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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.
271

An investigation of methods to predict rumen fermentation products from in vivo measurements

Brown, V. E. January 2001 (has links)
No description available.
272

Corn and forage sorghum yield and water use in Western Kansas

Waite, Jason January 1900 (has links)
Doctor of Philosophy / Department of Agronomy / P.V. Vara Prasad / The Ogallala Aquifer is a large underground water source located under the High Plains and is used as the primary irrigation source for producers in the region. Hyper-extraction of the Ogallala is causing a reduction in irrigation capacity for a large part of the region. Confined animal feeding operations in western Kansas rely upon irrigated crops, mainly corn [Zea mays (L.)] as a source of feed. Research has shown that forage sorghum [Sorghum bicolor (L.) Monech] could meet the demands of the confined animal feeding operations while using less water than corn. An experiment was designed to evaluate corn and forage sorghum in Western Kansas. The objective of this research was to evaluate the water use and growth characteristics of irrigated and dryland corn and forage sorghum. Field experiments were conducted at two locations (Tribune Experiment Station, Tribune and a cooperator’s field near Hoxie, Sheridan County Kansas) in 2011-2013. The experimental design at Tribune was a randomized complete block with four replications. A traditional replicated design was not possible at Hoxie. Multiple subsamples per plot were obtained and data are reported as means with standard errors. Corn and forage sorghum were grown under both dryland and fully irrigated conditions at both locations. Neutron access tubes were installed to monitor soil water. Aboveground biomass, intercepted solar radiation and volumetric soil water content were recorded at 5 sampling dates each growing season. Water use was similar between irrigated corn and forage sorghum. There were differences in biomass from year to year between the irrigated crops. Dryland water use was similar between the two crops and also had differences in biomass from year to year. Yields were significantly lower than average for all crops in 2012 due to drought conditions. Solar radiation interception correlated with aboveground biomass measurements. Aboveground biomass from the forage sorghum and corn was ensiled both years and analyzed for nutrient composition. This research suggests that forage sorghum silage may be an acceptable replacement for corn silage in areas with reduced irrigation capacities.
273

Mitigation of condensed tannins found in sericea lespedeza (Lespedza cuneata)

Eckerle, Gregory J. January 1900 (has links)
Doctor of Philosophy / Department of Animal Sciences and Industry / K.C. Olson / Sericea lespedeza (SL; Lespedeza cuneata) is classified as an invasive plant throughout the Great Plains. It infests over 600,000 acres in Kansas. Increasing grazing pressure on SL may reduce seed production and slow the spread of the plant; however, intake of SL by grazing beef cattle is poor, due to the presence of tannins in the plant. Condensed tannins reduce protein digestion by ruminants and may also decrease plant palatability. Detailed study of the appetite-suppressing effects of SL under controlled conditions is essential in order to develop appropriate strategies to increase grazing pressure on this plant. Such information could lead to a degree of biological control of this noxious weed using domestic herbivores. We compared intakes of tallgrass prairie hay by beef cows when hay was either uncontaminated or heavily contaminated by SL. Beef cows fed contaminated hay exhibited a profound aversion to compared to similar uncontaminated hay. Furthermore, differences in voluntary DMI between contaminated and uncontaminated hays of similar chemical composition were manifested rapidly after introduction of contaminated hay into beef cow diets. Supplementation with corn steep liquor (CSL) increased tolerance of beef cows for SL. It ameliorated the negative consequences of tannin consumption in a dose-dependent manner when fed to beef cows in confinement. The beef cows in our study had only limited opportunity to selectively avoid SL because it was offered in chopped form and in a mixture with other forage species. It was unknown if beef cattle supplemented with CSL would readily consume forage contaminated by SL when uncontaminated forage was available simultaneously. Therefore, we examined the effects of CSL fed to beef cows on voluntary selection of tallgrass prairie hay contaminated by SL when uncontaminated tallgrass prairie hay was also available. Supplemental CSL (0.6 kg DM/d) increased both acceptance of and tolerance for SL by beef cows. It ameliorated some of the negative consequences of tannin consumption on digestible DM intake. In addition, voluntary consumption of SL-contaminated forage increased by 25% in supplemented vs. unsupplemented beef cows. It is unknown if supplemental CSL can promote voluntary selection of actively-growing SL by beef cattle grazing native rangeland in the Kansas Flint Hills.
274

Bundle sheath suberin layer as a barrier to rumen microbial degradation in indiangrass and big bluestem leaf blades

Hastert, Arthur A. January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
275

Key resource areas and management of buffalo (syncerus caffer caffer) on Molemane Eye Nature Reserve

Leitner, Peter Ewald 30 April 2013 (has links)
A research report submitted to the Faculty of Science, University of the Witwatersrand, in partial fulfillment of the requirements for the degree of Master of Science (Environmental Sciences) Johannesburg, South Africa 7 February 2013 / In 2004 Molemane Eye Nature Reserve was stocked with 46 disease-free buffalo with the intention of generating sustainable revenues for the Reserve. However, the buffalo’s poor population growth rate and poor body condition during the dry seasons led to management reducing the buffalo population to 21 animals in 2010. The buffalo’s poor performance has drawn the attention to the potential nutritional limitations of the forage available during the dry season and to the importance of key resource areas. I examined the nutritional content of the buffalo forage using faecal analyses as proxy for nitrogen (N) and phosphorus (P), expecting a nutritional stress towards the latter part of the dry season. Data from the GPS/GSM collar on one of the buffalo cows was used to determine the dry season vegetation type selection and to identify key resource areas. A comparison of veld conditions was also done on the lowland vegetation types on Molemane Eye Nature Reserve and an adjacent property (Eye Area), which was earmarked for incorporation, to determine whether veld restoration work was required prior incorporation. It was established that the extended period of poor forage quality during the 2010 dry season was an important limiting factor for the buffalo as the forage quality dropped below the buffalo minimum nutritional requirements (Nf < 1.52 %, Pf < 2 %). A faecal sampling during early 2011 indicated that the nutritional stress period may last as long as 5 months (April to August). The buffalo did not select the vegetation types in proportional to their availability and narrowed their selection as the dry season progressed, preferring those containing woody elements. Of the 8 vegetation types indentified as key resource areas for buffalo during the dry season, the Eye Area holds 4 and contributes less than 5% to the key resource area already available on Molemane Eye Nature Reserve. The overall veld condition of the two areas was similar and no veld restoration work was deemed necessary. Although the incorporation of the Eye Area will shorten the distance between water and forage areas and have some nutritional benefits for buffalo in the dry season, mineral supplementation will be necessary for these valuable animals to become more productive and contribute to the economic objectives of Molemane Eye Nature Reserve.
276

Capim-marandu e babaçu em sistema silvipastoril /

Gazolla, Afrânio Gonçalves. January 2012 (has links)
Orientador: Ricardo Andrade Reis / Banca: Cledson Augusto Garcia / Banca: Paola Pedroso Vantini / Banca: Ana Claudia Ruggieri / Banca: Euclides Braga Malheiros / Resumo: O trabalho objetivou avaliar efeito do babaçu (Attalea speciosa Mart.) sobre os aspectos de: produção de sombra, presença de plantas daninhas, área de solo nu, massa e composição química do pasto de capim-marandu (Brachiaria brizantha cv. Marandu) nos períodos de maior e menor disponibilidade de água, mantido sobre pastejo intermitente, com período de descanso de 30 dias no período das águas e 60 dias no período seco, utilizando a técnica de "mob-stocking". O experimento foi conduzido de setembro de 2010 a setembro de 2011, na Fazenda Santo Antonio em Matinha - MA. A área experimental foi dividida em seis piquetes com as respectivas densidades: 10, 20, 30, 40, 50 e 60 palmeiras por hectare. O delineamento experimental foi formado por parcelas sub-divididas, tendo nas parcelas um fatorial 2 x 6 (dois períodos e seis densidades) e nas sub-parcelas o sombreamento (sombra e sol) com quatro repetições cada. No período das águas o aumento da densidade de palmeiras de babaçu (Attalea speciosa Mart.) em linhas gerais: reduziu à proteína bruta, a porcentagem do solo nu, aumentou a matéria seca da forragem e a umidade do solo. No período seco, o aumento da densidade de palmeiras de babaçu reduziu a proteína bruta e a porcentagem do solo nu. Nas áreas sombreadas o aumento da densidade de palmeiras contribuiu para maiores teores de umidade. O porte elevado das palmeiras de babaçu reduziu o efeito do sombreamento como fator de inibição do desenvolvimento do capim-marandu. A massa seca de capim-marandu foi maior no período das águas e no período seco a massa seca de plantas daninhas, onde o babaçu em sua fase inicial e o capim-duro (Paspalum virgatum) tiveram respectivamente maior participação. O aumento das densidades de palmeiras de babaçu reduziu a massa de plantas invasoras ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The study aimed to evaluate and measure the effect of babassu (Attalea speciosa Mart) in the following aspects of: shade production, weeds, bare soil area, herbage mass, chemical composition of the marandu grass (Brachiaria brizantha cv. Marandu) during periods of greater and lesser availability of water, kept on rotational grazing with rest period of 30 days during the rainy season and 60 days in the dry season, using "mob-stocking" technique. The experiment was conducted from September, 2010 to September, 2011 in Matinha - MA. The experimental area was splitted into six areas with the following densities: 10, 20, 30, 40, 50 and 60 palms per hectare. The experimental design was split-plot having a 2 x 6 factorial (two seasons and six densities) and the shadowing sub-plot (shadow and sun) with four replications. On the rainy season the density increments of the babassu palms (Attalea speciosa Mart.) in general: reduced the crude protein, bare soil percentage, increased the forage dry matter and the soil humidity. In the dry season, the density increments of the babassu palms reduced the crude protein and the bare soil amount. In the shadowing areas the density increments of the babassu palms contributed to increase the soil humidity. The high size of the babassu palms reduced the effect of shadowing as inhibition factor of development of marandu grass. The marandu grass matter was greater during the rainy season and on the dry season the weeds, where the young Attalea speciosa Mart. and the Paspalum virgatum had greater participation. The density increments of the babassu palms reduced the weeds matte... (Complete abstract click electronic access below) / Doutor
277

Landskapets heterogenitet och förutsättningar för älg : Finns det samband mellan landskapets variation och fodertillgång i landskapet? / Landscape heterogeneity – Does it affect the forage available for the Swedish Moose population?

Nilsson, Gustaf January 2019 (has links)
The moose population in Sweden is one of the highest in the world. The population have positive impacts on humans but also cause problems such as browsing damages and collisions with traffic. To manage this population in an adaptive and ecological sound way, the managers need to have as much information as possible. The aim of this study was to improve the description of Sweden’s moose management areas regarding available forage for moose. This is done by describing the heterogeneity of the landscape within the moose management areas, which is done by using different landscape indexes. The heterogeneity indexes is then used to analyze if correlation exists between the variation of the landscape and firstly data that describes the available food, secondly data that indicates the moose population density. Multiple regression analysis were done in order to find a model with the indexes that best explains the variation in available forage and moose population indicators.  The results in this study showed a positive correlation between number of moose shot per 1000 hectares and patch richness awhile a negative correlation was found between number of moose shot per 1000 hectares and edge density. Results also showed a negative correlation between both edge density and the patch richness in the landscape with the presence of rowan, sallow, aspen and oak (RASE). Further developments of indexes that describe landscape heterogeneity is needed, but this study may indicate that knowledge of the variation in the landscape might provide useful information on the prerequisites for the Swedish moose population.
278

Developing year-round forage systems for beef cattle in eastern Kansas

Welty, Robert Ernest January 2010 (has links)
Photocopy of typescript. / Digitized by Kansas Correctional Industries
279

Soil and environmental effects on forage quality with respect to grass tetany

Johnson, Mark Galen January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
280

Regrowth of pearl millet

Stephenson, Robert John January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries

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