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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.
11

Métodos de pastejo: produção vegetal e animal / Grazing methods: vegetal and animal production

Rocha, Cesar Oliveira 20 February 2014 (has links)
As pesquisas com métodos de pastejo têm culminado em divergência de resultados no desempenho de plantas e animais. As diferenças quantitativas e qualitativas entre métodos de pastejo poderiam ser elucidadas se estes fossem comparados, considerando o manejo ideal proposto para cada método. O objetivo do presente trabalho foi comparar métodos de pastejo, manejados com diferentes estratégias. O delineamento experimental utilizado foi em blocos completos e casualizados com 3 tratamentos e 3 repetições. Os tratamentos consistiram em três métodos de pastejo: lotação rotativa, utilizando altura do dossel como critério de manejo (AL); lotação rotativa, utilizando oferta de forragem como critério de manejo (OF); lotação contínua, mantida a 18 cm de altura (CO). O experimento foi realizado em área total de 25,2 hectares, formada com Brachiaria brizantha cv. Marandu localizada na Faculdade de Zootecnia e Engenharia de Alimentos da Universidade de São Paulo, em Pirassununga-SP. O período experimental de 93 dias, compreendido entre 15 de dezembro de 2011 e 15 de março de 2012 foi dividido em 3 períodos de avaliações. As variáveis foram comparadas pelo teste de Tukey a 10% de significância. Foram observadas interações entre tratamentos e períodos de avaliação para a maioria das respostas relacionadas à planta forrageira bem como para desempenho e taxa de lotação. O teor de proteína bruta não foi afetado pelos métodos de pastejo, porém, o teor de fibra em detergente neutro foi maior para o tratamento AL. A produtividade não foi afetada pelos métodos de pastejo. Assim, o método de lotação contínua é o mais atrativo com produtividade semelhante aos demais. / Research comparing grazing methods have resulted in conflicting findings on forage and animal performance. Quantitative and qualitative differences between grazing methods could be elucidated whether the methods are compared considering the ideal management proposed for each method. The objective of this study was to compare grazing methods, managed with different strategies. The experimental design was randomized complete blocks, with three treatments and three replications. Treatments consisted in three grazing methods: rotational stocking using canopy height as a management criteria (AL), rotational stocking using forage allowance as a management criteria (OF), continuous stocking held at 18 cm height (CO).The experiment was conducted in a total area of 25.2 hectares, planted with Brachiaria brizantha cv. Marandu, located at the Faculty of Animal Science and Food Engineering, University of São Paulo, in Pirassununga - SP. The 93 days experimental period, from December 15th of 2011 to March 15th of 2012, was divided into three assessment periods. The variables were compared by the Tukey test at 10% significance. Interaction between treatments and assessment periods were observed in the most of the variables related to forage plant as well as animal performance and stocking rate. Crude protein concentration was not affected by grazing methods, although the neuter detergent fiber was greater to AL treatment. Productivity was not affected by grazing methods. Thus, continuous stocking method is the most attractive, with similar productivity to the others.
12

Komparace skladových technologií pro zásobování výroby u vybraných průmyslových podniků / The comparison of stocking technologies for supply production in industrial companies

KOUTNÝ, Stanislav January 2010 (has links)
The theme of my work is central stocking. My work is dealing with central stocking on the basis of literary sources in theory. On account of theoretical prepared structure it analyses central stocking in two manufacturing corporation which are settled in Czech Republic and pursue a comparison of gained outcomes. In theoretical part is stocking included in broader framework of whole problems of organization. Also are supposed thesis of the importance and character of execution of stocking compared to its costs, central stocking is determinate (beside not central) and its main competence are more closely explained. Central stocking is analyses in bigger detail by processing access which is inspired by a structure of the process according to ISO 9001. A separate range and content of central stocking is translated in light of stocking equipment and stocking processes. In practical part two companies were analyzed and compared in particular regard. By this was given knowledge of the single stocking systems and thanks to that coherent knowledge their conformity and contrasts. In the part of discussion are claimed the most significant common ascertained agreements and differences and the most important references are made in relation to surveyed stocking systems. A conclusion of my work summarizes principal differences which were found in profession part of stocking systems of compared subjects and resumes the need of harmonization of all coherent component of the system.
13

Métodos de pastejo: produção vegetal e animal / Grazing methods: vegetal and animal production

Cesar Oliveira Rocha 20 February 2014 (has links)
As pesquisas com métodos de pastejo têm culminado em divergência de resultados no desempenho de plantas e animais. As diferenças quantitativas e qualitativas entre métodos de pastejo poderiam ser elucidadas se estes fossem comparados, considerando o manejo ideal proposto para cada método. O objetivo do presente trabalho foi comparar métodos de pastejo, manejados com diferentes estratégias. O delineamento experimental utilizado foi em blocos completos e casualizados com 3 tratamentos e 3 repetições. Os tratamentos consistiram em três métodos de pastejo: lotação rotativa, utilizando altura do dossel como critério de manejo (AL); lotação rotativa, utilizando oferta de forragem como critério de manejo (OF); lotação contínua, mantida a 18 cm de altura (CO). O experimento foi realizado em área total de 25,2 hectares, formada com Brachiaria brizantha cv. Marandu localizada na Faculdade de Zootecnia e Engenharia de Alimentos da Universidade de São Paulo, em Pirassununga-SP. O período experimental de 93 dias, compreendido entre 15 de dezembro de 2011 e 15 de março de 2012 foi dividido em 3 períodos de avaliações. As variáveis foram comparadas pelo teste de Tukey a 10% de significância. Foram observadas interações entre tratamentos e períodos de avaliação para a maioria das respostas relacionadas à planta forrageira bem como para desempenho e taxa de lotação. O teor de proteína bruta não foi afetado pelos métodos de pastejo, porém, o teor de fibra em detergente neutro foi maior para o tratamento AL. A produtividade não foi afetada pelos métodos de pastejo. Assim, o método de lotação contínua é o mais atrativo com produtividade semelhante aos demais. / Research comparing grazing methods have resulted in conflicting findings on forage and animal performance. Quantitative and qualitative differences between grazing methods could be elucidated whether the methods are compared considering the ideal management proposed for each method. The objective of this study was to compare grazing methods, managed with different strategies. The experimental design was randomized complete blocks, with three treatments and three replications. Treatments consisted in three grazing methods: rotational stocking using canopy height as a management criteria (AL), rotational stocking using forage allowance as a management criteria (OF), continuous stocking held at 18 cm height (CO).The experiment was conducted in a total area of 25.2 hectares, planted with Brachiaria brizantha cv. Marandu, located at the Faculty of Animal Science and Food Engineering, University of São Paulo, in Pirassununga - SP. The 93 days experimental period, from December 15th of 2011 to March 15th of 2012, was divided into three assessment periods. The variables were compared by the Tukey test at 10% significance. Interaction between treatments and assessment periods were observed in the most of the variables related to forage plant as well as animal performance and stocking rate. Crude protein concentration was not affected by grazing methods, although the neuter detergent fiber was greater to AL treatment. Productivity was not affected by grazing methods. Thus, continuous stocking method is the most attractive, with similar productivity to the others.
14

The genetic effect of stocking and population structure of brook trout (Salvelinus fontinalis) in the Beef River /

Callen, Kevin. January 1983 (has links)
Thesis (M.S.)--University of Wisconsin -- La Crosse, 1983. / Includes bibliographical references (leaves 66-70).
15

Spatial Distribution of Neutral Genetic Variation in a Wide Ranging Anadromous Clupeid, the American Shad (Alosa sapidissima)

Hasselman, Daniel Jmaes 26 May 2010 (has links)
Species long-term persistence is to a great extent contingent on the ability of populations to mount variable responses to perturbations; the breadths of which are largely dependent on the amount of heritable variation present at the population level. However, populations are not necessarily equivalent in their amount of genetic variation, or in their responses to future environmental conditions, and information about the magnitude and spatial distribution of intraspecific genetic variation is integral to conservation planning, and preserving species evolutionary potential. Using neutral molecular markers, I demonstrate that latitude is an important determinant of the amount and spatial distribution of genetic variation within and among Nearctic fishes. Latitudinal declines observed among species were mirrored by declines within species, and encourage a cautionary approach for interspecific comparisons and inferences of broad spatial patterns of genetic variation when data for individual species are obtained from only a portion of their range. I subsequently examined the magnitude and spatial distribution of microsatellite based variation for 33 spawning runs from across the range of American shad (Alosa sapidissima). Sequential reductions of intraspecific genetic variation with latitude were observed among spawning runs from formerly glaciated regions; consistent with stepwise post-glacial range expansion, and successive population founder events. Canadian populations exhibited temporally stable genetic differentiation characterized by a significant pattern of isolation by distance, and exhibited evidence of metapopulation structure. Although isolation by distance was observed among U.S. spawning runs, population structure was comparatively weak; a possible consequence of increased levels of gene flow (human-mediated or natural). Different spatial patterns of population structure were detected across the species’ range, but are not likely due to alternative reproductive strategies (iteroparity vs. semelparity). Rather, these different patterns probably reflect different management strategies in Canada (no stocking) and the United States (stocking), alternative glacial histories, or combinations thereof. Reciprocal patterns of genetic diversity and differentiation observed across the species’ range suggests that U.S spawning runs contribute more to diversity and less to differentiation than Canadian spawning runs. These results have implications for future shad restoration efforts, and the long-term persistence of the species.
16

Effects of fish introductions on the geographic distribution and native invertebrate biodiversity of naturally fishless lakes in Maine /

Schilling, Emily Gaenzle, January 2008 (has links)
Thesis (Ph.D.) in Ecology and Environmental Science--University of Maine, 2008. / Includes vita. Includes bibliographical references (leaves 115-130).
17

Genetic impacts of broodstock selection strategies for Wisconsin's wild brook trout stocking program /

Hughes, Michael S. January 2008 (has links) (PDF)
Thesis (M.S.)--University of Wisconsin--Stevens Point, 2008 / Submitted in partial fulfillment of the requirements of the degree of Master of Science in Natural Resources (Fisheries), College of Natural Resources. Includes bibliographical references (leaves 50-57).
18

The development of test procedures for controlling the quality of the manufacture of engineered compression stockings

Moghaddassian Shahidi, Arash January 2010 (has links)
A new technology platform known as 'Scan2Knit' was invented in the William Lee innovation Centre of the University of Manchester to engineer and manufacture compression stockings for the treatment of venous disease in a Welcome Trust funded research project. The intellectual property of the above technology has been licensed for commercial exploitation by the University.The graduated pressure profile that is necessary for the treatment of venous ulcers is generated with the engineered compression stocking, and will depend on the stitch length of the knitted fabric structure and an empirical pressure profile database. The 'Scan2Knit' technology was developed to produce an engineered compression stocking on a 18 gauge Stoll CMS computerised flat-bed knitting machine utilising a microprocessor controlled precision positive yarn delivery system to guarantee the delivery of a predetermined stitch length to the knitting needles. However, the licensee of the technology has decided to manufacture engineered compressions stockings by using 14 gauge Stoll CMS flat-bed knitting machines instead of gauge 18 machines due to commercial advantages. Therefore, the main aim of this work is to investigate the transfer of 'Scan2Knit' technology on to a coarse gauge manufacturing platform to produce engineered compression stockings. The investigation focuses on two vital requirements of 'Scan2Knit' technology; the analysis of the performance of the precision positive yarn delivery system on the new production platform and the evaluation of the functionality of the knitted structure produced with it. The objectives of the research are to develop test procedures for the evaluation of the three dimensional pressure characteristic of compression stockings manufactured on the new production platform, and the performance of the precision yarn delivery system. To produce the engineered compression stockings with the 'Scan2Knit' technology, it is essential to determine the interface pressure that the knitted structure would impart on a particular radius of curvature at a predetermined strain percentage which is attained with an empirical database. Hence, a key objective of this study is to develop a methodology, which is efficient and user friendly, for the generation of the empirical pressure profile database required to engineer the interface pressure profile of a compression stocking.It is envisioned that the manufacturer of the engineered compression stockings would benefit by the knowledge generated within this research, and develop their own quality assurance procedures to guarantee that the compression stockings are produced to deliver the graduated pressure profile prescribed by the clinician for the treatment of venous ulcers.
19

The impacts of indigenous herbivore grazing over five years (2004 - 2008) on vegetation dynamics in four distinct vegetation types of the winter-rainfall Little Karoo

Madden, Christine 02 February 2017 (has links)
Vegetation in semi-arid regions is subject to change when heavily utilised by herbivores. Changes in species richness, species and growth form composition, total cover and plant palatability in response to rest (fenced) and grazing (open) treatments was investigated in Sanbona Wildlife Reserve over five years (2004-2008). This reserve is over 55 000 ha and has four dominant vegetation types: Little Karoo Quartz Vygieveld, Western Little Karoo, Montagu Shale Renosterveld and previously transformed Renosterveld classified here as Old Lands. There was no significant change in vegetation dynamics between the fenced or open plots. There were significant differences between years in some vegetation types. All vegetation types showed both treatments having similar shifts in floristic composition. Floristic composition deviated the greatest in 2008 in all vegetation types. This was attributed to an increase in summer and winter rainfall in 2008, as all plots were similarly affected. There was no observed impact of herbivores although disturbance from small rodents and baboons was observed in a few plots. The lack of detectable difference between the fenced and open sites was attributed to low stocking rates, good rainfall and insufficient time.
20

Effect of Trailer Stocking Density on Cattle Behavior during Truck Transport

Jury, Lyndi L'Rae 11 May 2013 (has links)
This experiment was conducted to assess the effects of either low or high trailer stocking density (SD) on cattle behavior. British x Continental steers (n = 200; mean BW = 361.53 ± 54.4 kg) were loaded onto one of two truck-towed trailers. Steer behavior and positional orientation were recorded by video camera (8 h). Aggressive behaviors were more frequent (P < 0.0001) in low (178 ± 34.46 kg BW/m2) than high (333 ± 31.84 kg BW/m2) SD. Chin-resting occurred more often (P < 0.05) in low SD, yet there was no difference (P = 0.98) between SD for mounting. There was a SD × trip effect for loss of balance (P < 0.05), ruminating (P < 0.0001), and lying behaviors (P < 0.0001). At both SD, side-left and side-right were the preferred (P < 0.05) standing orientations. These results suggest that SD can affect cattle behavior and orientation en route.

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