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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

A Novel Approach to Grass-Legume Management

Solomon, Juan Kevin Quamina 01 May 2010 (has links)
A 2-yr grazing study quantified pasture and animal responses of four forage systems (FS) grazed at two stocking rates (SR; 3 or 6 animals ha-1). Using „Marshall? annual ryegrass (Lolium multiflorum Lam.) and „Durana? white clover (Trifolium repens L.), FS treatments included spatially separated grass and legumes within the same paddock (SS), monoculture grass (MG), monoculture legume (ML), and a binary grass and legume mixture (MIX). Annual herbage mass (HM) was similar among FS at high SR (1900 kg ha-1), but at low SR, grass plots had greater HM (2900 vs. 2000 kg ha-1) than plots of legume monocultures. Animals on SS (1.12 kg) had greater average daily gain (ADG) than ML (0.97 kg), but neither was different from MG (1.08 kg) or MIX (1.00 kg). Low SR animals had greater ADG than high SR (1.09 vs. 0.99 kg). These results indicate that SS grazing system can improve pasture productivity.
122

Using fish culture ponds to examine factors affecting larval hybrid striped bass growth and survival

Brumbaugh, Erica Nicole 24 August 2010 (has links)
No description available.
123

Chicken or fish? Do environmental complexity and stocking density impact affective states of broiler chickens and rainbow trout?

Anderson, Mallory G. 30 September 2021 (has links)
In commercial settings, broiler chickens and rainbow trout are housed in barren environments under high stocking densities, due to an emphasis on production efficiency. These monotonous housing conditions do not provide broilers or trout with the ability to perform functional, highly-motivated behaviors and increase their susceptibility to excessive anxiety and fear, resulting in negative affective states and poor animal welfare. Affective state (or emotional state) is a cumulative product of short-term life experiences, ranging from positive to negative. Because affective states are largely influenced by environmental condition, determining animal affective state can provide useful information on how to improve housing conditions in order to ensure positive experiences and good animal welfare. Cognitive processes are closely associated with affective state; a "cognitive bias" occurs when affective state influences aspects of cognition, such as judgement and attention. Animals in positive affective states make optimistically-biased decisions during ambiguous situations, judging the situation as if it will produce a positive outcome, and show less bias towards a perceived threat, responding in a less anxious and calm manner. Animals in negative affective states make pessimistically-biased decisions during ambiguous situations, judging the situation as if it will result in a negative outcome. Additionally, animals in negative affective states will bias their attention towards a perceived threat rather than alternative stimuli, responding in an anxious manner. Therefore, judgement and attention bias tests can be used to determine animal affective states. In Chapter 3, a judgement bias test was used to determine affective state of broiler chickens housed in either complex (perches, dust bath, pecking stones, and rotating enrichment objects) or barren (no enrichment) environments under either high or low stocking densities. Broilers housed in complex environments responded more optimistically during the judgement bias test than broilers from barren environments, indicating the former were in a positive affective state. Stocking density did not impact their responses in the judgement bias test, indicating that affective states were not impacted by that treatment. In Chapter 4, an attention bias test was used to determine level of anxiety and a tonic immobility test was used to determine fear in order to investigate affective state of broilers housed in the same conditions as described for Chapter 3. Broilers housed in complex environments were less anxious during the attention bias test than broilers from barren environments, indicating environmental complexity reduced anxiety in broilers. Stocking density did not impact anxiety. Broilers from high stocking density environments had shorter tonic immobility durations than broilers from low stocking density environments, suggesting the former were less fearful. Environmental complexity did not impact fearfulness. In Chapter 5, a judgement bias test was used to determine affective state of rainbow trout housed in either complex (shelter structure and artificial plants) or barren (no enrichment) tanks under either low or high stocking densities. Trout housed in high stocking density tanks responded optimistically during the judgement bias test, indicating they were in a more positive affective state compared to trout housed in low stocking density tanks. Environmental complexity did not impact their responses in the judgement bias test, indicating no effect of enrichments on affective states was found. These results indicate a beneficial relationship of a complex environment on broiler chicken affective state, observed through an optimistic judgement bias and reduced attention bias (anxiety) towards a perceived threat. Thus, providing a complex housing environment for broilers can improve their welfare and result in a positive affective state. Rainbow trout reared at the tested high density resulted in a positive affective state, although complexity did not benefit their welfare. Our results contribute much needed information on stocking densities to ensure fish welfare. Overall, environmental complexity, not stocking density, had a positive impact on broiler chicken affective states. Rainbow trout affective states were positively impacted by stocking density, but not environmental complexity. / Master of Science / Conventional housing of broiler chickens and rainbow trout (both raised for meat) causes concern for their welfare and affective states. Environmental conditions can greatly impact animals' affective states–their long-term emotional state, ranging from positive to negative. In barren environments at high stocking densities, broiler chickens and rainbow trout are prevented from showing normal behaviors and these conditions can compromise their affective state and welfare. By 'asking' chickens and trout whether the glass is half full or half empty, we can determine level of optimism or pessimism, and level of anxiety or calmness, therefore gaining a better understanding of their affective states. This can be done using a judgement bias test and attention bias test, where animal responses (optimism and anxiety) are recorded during ambiguous situations (judgement) and threatening situations (attention). Animals in positive affective states judge ambiguous situations optimistically (glass half full) and pay little attention towards perceived threats, while animals in negative affective states judge the same ambiguous situations pessimistically (glass half empty) and pay more attention towards perceived threats. In Chapter 3, responses to ambiguous situations were used to determine the affective state of broiler chickens housed in either enriched (perches, dust bath, pecking stones, rotating toys) or barren environments at either high or low stocking densities. Broiler chickens housed in enriched environments had an optimistic judgement bias of ambiguous situations (glass half full), suggesting they were in a more positive affective state compared to broilers housed in barren environments. Stocking density did not impact their level of optimism. In Chapter 4, responses to a perceived threat were used to determine level of anxiety and a tonic immobility test was used to determine fear of broilers housed under the same conditions as in Chapter 3. Broilers housed in enriched environments paid less attention to a perceived threat than broilers housed in barren environments, indicating the former were less anxious (glass half full) and in a positive affective state. Fear was not impacted by the tested enrichments, but birds kept under higher stocking densities did show reduced fear compared to birds in low-density environments. In Chapter 5, rainbow trout were housed in either enriched (shelter structure and artificial plants) or barren tanks at either high or low stocking densities. Affective state was evaluated through their responses to ambiguous situations. Trout housed in high stocking density environments had an optimistic judgement bias of ambiguous situations (glass half full), suggesting they were in a more positive affective state than trout housed in low stocking density environments. The enrichments did not impact their responses during the test, suggesting they did not impact fish optimism. These results indicate that an enriched environment improves broiler affective state and welfare compared to conventional housing conditions, the tested densities did not impact their welfare. Although an enriched environment did not positively impact responses of trout during ambiguous situations, our results show that housing rainbow trout in large groups results in a positive affective state and improved welfare status compared to housing trout in small groups. Overall, environmental enrichment, not stocking density, had a positive impact on broiler chicken affective states. Rainbow trout affective states were positively impacted by stocking density, but not environmental enrichment.
124

Assessment of the performance of stocked northern and Florida largemouth bass and their progeny in Briery Creek Lake, Virginia

Hoover, Randall S. 10 October 2009 (has links)
This study examined the suitability of Florida largemouth bass (Micropterus salmoides floridanus) for introduction into Virginia and other mid-latitude waters by comparing the performance of northern (M. s. salmoides), Florida, and hybrid largemouth bass in a 342 ha south-central Virginia reservoir, Briery Creek Lake (BcL). Fingerling northern and Florida largemouth bass were stocked into Briery Creek Lake in 1986, following impoundment, and in 1987. Largemouth bass were collected for genotypic and performance analyses in the autumn and spring beginning in 1989 and ending spring 1991. Electrophoretic analyses demonstrated that hybrid largemouth bass (F1 and Fx) dominated the 1987-1990 cohorts and indicated that one or both founding stocks were genetically impure. Comparisons of electroshock catch composition showed no survival advantage for Florida largemouth bass (FLMB) age-1 and older and no differential vulnerability to angling among the four presumptive genotypes of largemouth bass in Briery Creek Lake. Age-O FLMB proportions declined over both winters (1989-1990 and 1990-1991) indicating relatively high first-mortality in the thermal regime of Briery Creek Lake (3,875 annual mean of heating degree days). Statistical comparisons of growth revealed no consistent differences among the respective bass genotypes, although survival and growth tended to be slightly higher for PI hybrid bass. The average total length of largemouth bass in BCL was below the state's average by age three. Total lengths of age-O FI and northern largemouth bass (NLMB) were higher than FLMB and Fx bass in October, perhaps as a result of earlier spawning among NLMB and between the subspecies. Relative weights of largemouth bass in BCL were generally below 95; and few significant differences in (Wr) were observed among the presumptive largemouth bass genotypes. The suboptimal condition (Wr) of largemouth bass in BCL coupled with the decline in growth and condition of bass with increasing age suggested inadequate prey abundance in Briery Creek Lake. Overall, Florida subspecific alleles did not increase in BCL over time, but the population genetic composition shifted toward an Fx mixture in the 1990 year class; future generations of largemouth bass should be dominated by Fx individuals. Results of this study did not demonstrate substantial performance differences among northern and Florida largemouth bass, and their hybrids, except for poorer first-year survival of the Florida subspecies. Therefore, this study provides no support for the continued introduction of Florida largemouth bass in Virginia or other mid-latitude regions. / Master of Science
125

An evaluation of the techniques used to restock unoccupied wild turkey habitat in Virginia

Cantner, Danford Erld 06 February 2013 (has links)
This investigation of the methods of restocking unoccupied wild turkey habitat in Virginia was conducted primarily to determine the success or failure of the propagation pen program during the 195% breeding season and to compare the success of this type of restocking with restocking programs of other states using wild-trapped turkeys. / Master of Science
126

Materialförsörjningssystemens inverkan på monteringens effektivitet : En studie med fokus på huruvida utformningen av ingående delar i kittning och line stocking kan effektivisera monteringen / The impact of material supply system on assembly efficiency : A study that focus on how different parts in kitting and line stocking can make the assembly more efficient.

Björklund, Sofie, Tuomisto, Emelie January 2020 (has links)
Purpose - What influences the choice of material supply systems as well as how the design of the systems influences the efficiency of the assembly is substantially important. This because the target audience of the study; manufacturing companies whom applies any kind of material supply system, must be able to achieve and maintain a social and economic sustainability. Thus, the study aims to: Increase knowledge of how the choice and arrangement of material supply affects the efficiency of assembly. The purpose has been broken down into three research questions: 1.      Which is the most suitable material supply system depending on various types of factors? 2.     How does the material supply system affect the efficiency of the assembly process? 3.     How should material supply systems be adapted for an efficient assembly process? Method - The purpose of the study and the research questions are based on the problem description that was formulated. An abductive approach has characterized the case study work process. The literature review has formulated by a review of previous research and has together with the data collection methods: interviews, observations and document studies, formed the analysis. In order to provide answers to the study’s research questions, collected data was compared to previous research, in order to find similarities or differences. Result - The choice of material supply system is mainly influenced by applied production strategy, production system and the setup of the assembly. It doesn’t matter how the choice has been made unless a well-functioning information system exists, in terms of efficiency of the assembly. Walking distances as well as the location of components and how they are introduced to the assembler, should also be considered in the design of the material supply systems. That is important due to the value-adding activities performed at the assembly station. Several problems have been identified with the use of Lean tools which contributed to formulated improvement suggestions. Implications – The theoretical contributions of the study covers the inadequate theory that was found when connecting production strategies with the advantages and disadvanatges of material supply systems. Also, most of the theories emphasize how efficiency in assembly lines can be improved with the use of material supply systems, but there is limited information how the design of material supply systems affects the efficiency of assemblers in production cells. Empirically, the study contributes with different stages where various issues and wastes have been identified based on the presentation and the arrangement of the material supply systems. This increases the opportunity to prioritize the issues which should be based on the stages that includes most waste. Likewise, the choice of material supply system can be used as guidelines to find out when each system is most suitable. Limitations - Since data has been collected from only one company, the study's validity can be questioned. In addition, an abductive approach made the study complex as well as time-consuming and contributed to that the intended use of economic models was defaulted. / Syfte – Valet av materialförsörjningssystem påverkas i första hand av olika faktorer. Därtill är systemens utformning av betydelse för monteringens effektivitet. Detta för att studiens målgrupp; tillverkande företag där någon form av materialförsörjningssystem tillämpas ska kunna uppnå och bibehålla en social- samt ekonomisk hållbarhet. Därmed är studiens syfte att: Öka förståelsen för hur valet samt utformningen av materialförsörjningssystem påverkar effektiviteten i montering. Syftet har sedan brutits ned i tre frågeställningar: 1.      Vilket är det mest lämpade materialförsörjningssystemet beroende på olika          påverkansfaktorer? 2.     Hur påverkas materialförsörjningssystem monteringsprocessen effektivitet? 3.     Hur bör materialförsörjningssystem anpassas för en effektiv monteringsprocess? Metod – Studiens syfte samt frågeställningar är baserade på den problemformulering vilken definierades i enlighet med fallföretagets önskemål. En abduktiv ansats har präglat enfallsstudiens arbetsprocess. Litteraturöversikten har formats genom granskning av tidigare forskning och har tillsammans med datainsamlingsmetoderna: intervjuer, observationer samt dokumentstudier utgjort analysavsnittet. För att kunna ge svar på studiens frågeställningar jämfördes insamlad data med tidigare forskning, för att hitta likheter alternativt skillnader. Resultat – Valet av materialförsörjningssystem påverkas främst av respektive produktionsstrategi, produktionssystem samt produktionsupplägg. Det är oväsentligt sett till monteringens effektivitet, hur valet genomförts om inte ett välfungerande informationssystem existerar. Därtill bör hänsyn även tas till gångavstånd samt lokalisering av komponenter vid utformandet av materialförsörjningssystemens upplägg samt presentation. Detta då monteringens värdeskapande arbete ska kunna uppnå största möjliga effektivitet. Flertalet problem identifierades med hjälp av Lean-verktyg vilket möjliggjorde att förbättringsförslag lämnades. Implikationer – Studiens teoretiska bidrag behandlar kopplingen mellan applicerad produktionsstrategi samt materialförsörjningssystemens för- och nackdelar, vilket under studiens arbetsprocess visat sig vara bristfälligt. Likaså framhäver merparten av teorierna hur monteringens effektivitet påverkas i ett line-utformat produktionsupplägg, varav paralleller mellan grupporganiserat produktionsupplägg samt materialförsörjningssystem även utgör studiens teoretiska bidrag. Empiriskt sett bidrar studien med att materialförsörjningens presentation och upplägg delats upp i olika steg där diverse problem samt slösersier identifierats, vilket ökar möjligheterna kring att prioritera bland mest väsentliga problem. Prioriteringen bör utgå från steget, där flest slöserier återfinns. Likaså bidrar valet av materialförsörjningssystem med en guidning kring när respektive system är mest lämpligt att använda. Begränsningar – Då det insamlats data från endast ett företag kan studiens generaliserbarhet ifrågasättas. Dessutom innebar en abduktiv ansats att studien varit komplex samt tidskrävande och bidrog till att nyttjandet av tilltänkta ekonomiska modeller uteblev.
127

Machine Tool Spare Parts Provisioning for Manufacturers: A Study and Application for Industries Engaged in Aluminum Cutting and Shaping

Barker, David W. 12 1900 (has links)
This study identifies the concepts of reliability, cost of downtime, cost of spare parts, and procurement lead time as the four key moderators of spare parts availability. These concepts are used to establish a model to manage spare parts inventories. Reliability was assessed in terms of developing failure predictions for major component categories. Cost of downtime was evaluated by identifying various methods for determining costs associated with downtime. Cost of spare parts was examined to find correlations with economic indicators. These correlations were used to predict future price movements. Yearly changes in lead time were identified and correlated with economic indexes to develop movement predictability.
128

Insuffisance de la régénération naturelle dans les jeunes forêts de feuillus du sud du Québec issues de la déprise agricole

Orangeville, Loïc d' January 2006 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
129

Dinâmica de deposição de fezes em pastagem de Brachiaria brizantha submetida à intensidades de pastejo / Dynamics of feces deposition in Brachiaria brizantha pasture under grazing intensities

Marchesin, Wilson Aparecido 20 January 2006 (has links)
A presente linha de pesquisa objetivou caracterizar a distribuição dos bolos fecais de bovinos depositados em uma pastagem de capim-braquiarão [(Brachiaria brizantha (Hochst ex A. Rich.) Stapf cv. Marandu], sob lotação rotacionada e intensidades de pastejo e verificar as alterações na fertilidade do solo e no acúmulo de foragem. O experimento foi conduzido na Faculdade de Zootecnia e Engenharia de Alimentos - FZEA/USP em pastagem com 25,2 ha, dividida em 80 piquetes de 3150 m². O ciclo de pastejo foi de 35 dias, sendo a ocupação de 7 dias e o período de descanso de 28 dias durante o verão. Os piquetes avaliados eram aqueles utilizados com ofertas de forragem de 5 e 10 % (5 kg de massa de forragem para cada 100 kg de peso animal dia-1). Assim, foram dois tratamentos com quatro blocos (repetições). Em cada piquete avaliado houve a demarcação de três círculos de 12,5 metros de raio. Cada círculo recebeu uma letra (A, B, C) para identificação. Após o período de ocupação de 7 dias houve a contagem dos bolos fecais e o registro do respectivo circulo de ocorrência. Houve a amostragem de fezes para análise da composição em matéria seca, matéria orgânica, matéria mineral, macro e micronutrientes, além da coleta dos dados de peso e da área ocupada pelo bolo fecal. Houve a marcação de áreas em cada piquete, ao lado do bolo fecal, para avaliação de acúmulo de forragem, da fertilidade solo quanto aos nutrientes que retornam ao solo nas profundidades de 0-5, 5-10, 10-15,15-20, 20-25 cm abaixo do bolo fecal. As porcentagens de bolos fecais presentes nas áreas de descanso foram de 33,5 e 18,9% para 5 e 10% OF e de 4,2 e 13,8% para as áreas de rejeição. As áreas cobertas pelos bolos fecais por dia para cada unidade animal nos tratamentos de 5 e 10% OF foram 0,248 e 0,214 m² respectivamente, e que uma unidade animal defeca em média 5,63 e 4,84 vezes ao dia para as OF de 5 e 10%. Os valores de densidade de bolos fecais presentes na pastagem foram de 0,100 e 0,065 bolos fecais por m², nos tratamentos 5 e 10% de OF. Sendo que os valores da porção da pastagem coberta sem e com a sobreposição da pastagem indicando que ao final de um ano a pastagem pode ser coberta de 5,7 a 10,6%. O acúmulo de forragem na pastagem, para os pontos com a presença do bolo fecal, foi da ordem de 685,62 kg de MS/ha e de 242,87kg de MS/ha sem a presença do bolo fecal, portanto, cerca de 2,8 vezes superiores. O número de bolos fecais presentes nas áreas de avaliação é determinado pela taxa de lotação. A sua deposição na área de descanso e de rejeição foi de maneira inversa. Nas ofertas de forragem estudadas durante os anos de 2003-2004, o modelo de distribuição espacial dos bolos fecais foi o agregado e sua contribuição para a fertilidade é concentrada em pequenas áreas. O bolo fecal na oferta de forragem de 5% apresenta maior contato com o solo, portanto teve participação significativa no aumento de pH em superfície, o que contribuiu com a disponibilidade de macro e micronutrientes e com a indisponibilidade de Al. Os macronutrientes primários fósforo e potássio apresentaram-se mais disponíveis no tempo e nas camadas superficiais do solo devido às alterações de pH pela presença do bolo fecal. A área de influência do bolo fecal (fertilidade) teve papel importante para melhorar o acúmulo de forragem na pastagem. No entanto, essa área é concentrada e pontual. / The objective of research was characterize the distribution of bovines dung pats deposited in a palisadegrass pasture [(Brachiaria brizantha (Hochst ex A. Rich.) Stapf cv. Marandu], under rotational stocking and grazing intensities and the influence of dung pats in fertility of soil and the herbage accumulation. The experiment was carried out at Faculdade de Zootecnia e Engenharia de Alimentos - FZEA/USP in a pasture with 25,2 ha, divided in 80 plots with 3150 m². In the grazing cycle of 35 days, 7 days of grazing and 28 days of rest, during the summer. The evaluated plots was the used two levels of herbage allowance 5 and 10% (5 kg of dry matter per 100 kg live weight per day). Them, two treatments with four blocks (repetitions). Each evaluated plots, the ground was located three circles of 12.5 meters of ray. Each circle received a letter (A, B, C) for identification. After 7 days of occupation, dung pats was counting and register in the respective circulate of occurrence. Samples of feces was collected to analysis to determine the dry matter, organic matter, mineral matter, macro and microminerals and data of weight and the area covered by dung pats. Each plots, areas was located the side of the dung pats, to evaluation of the herbage accumulation, and the fertility of soil and nutrients that return in the depths of 0-5; 5-10; 10-15;15-20; 20-25 cm under of the dung pats. The dung pats percentage in resting areas was 33.5 and 18.9% to 5 end 10% HA and the 4.2 and 13.8% to reject areas. Covered areas by animal unit dung pats by day was 0.248 and 0.214 m² to treatments of 5 and 10% HA respectively, a animal unit deposit feces 5.63 and 4.84 times by day to the HA of 5 and 10%. The values of density in the pasture was 0.100 and 0.065 dung pats by m², in the treatments of 5 e 10% of HA. And the portion of pasture covered in one year can be 5.7 to 10.6%. The herbage accumulation in the pasture, in area with the dung pats was 685.62 de DM/ha and the 242.87 kg DM/ha without the dung pats. The number of dung pats presents in areas of evaluation is determinates by stocking rate. Its deposition in resting areas and the reject areas are different. In the herbage allowance studded during the years 2003-2004, the spatial model distribution of dung pats was aggregate, and contribution to the soil fertility is concentrated in small areas. The dung pats in herbage allowance of 5% had more contact with the soil, had participation in the increase of pH in surface, change the available of micro and macronutrients. The primary macronutrients phosphorus and potassium more available in the time and the layer of the soil due the alteration of the pH. The influence area to the dung pats (fertility) had important contribution to the herbage accumulation in the pasture, but this area is concentrated and small.
130

Interceptação luminosa, massa de raízes e acúmulo de forragem em Arachis pintoi cv. Belmonte submetido a intensidades de pastejo / Light interception, root mass and herbage accumulation in Arachis pintoi cv. Belmonte subjected to intensities of grazing

Carvalho, Lucas da Rocha 12 February 2014 (has links)
Atualmente, o termo sustentabilidade vem ganhando destaque dentro das atividades agrícolas e para a produção animal em pastagens não é diferente. As leguminosas forrageiras são conhecidas por algumas características peculiares como grande capacidade de fixação do nitrogênio atmosférico e elevado valor nutritivo, surgindo assim como uma alternativa viável nesse novo modelo de produção. Entretanto, muitas vezes práticas de manejo inadequadas acabam não permitindo a exploração do potencial dessas espécies, levando-as ao desuso. Dessa forma, conhecer a resposta de plantas (alterações em forma e função) a intensidades de pastejo é imprescindível para permitir a idealização de estratégias de manejo eficientes que possam contribuir para a otimização do processo produtivo em sistemas pastoris. Este trabalho fez parte de uma série de experimentos delineados com o propósito de avaliar aspectos gerais de crescimento e desenvolvimento do amendoim forrageiro sob pastejo e suas implicações sobre a produção de forragem e potencial de consumo pelos animais. Seu objetivo específico foi avaliar as características produtivas de Arachis pintoi cv. Belmonte submetido a intensidades de pastejo sob lotação contínua. O experimento foi conduzido na Escola Superior de Agricultura \"Luiz de Queiroz\", Piracicaba, SP, de janeiro a dezembro de 2013. Os tratamentos corresponderam a intensidades de pastejo determinadas por alturas de manejo do pasto (5, 10, 15 e 20 cm), e foram alocados às unidades experimentais (piquetes de aproximadamente 200 m²) segundo delineamento de blocos completos casualizados, com quatro repetições. Foram caracterizadas e determinadas as seguintes variáveis-resposta: índice de área foliar, ângulo da folhagem, interceptação luminosa do dossel, massa de forragem e sua composição botânica e morfológica, número e massa de nódulos radiculares, massa de raízes e acúmulo de forragem. As intensidades de pastejo promoveram alterações no crescimento e desenvolvimento do Arachis pintoi cv. Belmonte. Pastos manejados com intensidade de pastejo mais leniente (15 e 20 cm) apresentaram maior índice de área foliar, ângulo da folhagem, massa de forragem, porcentagem de plantas invasoras e taxa de acúmulo de forragem (exceto no inverno). Em contrapartida, pastejos severos (5 e 10 cm) proporcionaram maiores valores de porcentagem de folíolos e pecíolos, relação folíolo/estolão, número e massa de nódulos, massa de raízes e taxa de acúmulo de forragem durante o inverno. A intensidade de pastejo não afetou o peso médio dos nódulos, somente o seu número e massa total. Outros aspectos produtivos apresentaram efeitos isolados de época do ano como porcentagem de estolão e de material morto, com maiores valores registrados no verão e no inverno, respectivamente. Estolões assim como folhas (folíolos e pecíolos) corresponderam às principais estruturas na determinação do crescimento das plantas, tendo sido afetados de forma direta pela intensidade de pastejo e época do ano. A intensidade de pastejo interferiu com a relação parte aérea/raízes, de forma que maior massa de raízes e de nódulos foram registradas nos pastos manejados a 5 e 10 cm e o maior IAF, interceptação de luz e acúmulo de forragem foram registrados nos pastos manejados a 15 e 20 cm. O fato indica uma relação de compensação entre número e massa de nódulos/raízes e IAF controlando o acúmulo de forragem, revelando grande plasticidade fenotípica potencial dessa planta forrageira e potencial de uso em pastagens. / In recent years the term sustainability is becoming increasingly important in agriculture, including animal production from pastoral systems. Forage legumes are known for some particular characteristics like large capacity for capturing atmospheric nitrogen and high nutritive value of the produced herbage, and for that reason is being considered as a viable alternative in this new production model. However, inadequate management practices often result in no realisation and exploitation of their production potential, resulting in low use of these plant species. For that reason, understanding of plant responses (modifications in form and function) to intensities of grazing is essential for allowing planning of efficient management practices aiming at optimising productivity in pastoral systems of animal production. This study was part of a series of experiments conceived with the purpose of evaluating general aspects of growth and development of forage peanut under grazing and their implications to herbage production and potential of herbage intake by grazing animals. The specific objective was to evaluate the agronomic characteristics of Arachis pintoi cv. Belmonte subjected to intensities of grazing under continuous stocking. The experiment was carried out at Escola Superior de Agricultura \"Luiz de Queiroz\", Piracicaba, SP, from January to December 2013. Treatments corresponded to four intensities of grazing characterised by the sward management heights of 5, 10, 15 and 20 cm. These were allocated to the experimental units (200 m2 paddocks) according to a randomised complete block design, with four replications. The following response variables were evaluated: sward leaf area index (LAI), foliage angle, canopy light interception (LI), herbage mass and its morphological and botanical composition, number and mass of root nodules, root mass and herbage accumulation. The grazing intensities interfered with growth and development of Arachis pintoi cv. Belmonte. Swards managed at 15 and 20 cm showed higher LAI, foliage angle, herbage mass, percentage of weeds and herbage accumulation rates (except in winter) than those managed at 5 and 10 cm. On the other hand, swards managed at 5 and 10 cm showed higher percentage of leaf, leaf-to-stolon ratio, number and mass of root nodules, root mass and winter herbage accumulation rates. Grazing intensity did not affect average nodule weight, only nodule number and total mass. Other productive aspects revealed isolated effects of season of the year like percentages of stolon and dead material, with larger values recorded during summer and winter, respectively. Stolons as well as leaves corresponded to the main structures determining plant growth, and were directly affected by grazing intensity and season of the year. Grazing intensity interfered with the shoot-to-root ratio, with larger root and nodule mass being recorded on swards managed at 5 and 10 cm and larger LAI, LI and herbage accumulation recorded on swards managed at 15 and 20 cm. The fact indicates a compensating relationship between number and mass of nodules/roots and LAI controlling herbage accumulation, highlighting the large potential phonotypical plasticity of this forage plant and potential of use in pastures.

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