tussen Februarie 2013 en Februarie 2014, met behulp van vooraf-getoetste gestruktureerde vraelyste ondervra. Die opnames het die mening van beesvleis handelaars en -verbruikers oor die ontwikkeling van 'n natuurlike weiding-geproduseerde beesvleis (NPB) handelsmerk ingewin en ook die bereidwilligheid van die deelnemers om die ontwikkeling van 'n NPB handelsmerk te ondersteun, aangedui. Die bevindinge dui daarop dat 'n kleinskaalse vleisbees produksiestelsel sosiaal en omgewingsvriendelik voorwaardelik volhoubaar is, maar nie ekonomies volhoubaar is nie. In geheel is hierdie tipe produksiestelsel as voorwaardelik volhoubaar beskou. Beestrop grootte was groter in die Ncorha as in die Gxwalibomvu gemeenskappe (13.7 ± 1.9 beeste vs. 11.3 ± 1.9 beeste, onderskeidelik). Kleinboer produsente van beide areas het 'n gemiddeld van twee beeste per jaar verkoop. Jong boere (<40 jaar oud), Christene en klein huishoudings (<5 lede) het 'n beter potensiaal gehad om beeste te verkoop as volwassenes (> 40 jaar oud), tradisionele boere en groter huishoudings (> 5 lede). Net so het huishoudings met toegang tot voorligtingsdienste, eienaars van klein troppe (<10 beeste) en boere wat aan die laer inkomstegroep behoort het (
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39

Provazi, Milena 1981. "Avaliação de espécies de Paspalum sob pastejo /." Botucatu : [s.n.], 2006. http://hdl.handle.net/11449/95218.

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Resumo: O objetivo deste experimento foi verificar o efeito do pastejo sobre a produtividade e a persistência de três acessos de Paspalum. O experimento foi desenvolvido na Embrapa Pecuária Sudeste, localizada em São Carlos-SP, no período de janeiro a dezembro de 2005. Foram comparados três acessos de Paspalum (Paspalum guenoarum - BRA-006572, Paspalum malacophyllum - BRA-003077 e Paspalum sp. - BRA-011681) e duas testemunhas (Brachiaria decumbens e Paspalum atratum cv. Pojuca) quando submetidos a dois níveis de desfolha (1.500 e 3.000 kg MS/ha de resíduo pós-pastejo). O ensaio foi do tipo "mob grazing", utilizando o método de pastejo rotacionado com 27 dias de descanso e 1 dia de ocupação (período das águas) e 55 dias de descanso e 1 dia de ocupação (período das secas). A taxa de lotação animal das parcelas foi ajustada de acordo com a massa de forragem disponível antes do pastejo e com o nível de desfolha previsto pelo tratamento. As variáveis foram: massa de forragem antes e após o pastejo; proporções de folhas, hastes e material morto; densidade de perfilhos; incidência de plantas invasoras; observações relativas à susceptibilidade a pragas e doenças, sintomas de toxidez e deficiência mineral. O Paspalum atratum mostrou características positivas de produção e persistência tanto na altura de pastejo de 15 como na de 30 cm, evidenciando que essa espécies é promissora para uso em sistemas intensivos de pastejo.
Orientador: Ciniro Costa
Coorientador: Patrícia Menezes Santos
Banca: Mário De Beni Arrigoni
Banca: Luiz Alberto Rocha Batista
Abstract: The objective of this experiment was to verify the outcome of the grazing above the productivity and the persistence of three accesses of Paspalum. The experiment was developed on Southeastern Cattle Embrapa, in São Carlos, SP, in the period of January to December 2005. Three genotypes of Paspalum (Paspalum. guenoarum - BRA-006572, Paspalum malacophyllum - BRA-003077 e Paspalum sp - BRA-011681) and two controls (Brachiaria decumbens and Paspalum atratum cv. Pojuca) were compared under two grazing intensities (1.500 and 3.000 kg MS/ha of post-graze residue). Plots were mob grazed (1-day grazing followed by 27-day rest (water period) and 1-day grazing followed by 55-day rest (dry period) and stocking rate was adjusted according to the herbage mass available and the treatment grazing intensity. The following variables have been evaluated: total herbage mass before and after grazing; proportion of leaf, stem and dead material; occurrence of weeds and tiller density and occurrence of diseases and symptoms of mineral toxicity or deficiency. For both grazing intensities the Paspalum atratum demonstrated positive characteristics of production and persistence indicating that these are promising genotypes for use in intensive systems of pasture.
Mestre
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40

Campbell, Braden Joseph. "Alternative management practices to improve the growth and mitigate the health and economic losses associated with parasitic infection in pasture-raised lambs in the eastern United States of America." The Ohio State University, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=osu1619020179009712.

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41

Werner, Jessica [Verfasser], and Matthias [Akademischer Betreuer] Schick. "Measuring grazing behaviour of dairy cows : validation of sensor technologies and assessing application potential in intensive pasture-based milk production systems / Jessica Werner ; Betreuer: Matthias Schick." Hohenheim : Kommunikations-, Informations- und Medienzentrum der Universität Hohenheim, 2019. http://d-nb.info/1182423558/34.

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42

Joubert, Matthys Du Toit. "The effect of concentrate feeding strategies on rumen parameters, milk production and milk composition of Jersey cows grazing ryegrass (Lolium multiflorum) or kikuyu (Pennisetum clandestinum) pasture." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20069.

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Thesis (MScAgric)--Stellenbosch University, 2012
ENGLISH ABSTRACT: Ruminal pH is the rumen condition that varies most. Studying the cause and effect of diurnal variation offers a means of improving ruminal conditions for rumen micro-organisms with subsequent improvements in fibre degradation, milk yields and milk composition. A research project was conducted to test the following hypothesis: feeding 6 kg (as is) concentrate per cow/day in different weight ratios, divided in a morning and an afternoon allocation, will result in an improved ruminal pH profile and a concurrent increase in fibre fermentation, milk yield and improved milk composition. The project was conducted at the Outeniqua Research Farm in the Southern Cape of South Africa. A randomized block design was used and two phases, viz. ryegrass phase and a kikuyu phase, were applied. Each phase was conducted during the growing season of the grass specie used as pasture. A rumen study and a production study were done in each phase. The rumen study used six cannulated multiparous cows per treatment, testing rumen pH, volatile fatty acid (VFA) concentration, in sacco degradation of neutral detergent fibre (NDF) and dry matter (DM). The production study used 42 multiparous cows, blocked according to days in milk (DIM), parity and milk yield, and cows were randomly divided into three treatment groups. The study tested milk yield, milk composition and changes in body weight (BW) and body condition score (BCS). Treatments consisted of a maize based concentrate supplement (6 kg per cow/day, as is) being fed to cows on pasture in different weight ratios between morning and afternoon allocation. Treatments used in the production study were: Concentrate fed: 5 kg during morning; 1 kg during afternoon • Concentrate fed: 4 kg during morning; 2 kg during afternoon • Concentrate fed: 3 kg during morning; 3 kg during afternoon The first and the last treatments mentioned above were used in the rumen studies. Results of the rumen study of the ryegrass phase showed no differences in ruminal pH between treatment means. The time (h) spent below the critical ruminal pH, i.e. 5.8, was of short duration (2.92 to 3.42 hours). The concentration of certain VFA’s differed at times, but the differences were not reflected in graphs and data of the ruminal pH. No differences were observed in in sacco NDF and DM degradation between treatment means. Similar results were mostly obtained in the kikuyu phase. No differences were found in either daily maximum, minimum or mean ruminal pH between treatment means. Though time (h) spent below the critical ruminal pH was of a long duration (7.1 hours) it did not differ between treatments. No differences were observed between treatment means for in sacco NDF and DM degradation. Results of the production study of the ryegrass phase showed no differences in milk yield or milk composition between treatment means. The same was observed in the kikuyu phase except that milk fat was higher in the treatment group that received the 3:3 kg ratio treatment. The fact that treatments did not differ in terms of milk yield and milk composition in the production studies can be attributed to no differences between treatments in terms of rumen parameters observed in the rumen studies. Thus, feeding a higher proportion of concentrate in the morning relative to the afternoon for a total of 6 kg per cow/day does not affect ruminal pH, fibre digestion or milk production. Based on the results of both phases it can be concluded that the null hypothesis should be rejected.
AFRIKAANSE OPSOMMING: Die invloed van kragvoer voedingsstrategieë op rumen parameters, melkproduksie en melksamestelling van Jerseykoeie op raaigras- (Lolium multiflorum) of kikoejoe- (Pennisetum clandestinum) weidings. Die invloed van kragvoer voedingsstrategieë op rumen parameters, melkproduksie en melksamestelling van Jerseykoeie op raaigras- (Lolium multiflorum) of kikoejoe- (Pennisetum clandestinum) weidings. Behandelings toegepas in die produksiestudie het bestaan uit ‘n kragvoeraanvulling met ‘n mieliebasis wat aan koeie op weidings gevoer is in verskillende gewigsverhoudings tussen oggend- en middagvoeding, as volg: Behandelings toegepas in die produksiestudie het bestaan uit ‘n kragvoeraanvulling met ‘n mieliebasis wat aan koeie op weidings gevoer is in verskillende gewigsverhoudings tussen oggend- en middagvoeding, as volg:
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43

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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44

Costa, Francivaldo Oliveira. "Características agronômicas, valor nutritivo e comportamento de pastejo de ovinos em capim-Tanzânia em função de alturas de resíduo e idades de rebrotação." Universidade Federal do Maranhão, 2016. http://tedebc.ufma.br:8080/jspui/handle/tede/568.

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Made available in DSpace on 2016-08-17T17:11:05Z (GMT). No. of bitstreams: 1 Dissertacao-FrancivaldoOliveiraCosta.pdf: 618089 bytes, checksum: 295ca37302d02cb8869c31e4539d6b80 (MD5) Previous issue date: 2016-02-29
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The objective of this study morphogenic characteristics, demographic, productive, nutritious and behavior of grazing sheep in Tanzania grass pasture managed at different heights residue and regrowth ages. The experiment was conducted at the Forage sector of the Center for Agricultural and Environmental Sciences, Federal University of Maranhão, in the municipality of Chapadinha - MA. The experimental design was completely randomized in a factorial arrangement 2x3, two cutting heights (30 and 50 cm) and three regrowth ages (18, 30 and 42 days), a total of six treatments. For production, morfogêneses, demographic and nutritional value used were four replicates (each replicate was characterized by a picket) in relation to grazing behavior were used five replicates (each replicate was characterized by an animal). In morphogenic variables, the residual height had no effect (P>0.05). At the age of 18 days of regrowth, the highest leaf appearance rates were observed (LAR), phyllochron (FIL) and leaf elongation (LER). Regarding the demographic patterns of tillers, there was no effect (P>0.05) the height of waste and interaction between the factors. At the age of 42 days, greater rates of appearance and mortality of tillers were presented, and higher survival rate was observed after 18 days. The highest total dry matter yield (PMST), dried pasta sheet (PMSF) and dry mass stem (PMSC) were observed (P<0.05) in treatment with 30 cm residue and regrowth 42 days. For the chemical composition, the variables of the leaf blade: PB (CP), NDF (neutral detergent fiber), FDA (acid detergent fiber), MS (dry matter) and MM (mineral matter), showed effect (P<0.05) interaction, whereas the stem was no interaction effect only for the CP and MM (P<0.05). The grass handled at 18 days showed higher levels of CP compared to 42 days in both heights and a fraction of the plant. NDF, ADF and LIG were higher after 42 days, and little influenced by waste time, especially in stem fraction. The degradability of dry matter (DMD), at 18 days, the greatest potential and effective degradability values were presented. For grazing behavior, only the variable: time for other activities (OAS), showed no interaction effect (P>0.05). The Tanzania grass managed to 42 days results in high grazing time in both waste heights. The most idle time is observed at the age of 30 days. We conclude that the management of Tanzania grass pasture with different heights residue and regrowth ages influence the production, nutritive value and grazing behavior. Morphogenetic and demographic characteristics are not influenced by waste heights. It is recommended to manage the Tanzania grass maintaining 30 cm residue with 30 days regrowth.
Objetivou-se com o presente trabalho avaliar as características morfogênicas, demográficas, produtivas, valor nutritivo e o comportamento de pastejo de ovinos em pastagem de capim-Tanzânia manejado em diferentes alturas de resíduo e idades de rebrotação. O experimento foi conduzido no setor de Forragicultura do Centro de Ciências Agrárias e Ambientais da Universidade Federal do Maranhão, no município de Chapadinha MA. O delineamento experimental foi o inteiramente casualizado em arranjo fatorial 2x3, duas alturas de corte (30 e 50 cm) e três idades de rebrotação (18, 30 e 42 dias), totalizando seis tratamentos. Para a produção, morfogêneses, demografia e valor nutritivo foram utilizados quatro repetições (cada repetição foi caracterizada por um piquete), em relação ao comportamento de pastejo foram utilizados cinco repetições (cada repetição foi caracterizada por um animal). Nas variáveis morfogênicas, a altura de resíduo não teve efeito (P>0,05). Na idade de 18 dias de rebrotação, foram observadas as maiores taxas de aparecimento foliar (TApF), filocrono (FIL) e alongamento foliar (TAlF). Em relação aos padrões demográficos de perfilhos, não houve efeito (P>0,05) da altura de resíduo e de interação entre os fatores. Na idade de 42 dias, foram apresentadas as maiores taxas de aparecimento e mortalidade de perfilhos, e a maior taxa de sobrevivência foi observada aos 18 dias. As maiores produções de massa seca total (PMST), massa seca de folha (PMSF) e massa seca de colmo (PMSC), foram observadas (P<0,05) no tratamento com 30 cm de resíduo e 42 dias de rebrotação. Para a composição química, as variáveis da lâmina foliar: PB (proteína bruta), FDN (fibra em detergente neutro), FDA (fibra em detergente ácido), MS (matéria seca) e MM (matéria mineral), apresentaram efeito (P<0,05) de interação, enquanto que no colmo houve efeito de interação somente para a PB e MM (P<0,05). O capim manejado aos 18 dias apresentou maiores teores de PB em comparação aos 42 dias, em ambas as alturas e fração da planta. Os teores de FDN, FDA e LIG foram maiores aos 42 dias, sendo pouco influenciada pela altura de resíduo, principalmente na fração colmo. Na degradabilidade da matéria seca (DMS), aos 18 dias, foram apresentados os maiores valores de degradabilidade potencial e efetiva. Para o comportamento de pastejo, somente a variável: tempo para outras atividades (OAS), não apresentou efeito de interação (P>0,05). O capim-Tanzânia manejado aos 42 dias resulta em elevado tempo de pastejo em ambas as alturas de resíduo. O maior tempo de ócio foi observado na idade de 30 dias. Conclui-se que o manejo da pastagem de capim-Tanzânia com diferentes alturas de resíduo e idades de rebrotação influenciam na produção, valor nutritivo e comportamento de pastejo. As características morfogênicas e demográficas não são influenciadas pelas alturas de resíduos. Recomenda-se manejar o capim-Tanzânia mantendo 30 cm de resíduo com 30 dias de rebrotação.
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45

Orbolato, Cintia Cristina. "Efeito do financiamento rural sobre a viabilidade econômico-financeira em projetos de bovinos de corte em sistema de cria." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/74/74134/tde-13032019-103651/.

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O propósito do Sistema Nacional do Crédito Rural (SNCR) elaborado pelo Governo Federal nos anos de 1960 foi ofertar, por meio de programas de financiamento, taxas de juros e prazos para pagamentos subsidiados, a fim de modernizar e fortalecer a agricultura e a pecuária brasileira. Entretanto, para acessar esses empréstimos exigem garantias e nem sempre os recursos disponibilizados promovem as melhorias esperadas no setor agropecuário. Os objetivos deste estudo foram: analisar as linhas de financiamento de custeio e de investimento disponibilizadas para a atividade de bovinocultura de corte; e comparar a viabilidade econômico-financeira de projetos de sistema de criação de bovinos, por meio da utilização de crédito rural e de capital próprio. Foi realizada revisão do SNCR para se entender o funcionamento e aplicabilidade do financiamento na agropecuária. Modelo matemático para cálculo dos custos de produção e de demonstrativo de fluxo de caixa foi utilizado para estimar indicadores econômicos e financeiros. Os conceitos da Teoria Econômica foram considerados para calcular o Custo Operacional Efetivo, Custo Operacional Total e o Custo Total. O Valor Presente Líquido (VPL), Taxa Interna de Retorno (TIR), Payback Simples e Descontado foram os indicadores financeiros utilizados. Uma fazenda representativa da produção de bovinos de corte em sistema de cria foi proposta para a região de Presidente Prudente no Estado de São Paulo. Simulações foram realizadas para cenários em dois níveis tecnológicos, e sem ou com a utilização de crédito rural. Os resultados econômicos mais favoráveis foram encontrados ao adotar nível maior de tecnologia, isso ocorreu devido ao aumento da produtividade por área que diluiu os custos fixos pela quantidade de produto produzido - bezerros(as). O Custo Operacional Total do bezerro no cenário com nível inferior de tecnologia foi de R$ 4,84/kg, enquanto que para o cenário com nível mais elevado foi de R$ 4,10/kg. Em relação aos resultados financeiros, todos os cenários propostos foram favoráveis, com o VPL positivo, a TIR média de 9% ao ano e o retorno do projeto ocorreu dentro do prazo estabelecido para o projeto (30 anos). Os maiores VPL e TIR ocorreram para o cenário no qual utilizava-se maior tecnologia e capital financiado (cenário 4). O menor Payback Simples (11 anos) e Payback Descontado (17 anos) ocorreram com utilização de capital próprio e baixa tecnologia (cenário 1). Concluiu-se que, adotar maior nível de tecnologia melhorou os resultados econômicos, e a utilização de maior tecnologia juntamente com o crédito rural resultou na melhor viabilidade econômico-financeira para o produtor. Por fim, os resultados de sistemas com tecnologia mais avançada demonstraram que, o uso do crédito rural pode ser uma estratégia para alavancar a produção de bezerros de corte.
The goal of the National Rural Credit System (SNCR) prepared by the Federal Government in the 1960s was to offer, through financing programs, interest rates and terms for subsidized payments, in order to improve and consolidate of Brazilian agriculture and livestock. However, to access these loans guarantees are required, and the available resources do not always foment the expected improvements in the agricultural and livestock sector. The aims of this study were: to analyse the defrayal and investment credit lines made available for the beef cattle; and to compare the economic-financial feasibility of beef calves projects, through the use of rural credit and own resources. A review of SNCR has been carried out to understand the operation and application of livestock financing. Mathematical model for calculation of production costs and cash flow statement was used to estimate economic and financial indicators. The concepts of Economic Theory were considered to calculate the Effective Operational Cost, Total Operational Cost and Total Cost. The Net Present Value (NPV), Internal Rate of Return (IRR), Simple and Discounted Payback were the financial indicators used. The representative farm of beef calves production was proposed for the region of Presidente Prudente in São Paulo State. Simulations were performed for scenarios at two technological levels, and without or with the rural credit use. The most favourable economic results were found when adopting a higher level of technology, this ocurred due to the increase in productivity per area which diluted the fixed costs by the quantity of product produced - calves. The Total Operational Cost of the calf in the scenario with lower level of technology was R$ 4.84/kg, while for the scenario with the highest level it was R$ 4.10/kg. Regarding the financial results, all the scenarios proposed were favourable, with the NPV positive, the average IRR of 9% per year and the project return occurred within the deadline established for the project (30 years). The highest NPV and IRR occurred for the scenario in which more technology and credit rural were used (scenario 4). The lowest Simple Payback (11 years) and Discounted Payback (17 years) occurred with the use of own resources and low technology (scenario 1). It was concluded that, the adoption of more technology improved the economic results and the utilization of more technology with rural credit resulted in the best economic-financial feasibility for the farmer. Finally, the results of systems with more technology demonstrated that the use of the rural credit can be a strategy to leverage the production of beef calves.
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46

Tonmukayakul, Nop. "Water use efficiency of six dryland pastures in Canterbury." Lincoln University, 2009. http://hdl.handle.net/10182/1498.

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The annual and seasonal water use efficiency of six pasture combinations were calculated from the ‘MaxClover’ Grazing Experiment at Lincoln University. Pastures have been established for six years and are grazed by best management practices for each combination. Measurements for this study are from individual plots of four replicates of ryegrass (RG)/white clover (Wc), cocksfoot (CF)/Wc; CF/balansa (Bal) clover; CF/Caucasian (Cc) clover; CF/subterranean (Sub) clover or lucerne. Water extraction measurements showed soils for all dryland pastures had a similar plant available water content of 280±19.8 mm. Dry matter measurements of yield, botanical composition and herbage quality were assessed from 1 July 2008 until 30 June 2009. Lucerne had the highest annual yield of 14260 kg DM/ha/y followed by the CF/Sub at 9390 kg DM/ha/y and the other grass based pastures at ≤ 6900 kg DM/ha/y. All pastures used about 670±24.4 mm/y of water for growth. Lucerne had the highest annual water use efficiency (WUE) of 21 kg DM/ha/mm/y of water used (total yield/total WU). The WUE of CF/Sub was the second highest at 15 kg DM/ha/mm/y, and the lowest was CF/Wc at 9 kg DM/ha/mm/y. The CF/Sub pastures had the highest total legume content of all grass based pastures at 21% and as a consequence had the highest annual nitrogen yield of 190 kg N/ha. This was lower than the monoculture of lucerne (470 kg N/ha). Ryegrass/white clover had the highest total weed component in all pastures of 61%. For dryland farmers spring is vital for animal production when soil temperatures are rising and moisture levels are high. The water use efficiency at this time is important to maximize pasture production. In spring lucerne produced 8730 kg DM/ha, which was the highest dry matter yield of all pastures. The CF/Sub produced the second highest yield of 6100 kg/DM/ha. When calculated against thermal time, CF/Sub grew 5.9 kg DM/ºCd compared with lucerne at 4.9 kg DM/ºCd. The higher DM yield from lucerne was from an extra 400 ºCd of growth. The highest seasonal WUE of all pastures occurred in the spring growing period. Linear regressions forced through the origin, showed lucerne (1/7/08-4/12/08) had a WUE of 30 kg DM/ha/mm (R2=0.98). Of the grass based pastures, CF/Sub produced 18 kg DM/ha/mm (R2=0.98) from 1/7 to 10/11/08 from 270 mm of water used. The lowest spring WUE was 13.5 kg DM/ha/mm by CF/Bal pastures which was comparable to the 14.3±1.42 kg DM/ha/mm WUE of CF/Wc, CF/Cc and RG/Wc pastures. During the spring, CF/Sub clover had the highest spring legume component of the grass based pastures at 42% and produced 120 kg N/ha. This was lower than the 288 kg N/ha from the monoculture of lucerne. Sub clover was the most successful clover which persisted with the cocksfoot. Based on the results from this study dryland farmers should be encouraged to maximize the potential of lucerne on farm, use cocksfoot as the main grass species for persistence, rather than perennial ryegrass, and use subterranean clover as the main legume species in cocksfoot based pastures. By increasing the proportion of legume grown the water use efficiency of a pasture can be improved. When pastures are nitrogen deficient the use of inorganic nitrogen may also improve pasture yields particularly in spring.
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47

Agastin, Aurélie. "Evaluation et comparaison de deux modes de production contrastés pratiqués en zone tropicale : la conduite à l’auge vs la conduite au pâturage." Thesis, Antilles-Guyane, 2013. http://www.theses.fr/2013AGUY0675/document.

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Le pâturage, principal mode d’alimentation en zone tropicale, est souvent dévalorisé car il est associé à des performances animales jugées insuffisantes, et peut avoir des effets néfastes sur l’environnement. Même si l’alimentation à l’auge permet de meilleures productions, ce mode de conduite présente également des inconvénients, en termes d’investissements, de rentabilité économique, d’impact des rejets sur l’environnement et de qualité des produits. Une intensification de la conduite au pâturage semble donc une voie d’avenir, mais nécessite une meilleure connaissance de ce mode de conduite et de ses conséquences sur l’alimentation et les performances des animaux. Il apparait également nécessaire de comparer l’élevage au pâturage et à l’auge sur des critères homogènes, en dissociant les composantes de ces modes de conduite.L’objectif de la thèse est d’évaluer et de comparer la conduite au pâturage et la conduite hors sol, en tenant compte également de la distribution ou non de concentré, sur l’alimentation, la croissance, les caractéristiques d’abattage et la consommation d’eau. Dans un premier temps, nous avons étudié au cours d’une expérimentation, les effets de ces deux modes de conduite sur la croissance, les caractéristiques d’abattage et de carcasse de taurillons Créoles abattus à deux âges (précoce vs tardif). Les taurillons à l’auge avaient une croissance plus rapide, des poids de carcasse plus élevés, ainsi que des carcasses plus grasses. Nous avons observé qu’abattre plus tardivement au pâturage (17 et 21 mois vs 14 et 17 mois à l’auge), permettait d’atteindre des poids finaux similaires à ceux obtenus à l’auge et des carcasses de meilleure qualité, plus riche en muscle. Nous avons expliqué la majorité de nos résultats par les effets combinés des modes de conduite et de l’alimentation et avons voulu étudier leurs effets respectifs. Dans un second temps, l’étude des effets du mode de conduite a été faite dans un premier temps, par le biais d’une méta-analyse. Les performances des animaux à l’auge étaient meilleures qu’au pâturage, mais ces effets dépendaient de la stratégie de complémentation. De cette méta-analyse est également apparu le manque d’études auge vs pâturage sur l’alimentation et à ration égale. Afin d’étudier les effets respectifs du mode de conduite et de la stratégie de complémentation, un dispositif analytique avec des taurillons élevés à l’auge et au pâturage complémentés ou non avec du concentré a été mis en place. Dans un premier temps, une étude méthodologique menée grâce à ce dispositif nous a permis d’identifier que la SPIR permettait la meilleure estimation de la dMO, l’OMI et la MODI au pâturage. Les résultats de l’étude analytique ont montré que les animaux au pâturage utilisaient mieux leur alimentation pour leur croît que ceux à l’auge et la stratégie de complémentation influençait davantage ces variables que le mode de conduite. Avec une stratégie de complémentation appropriée, les animaux au pâturage peuvent atteindre des performances similaires à celles obtenues à l’auge
Grazing, main way of feeding ruminants in the tropics, is often undervalued because it is associated with animal performance deemed insufficient, and may have adverse effects on the environment. Even if stall feeding allows better production, this way of feeding has drawbacks in terms of investment, profitability, impact of emissions on the environment and product quality. Intensification of grazing seems a way forward, but requires a better understanding of this way of feeding and its impact on feeding and animal performance. It also appears necessary to compare grazing and stalls feeding on homogeneous criteria, separating the components of these modes of management.The aim of the thesis is to evaluate and compare stalls and pasture feeding environment, taking into account also the distribution or not of concentrate on feeding, growth, slaughter characteristics and water consumption. At first , we studied in an experiment , the effects of these two feeding systems on growth, slaughter and carcass characteristics of Creoles bulls slaughtered at two ages (early vs. late ). Bulls fed in trough grew faster, had greater carcass weight and fatter carcasses. We observed that a later slaughter of grazing animals (17 and 21 months vs. 14 and 17 months in stalls), allowed to reach final weights similar to those obtained in stalls and carcasses richer in muscle. We explained most of our results by the combined effects of feeding environment and complementation strategy and wanted to study their effects. In a second step, the study of the effects of feeding environment was made in first instance, through a meta-analysis. Stalls fed animals had greater performances than pasture fed ones, but these effects depended on complementation strategy. This meta-analysis also highlighted the lack of knowledge on intake and digestibility at pasture, which is a limitation on attempts to compare with measurements carried out in trough-fed animals. To investigate the relative effects of feeding environment and complementation strategy, we conceived an analytical trial with Creole bulls reared in stalls and at pasture, supplemented or not with concentrate. First of all, this analytical trial was the support of a methodological study, which identified that the NIRS method allows the best estimate of the OMD, OMI and DOMI at pasture. The analytical trial showed that grazing animals had better feed efficiency feed for their growth than stall fed ones and complementation strategy influenced more these variables than feeding environment. With an appropriate strategy for complementation, grazing animals can achieve similar performance to those obtained at the trough
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48

Schären, Melanie [Verfasser]. "“Effects of a ration change from a silage and concentrate- to a pasture-based ration on the production, health and rumen physiology of dairy cows” / Melanie Schären." Hannover : Bibliothek der Tierärztlichen Hochschule Hannover, 2016. http://d-nb.info/1107031451/34.

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49

Echols, Allison Clare. "Relationships among lifetime measures of growth and frame size for commercial beef females in a pasture-based production system in the Appalachian region of the United States." Thesis, Virginia Tech, 2011. http://hdl.handle.net/10919/35076.

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The beef cattle industry has placed increased focus on mature cow size as a result of its influence on production efficiency and profitability. The objectives of this study were to evaluate relationships among lifetime measures of body weight (BW) and frame score (FS) in commercial beef females, and to assess the value of immature measures as predictors of mature cow size. Measurements of BW, hip height (HH), body condition score (BCS), and calculated FS were recorded at weaning (WN), breeding at 13 mo age (BR), and 8 subsequent periods, ceasing at approximately 5 yr of age for 232 Angus-cross females born 2004 through 2008. Correlation analysis revealed significant (P < 0.001) relationships among BW taken at WN and BR with BW measurements taken at 2.5, 3.8, and 4.8 yr of age (WN r = 0.70, 0.51, 0.61; BR r = 0.65, 0.57, 0.64, respectively). Significant relationships (P < 0.001) existed between FS collected at WN and BR, and FS at 2.5 and 3.8 yr (WN= 0.70, 0.72; BR= 0.79, 0.82, respectively). Repeatability of lifetime FS measures was 0.73. BCS was a significant (P < 0.001) source of variation in mature BW, with a unit change in BCS accounting for 41 kg BW change at 4.8 yr (P < 0.001). BW and FS were moderately to strongly related (P < 0.001) at WN, BR, 2.5, 3.8, and 4.8 yr (r = 0.62, 0.49, 0.62, 0.62, and 0.47 respectively). Prediction models for BW at 4.8 yr were similar using weaning BW alone, or with inclusion of both weaning BW and HH (R2 = 0.57 and 0.56). Similarly, breeding BW and HH were non-additive for prediction of 4.8 yr BW (R2 = 0.68, 0.58, and 0.68 for BW, HH, and BW +HH respectively). Performance at immature ages proves to be a satisfactory indicator of mature size, supporting continued incorporation of immature BW and HH and/or FS measurements into selection practices.
Master of Science
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Netto, Diego Peres 1978. "Desempenho e comportamento de vacas leiteiras em pastagem de alfafa suplementada com silagem de milho e concentrado /." Botucatu : [s.n.], 2009. http://hdl.handle.net/11449/104118.

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Orientador: Francisco Stefano Wechsler
Banca: Ciniro Costa
Banca: Paulo Roberto de Lima Meirelles
Banca: Armando de Andrade Rodrigues
Banca: Mauro Del Secco
Resumo: Objetivou-se avaliar como a substituição parcial de silagem de milho por pastagem de alfafa afeta o desempenho de vacas leiteiras e a viabilidade econômica do sistema. Usaramse 24 vacas da raça Holandesa, em estádio médio de lactação, num delineamento em blocos ao acaso. O período experimental durou 84 dias. Os tratamentos foram: dieta à base de silagem de milho em confinamento; ou silagem de milho substituída parcialmente por pastejo restrito (limitado a quatro horas/dia) ou irrestrito de alfafa. O pastejo foi rotacionado, e a quantidade de concentrado igual (4,5 kg de MS/vaca/dia) em todos os tratamentos. A massa de forragem foi 2338,0 e 1878,0 kg de MS/ha e a oferta, 1,8 e 4,2 kg MS/100 kg PV, nos tratamentos pastejo restrito e irrestrito, respectivamente. A produção de leite não diferiu entre tratamentos, cujas médias foram 25,9±1; 25,8±1 e 25,2±1 litros/vaca/dia no confinamento, pastejo restrito e pastejo irrestrito, respectivamente. A produção de leite por área foi 59 litros/ha/dia no pastejo restrito e 63 litros/ha/dia no pastejo irrestrito, enquanto no confinamento foi 48 litros/ha/dia. A substituição parcial de silagem de milho por alfafa em pastejo não limitou o desempenho produtivo dos animais e mostrou-se economicamente vantajosa em relação ao confinamento.
Abstract: The objective was to evaluate how the partial replacement of corn silage with alfafa grazing affects dairy cow performance and profitability. Twenty four Holstein dairy cows in mid-lactation were used in a randomized block design. The experimental period lasted 84 days. The treatments were: a corn silage-based diet fed on drylot; or partial replacement of corn silage with either restricted alfalfa grazing (limited to 4 hours/day) or unrestricted grazing. A rotational grazing system was used and the amount of concentrate fed was the same (4.5 kg of DM/cow/day) for all treatments. Forage availability was 2,338.0 and 1,878.0 kg DM/ha and forage-on-offer was 1.8 and 4.2 kg DM/100 kg LW under restricted or unrestricted grazing, respectively. No difference in milk production/cow/day was observed among treatments. Mean milk production was 25.9±1, 25.8±1 and 25.2±1 liters/cow/day for feedlot, restricted grazing or unrestricted grazing, respectively. Milk production per hectare was 59 liters/day under restricted grazing and 63 liters/day under unrestricted grazing, whereas it was 48 liters/day on drylot. The partial replacement of corn silage by alfalfa grazing did not limit animal performance and was shown to be economically advantageous as compared to drylot feeding.
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