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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.
141

Silosuotų pašarų kokybės įtaka karvių produktyvumui ir produkcijos kokybei / The influence of quality ensiled forage on the productivity of cows and production quality

Visockas, Edvinas 26 April 2013 (has links)
Darbo tikslas: nustatyti karvėms šertų silosuotų pašarų kokybinius rodiklius, pašarų įtaką melžiamų karvių produktyvumui ir pieno kokybei. Įvertinti racionų ekonominius rodiklius. Darbo uždaviniai: įvertinti melžiamų karvių silosuotus pašarus ir racionų struktūrą. Išanalizuoti silosuotų pašarų kokybės rodiklius. Nustatyti raciono įtaką karvių produktyvumui ir pieno kokybei. Karvių šėrimo racionų ekonominio įvertinimo analizė. Pateikti išvadas ir pasiūlymus. Tyrimui medžiaga rinkta Jonavos raj., X ūkyje. Išanalizavus X ūkio 2011–2012 metų karvėms šertų silosuotų pašarų kokybę, karvių šėrimo racionų sudėtį, maistingumo rodiklius, galima daryti išvadas: žemės ūkio bendrovės karvių banda atitinka vidutinius produktyvumo rodiklius auginant Lietuvos juodmargių veislės karves. Karvės šeriamos viso raciono pašarų mišiniais. Karvėms racionai sudaromi atsižvelgiant į laktacijos tarpsnius, pagal kuriuos karvės suskirstytos į tris grupes. Racionai nekito per analizuojamuosius metus. Išanalizavus silosuotų pašarų kokybės įtaką karvių produktyvumui, galima teigti, kad racionai ūkyje yra subalansuoti. Atlikus pieno tyrimus, 2012 metais, nustatytas 10,07 proc. didesnis tirtų karvių pieno riebumas., lyginant su karvių pieno riebumu 2011 metais. Karvių pieno riebumas 2011 metais buvo 4,17 proc, o 2012 metais 4,59 proc. Pieno baltymingumas tiriamaisiais metais nekito ir išliko per visą tyrimo laikotarpį 3,48 proc. Laktozės kiekis piene: 2011 metais – 4,34 proc., o 2012 metais 4,4 proc. arba 1... [toliau žr. visą tekstą] / The purpose of the work was to identify ensiled forage used to feed cows quality indicators, forage’s influence on cows' productivity and milk quality, and to rate ration’s economic indicators. The task of the work: to assess the silage used to feed dairy cow and their rations’ structure. To analyze the ensiled forage quality indicators. To set the ration influence on cows’ productivity and milk quality. Economic evaluation analysis of cows’ rations. The conclusions and suggestions. The material for the research was collected in Jonava agricultural company X. The analysis of an X during 2011-2012 ensiled forage used to feed cows quality, cows’ feeding ration composition, nutritional indicators, conclusions can be drawn: agriculture company’s average cow herd suits the productivity indicators of Lithuanian Black and White cows. The cows are fed rations of feeding mixtures. Cows’ rations are drawn up on the stages of lactation, by which cows are divided into three groups. Diets did not change during the surveyed year. The analysis of ensiled forage quality on milk production of cows, it can be said that the farm’s rations are balanced. After the milk testing in 2012, it was established, that compared to 2011 (4.17 percent) milk fat content grew of 10,07 percent (4.59 percent in 2012). Milk protein under investigation didn’t change and remained at 3.48 percent. The quantity of lactose: 2011 - 4.34 percent, 2012 - 4.4 percent. Somatic cell count increased in 2012 to 458... [to full text]
142

Fish meal supplementation of high quality grass silage in dairy cows

Pomerleau, Yvan N. January 1997 (has links)
The aim of this study was to maximize good quality grass silage utilization either by supplying a source of rumen undegradable protein or by a reduction of the concentrate in the diet. A randomized incomplete block design was used to evaluate feed intake, milk production and health incidence occurring in fifty-nine Holstein dairy cow (11 primiparous) distributed randomly to receive three different diets between wk 4 and 24 of lactation. The diets were composed of grass silage (predominance of timothy) offered ad libitum supplemented either with a mixture of cereal grains (wheat:barley 50:50) at 100% of recommendations plus soybean meal (Trt 1), or fish meal (Trt 2), or with cereal grains at 75% of recommendations plus fish meal (Trt 3). The grass silage was harvested at an approximate chop length of 8--10 cm, averaged 37.1% DM and was stored in heap silos. / Finally, an economic evaluation of the treatments was done using milk income, feed cost, health cost, and net income. (Abstract shortened by UMI.)
143

An evaluation of the role of ammonia load in the control of food intake by lambs fed fresh and ensiled alfalfa, (Medicago sativa) /

Harrison, Harry January 1994 (has links)
The problem of reduced appetite in ruminants fed silages persists but the factors responsible for reduced intake of silage have not been elucidated. This study was conducted with the objective of testing the hypothesis that ammonia loading in ruminants could suppress appetite. In a 5 x 5 latin square design, sheep were fed alfalfa silage (S), fresh alfalfa (FA), and FA with added equimolar amounts (450 mmol. kg$ sp{-1}$ feed DM) of NH$ sb4$Cl, NH$ sb4$HCO$ sb3$ and urea; the latter was infused directly into the rumen. The silage had a DM content of 33.1%, pH 4.4, and a lactic acid content of 4.3% of DM. Unfermented herbage had a pH of 5.5 and lactic acid content of 0.2% of DM. Digestibility of organic matter (OMD) exceeded 70% for both S and FA. Organic matter intake (OMI), digestible organic matter intake (DOMI), concentration of rumen NH$ sb3$, rumen pH, osmolality and volatile fatty acids (VFAs) did not differ (P $>$ 0.05) among treatment groups. The lack of differences among treatments may have been as a result of a failure to accentuate qualitative and quantitative differences between the FA and S and to raise ammonia in the rumen and peripheral blood to levels that could alter appetite.
144

Timothy and red clover as forage for dairy production : in vitro degradation characteristics and chemical composition /

Hetta, Mårten, January 2004 (has links) (PDF)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniv. / Härtill 4 uppsatser.
145

Einfluss von Roquefortin C auf Tiergesundheit und Lebensmittelqualität bei Wiederkäuern

Tüller, Georg. Unknown Date (has links)
Techn. Universiẗat, Diss., 2006--München.
146

Bioplynové stanice ve vybrané oblasti jižních Čech / Anearobic digestion plants in selected part of South Bohemia

PROCHÁZKOVÁ, Lenka January 2017 (has links)
The theme of this thesis is to assess the current state of biogas business in selected parts of southern Bohemia and the possibilities for its further development. Further processed economy on the example of a selected company and undertake structured interviews with operators of biogas plants. The first research part handles the issue of biomass, biogas, their preparation - what all have to be careful before and during construction, the legislation itsef and its implementation. In the second part analyzes the economics of selected company, which operates the biogas plant. Everything is monitored from the beginning of construction in 2012 until 2016. Each year are evaluated both financially and in terms of input material consumed. The last section is devoted to the questionnaire controlled interview with executives of three companies that operate biogas plant. The questionnaire consists of three parts - before the construction, during the implementation of biogas plants and biogas into the future of business.
147

Características fermentativas e valor nutritivo de silagens de capim-elefante contendo subprodutos do urucum, caju e manga / Chemical and fermentative characteristics of elephant grass silages with annatto by-product

Telles, Margareth Maria January 2006 (has links)
TELLES, Margareth Maria. Características fermentativas e valor nutritivo de silagens de capim-elefante contendo subprodutos do urucum, caju e manga. 2006. 130 f. Tese (doutorado em Zootecnia)- Universidade Federal do Ceará, Fortaleza-CE, 2006. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-04-19T19:32:50Z No. of bitstreams: 1 2006_tese_mmtelles.pdf: 612422 bytes, checksum: c80d63681a855fb7d8cbe000e31df740 (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-05-27T17:42:37Z (GMT) No. of bitstreams: 1 2006_tese_mmtelles.pdf: 612422 bytes, checksum: c80d63681a855fb7d8cbe000e31df740 (MD5) / Made available in DSpace on 2016-05-27T17:42:37Z (GMT). No. of bitstreams: 1 2006_tese_mmtelles.pdf: 612422 bytes, checksum: c80d63681a855fb7d8cbe000e31df740 (MD5) Previous issue date: 2006 / This research was carried out at the Forage Research Sector – NPF/DZ/CCA/UFC. The chemical and fermentative characteristics elephant grass silages with increasing levels of annatto by-product processing (ABP) addition at ensiling were evaluated. The following treatments were used: T1 – Elephant grass silage, T2 - Elephant grass silage with 4% of annatto seed by-product processing (ABP), T3 - Elephant grass silage with 8% of ABP, T4 - Elephant grass silage with 12% of ABP and T5 - Elephant grass silage with 16% of ABP, on a fresh matter basis. A randomized completely design with four replicates was adopted. As experimental silos, plastic drums of 210 L were used. The dry matter (DM), the organic matter (OM), the crude protein (CP), the neutral detergent fiber (NDF), the acid detergent fiber (ADF), the hemicelluloses, the ether extract (EE), the total carbohydrates (TC), the non-fibrous carbohydrates (NFC), the neutral detergent insoluble nitrogen (NDIN,% total N), the acid detergent insoluble nitrogen (ADIN, % total N), the pH values, the ammonia nitrogen (in percentage of the total nitrogen, N-NH3, % total N), the lactic acid, the acetic acid, the butyric acid and the propionic acid levels were determined. A linear increasing effect (P<0.01) of the ABP addition on the DM, OM, CP, EE, NFC, acid propionic levels and on the pH values was verified. There was no significant difference among the silages on the hemicellulose, NDIN (% total N), lactic acid,acetic acid and acid butyric levels. With regard to ADIN (% total N) and N-NH3 (% total N) there was a quadratic effect and to NDF, ADF and TC a decreasing linear effect of the ABP addition was observed. One concludes that ABP improves the chemical and fermentative characteristics of the silages, recommending 16% of addition, in a fresh matter basis, at the elephant grass ensilage. / Esta Pesquisa foi conduzida no Núcleo de Pesquisa em Forragicultura-NPF no Departamento de Zootecnia do Centro de Ciências Agrárias da Universidade Federal do Ceará (UFC), em Fortaleza, CE. Avaliaram-se as características bromatológicas e fermentativas das silagens de capim-elefante contendo níveis crescentes de adição do subproduto do processamento do urucum (SPU), à ensilagem. Foram testados os seguintes tratamentos: T1 – silagem de capim-elefante, T2 – silagem de capimelefante com 4% de SPU, T3 – silagem de capim-elefante com 8% de SPU, T4 – silagem de capim-elefante com 12% de SPU e T5 – silagem de capim-elefante com 16% de SPU, com base na matéria natural. Utilizou-se um delineamento inteiramente casualizado com quatro repetições. Como silos experimentais, foram utilizados tambores plásticos de 210 L. Determinaram-se os teores de matéria seca (MS), matéria orgânica (MO), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), hemicelulose, extrato etéreo (EE), carboidratos totais (CHOT), carboidratos não fibrosos (CNF), nitrogênio insolúvel em detergente neutro (NIDN, % do N total), nitrogênio insolúvel em detergente ácido (NIDA, % do N total), os valores de pH e teores nitrogênio amoniacal (N-NH3, % do N total), ácido lático, acético, propiônico e butírico. Verificou-se efeito linear crescente da adição de SPU sobre os teores de MS, MO, PB, EE, CNF, valor de pH e teor de ácido propiônico. Não foi verificada diferença significativa entre as silagens quanto aos teores hemicelulose, NIDN (% do N total), ácido lático, acético e butírico. Para NIDA (% do N total) e N-NH3 (% do N total) houve efeito quadrático e para FDN, FDA e CHOT observou efeito linear decrescente em função da adição do SPU. Conclui-se que o SPU melhora as características bromatológicas e fermentativas das silagens, recomendando-se a adição de 16%, na matéria natural, no momento da ensilagem do capim-elefante.
148

Desenvolvimento de microrganismos e valor nutritivo de silagens de capim-Tifton 85

Silva, Jussimara Manoela Nascimento [UNESP] 27 November 2002 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2002-11-27Bitstream added on 2014-06-13T20:45:18Z : No. of bitstreams: 1 silva_jmn_dr_jabo.pdf: 226978 bytes, checksum: b750d41fae4be269e3578a4ae3813b74 (MD5) / Objetivou-se estudar o valor nutritivo e desenvolvimento de fungos e de Listeria spp. no capim-Tifton 85 (híbrido de Cynodon, PI 290884 originário da África do Sul com o Tifton 68 (Cynodon nlemfuensis) ensilado sem emurchecimento (umidade 60-70%), submetido a pré-secagem (umidade 40-50%) e com adição ou não de polpa cítrica (5% do peso verde). As amostras foram colhidas na abertura dos silos e aos 15 e 30 dias após a abertura, para avaliação da ocorrência de Listeria spp e de fungos, do padrão de fermentação (pH, N amoniacal, ácidos orgânicos), teores de matéria seca, de proteína bruta, de nitrogênio associado a parede celular, dos constituintes da parede celular e digestibilidade in vitro da matéria seca (DIVMS). Os dados foram analisados segundo o delineamento em blocos completos casualisados, em esquema de parcela subdividida, sendo que nas parcelas foram avaliadas as silagens submetidas ao emurchecimento e uso ou não de polpa cítrica e nas subparcelas os períodos de exposição ao ar, com quatro repetições. Constatou-se a presença de Listeria spp em 65,6% das silagens de alta matéria seca, sendo que destas 10% foram positivas para Listeria monocytogenes. As silagens de alta matéria seca apresentaram pouca estabilidade aeróbia, tendo sido registrado aumento na ocorrência dos fungos Penicillium, Fusarium e Pithomyces com o prolongamento do período de exposição ao ar. Esses resultados evidenciaram o risco potencial que silagens de gramíneas com alto conteúdo de matéria seca pode representar para a saúde dos animais e humanos. Em termos de padrão de fermentação observou-se baixos teores de ácidos orgânicos e de N amoniacal, altos valores de pH, provavelmente devido aos elevados conteúdos de matéria seca causados pelo emurchecimento e adição de polpa cítrica... / This research was conducted to evaluate the nutritive value and fungal and Listeria spp. occurrence of the no wilted (60 to 70% of moisture) and wilted (40 to 50% of moisture) Tifton 85 ensiled with or without citrus pulp (5.0% of the wet weight). The high dry matter silage were harvested, immediately after the silos opening, also 15 and 30 days after the air exposition. It was evaluated the Listeria and fungal occurrences, fermentation characteristics (pH, amoniacal nitrogen, organic acids), values of dry matter, crude protein (CP), neutral detergent insoluble nitrogen (NDIN), acid detergent insoluble nitrogen (ADIN), neutral detergent fiber (NDF), acid detergent fiber (ADF), and in vitro dry matter digestibility (IVDMD). The data were analyzed according to a randomized block design in split plot scheme, being the silages studied in plots and the periods of air exposure in the split plots, with four replications. It was observed Listeria spp in 65.6% of the high dry matter silage samples, and Listeria monocytogenes occurred in 10.0% of these samples. The high dry matter silage was air unstable and Penicillium, Fusarium e Pithomyces occurrence increased during the air exposition period. These data showed the potential risk that the high dry matter grass silage could represent to the animal and human health. In relation to the fermentation characteristics, it was observed lowest values of amoniacal nitrogen, organic acid, and highest pH values, probably due to the high dry matter content of the silage. The high dry matter silage showed lowest N-NH3/N total values, preserving the crude protein content, probably caused by the low Clostridium activity. The NDIN and ADIN contents increased during the air exposition periods, in function of the microorganism's activity, resulted in high temperature of the high dry matter silage... (Complete abstract, access undermentioned eletronic address)
149

Desempenho técnico e econômico da produção de milho e sorgo para silagem e soja em sucessão em sistema irrigado de integração lavoura-pecuária no cerrado

Costa, Nídia Raquel [UNESP] 03 April 2014 (has links) (PDF)
Made available in DSpace on 2014-12-02T11:16:55Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-04-03Bitstream added on 2014-12-02T11:20:54Z : No. of bitstreams: 1 000800423.pdf: 2294054 bytes, checksum: 7311d74ccc63ee9b18c1ca7a7ef3f25b (MD5) / Como alternativa para o aumento da produtividade dos sistemas de produção, com sustentabilidade, surgiu o Sistema de Integração Lavoura-Pecuária sob Plantio Direto. Desta forma, o presente trabalho objetivou avaliar em um LATOSSOLO VERMELHO distrófico, sob condições irrigadas no Cerrado: 1) o desempenho produtivo e a qualidade da silagem produzida em sistemas de produção de milho e sorgo forrageiro consorciados ou em sucessão com Urochloa brizantha cv. Xaraés e Megathyrsus maximum cv. Tanzânia; 2) a cada corte, do outono à primavera, a produtividade de forragem e o seu valor nutritivo por efeito da aplicação ou não de adubação nitrogenada (70 kg ha-1 de N corte-1 – fonte ureia), após a ensilagem; 3) no último corte, verificar além da produtividade de forragem, os teores de macronutrientes e a decomposição da palhada das forrageiras após a dessecação na primavera e efeito sobre a produtividade da soja em sucessão; 4) avaliar durante a condução dos sistemas de produção, as alterações nos atributos químicos e físicos do solo, além do acúmulo de carbono na camada de 0 a 0,20 m, ao final de cada ciclo produtivo; 5) avaliar o desempenho econômico da Integração Lavoura-Pecuária (ILP) sob sistema plantio direto (SPD), visando constatar a sustentabilidade e lucratividade de cada sistema, durante os anos agrícolas de 2010/2011, 2011/2012 e 2012/2013. Constatou-se que os consórcios de milho e sorgo forrageiro com os capins Xaraés e Tanzânia foram viáveis para a produção de silagens em quantidade e qualidade bromatológica, tanto quanto ao cultivo solteiro das culturas, em SPD no Cerrado. A adubação nitrogenada incrementou a produtividade de matéria seca, com melhoria da qualidade bromatológica e nutricional dos capins, independentemente das modalidades de cultivo. Do mesmo modo, os capins Xaraés e Tanzânia, resultaram em adequada cobertura do solo, principalmente ... / As an alternative for increasing productivity of sustainable production systems, the Crop-Livestock Integration System under no-tillage. Thus, the present study aimed to evaluate in an Oxisol under irrigated conditions in the Cerrado region: 1) The performance and quality of silage produced by corn and sorghum production systems, intercropped or not with Urochloa brizantha var. Xaraés and Megathyrsus maximum var. Tanzania; 2) evaluate each harvest, from autumn to spring, the forage yield and nutritional value by the effect of the application or not of nitrogen (70 kg ha-1 N cutting-1 - source of urea), after silage harvest; 3) in the last cut, verify beyond forage productivity, the macronutrient levels and straw decomposition and fodder after spring desiccation and effect on soybean yield in succession; 4) evaluate throughout the systems production, changes in chemical and physical soil properties, besides the accumulation of carbon in the 0 to 0.20 m layer at the end of each production cycle; 5) evaluate the economic performance of the Crop-Livestock Integration (CLI) system under no-tillage (NT), to verify the sustainability and profitability of each system during the agricultural period 2010/2011, 2011/2012 and 2012/2013. It was found that the consortium of corn and sorghum with Xaraés and Tanzania grasses are viable for the production of silage in quantity and chemical composition quality, as much as, the single crop cultivation in no-tillage system in the Cerrado. Nitrogen fertilization increased dry matter yield, with improvement of the chemical and nutritional quality of grasses, regardless of the methods of cultivation. Similarly, the Xaraés and Tanzania grasses, resulted in adequate ground cover, up to 90 days after the management of desiccation and cutting, especially when fertilized with nitrogen. In irrigated conditions in the Cerrado, aiming the increase of soybean yield, it is ...
150

Techniques to increase silage stability and starch availability and the effects of heat stress abatement systems on reducing heat load in dairy cattle

Johnson, Jared R. January 1900 (has links)
Doctor of Philosophy / Department of Animal Sciences and Industry / Micheal J. Brouk / Four studies were conducted that focused either on silage quality parameters or heat abatement systems to improve cow comfort. Study 1 evaluated the effects of treating whole-plant corn at harvest with a dual-purpose commercial silage inoculant containing Lactobacillus buchneri and Lactococcus lactis O224 on fermentation and aerobic stability of corn silage through 32 d of ensiling. Inoculating silage to be fed after minimal storage time (≤ 32 d post-harvest) had no effect (P > 0.05) on the chemical composition, fermentation variables, aerobic stability or rise in temperature post-harvest. Study 2 was designed to develop a berry processing score (BPS) for sorghum silage as well as evaluate the change in starch digestibility as the level of berry processing increased. A method to evaluate the level of processing in sorghum silage was successfully developed by measuring the percent of starch passing through a 1.7 mm screen. This provides the industry with a standardized method to measure the level of processing in sorghum silage. As BPS increased from 26.28 to 55.05 ± 0.04%, 7-h in situ starch digestibility increased from 50.54 to 82.07 ± 4.94% for unprocessed and heavily processed sorghum silage, respectively (R² = 0.43). By processing sorghum silage during harvest and measuring the extent of processing, sorghum silage starch digestibility can be enhanced and may serve as a viable alternative to corn silage in the diet of lactating dairy cows in areas of the country where corn silage is a high-risk forage crop due to lack of water. Study 3 evaluated the effects of 2 heat stress abatement systems on barn temperature, micro-environmental temperature, core body temperature (CBT), respiration rate, rear udder temperature, and lying time in lactating dairy cows. The systems evaluated were: direct cooling via feedline soakers and fans, or evaporative cooling via a fan and fog system. The evaporative cooling system was effective (P = 0.04) in reducing respiration rates (52.0 vs. 57.9 ± 2.2 breaths per min; P < 0.01) and rear udder temperatures (33.2 vs. 34.5 ± 0.3ºC; P < 0.01), and increased daily lying time (11.8 vs. 10.8 ± 0.3 h/d; P < 0.01) due to differences in barn THI and airflow. No treatment differences (P = 0.79) were detected for CBT, likely due to cooler ambient conditions during the study. Study 4 assessed the effects of the same evaporative and direct cooling systems as in Study 2 but were applied in the holding area prior to afternoon milking, where effects on CBT and micro-environmental temperature in lactating dairy cows were measured in addition to water usage by each system. No significant differences (P > 0.05) between direct cooling and evaporative cooling were detected for micro-environmental THI. However, the evaporative cooling system reduced the consumption of water in the holding area while maintaining CBT < 39.0ºC. Future research should be conducted under greater ambient THI to determine if an evaporative cooling system is able to maintain CBT < 39.0ºC, while also comparing CBT and water usage to a soaker system in the holding area.

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