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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.
41

Turnover de carbono e a preferência alimentar de ovelhas por isótopos estáveis

Martins, Marcela Buosi [UNESP] 23 June 2010 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-06-23Bitstream added on 2014-06-13T20:56:38Z : No. of bitstreams: 1 martins_mb_me_botfmvz.pdf: 732603 bytes, checksum: aaa29421580edf9cbe7e5d86e1091b6f (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / Este trabalho objetivou avaliar o turnover e a meia-vida do carbono nas fezes e sangue de ovelhas alimentadas com plantas C3 e C4, pela técnica dos isótopos estáveis. Oito ovelhas da raça Santa Inês, após um período de adaptação de 45 dias recebendo 50% de feno de alfafa e 50% de silagem de milho, foram distribuídas ao acaso em dois tratamentos: o primeiro consistiu de animais que receberam feno de alfafa (C3-FA) e o segundo, dos animais que receberam apenas silagem de milho (C4-SM). Para mensurar o turnover de carbono (substituição isotópica) nas fezes e sangue em determinado intervalo de tempo, foi utilizada a função exponencial do tempo. Apenas os valores isotópicos das fezes atingiram o patamar de equilíbrio, indicando valores de meia-vida de 1,2 e 1,0 dias para os tratamentos C3-FA e C4-SM, respectivamente. Já no sangue, o tempo de coleta dos dados (104 dias) foi insuficiente para encontrar o patamar de equilíbrio isotópico, indicando uma troca de carbono lenta. De acordo com os resultados deste estudo, pode-se concluir que o sangue apresenta turnover lento indicando o sinal isotópico de dietas antigas; e as fezes, turnover rápido, indicadas para refletir dietas recentes, próximas da fase de avaliação / The aim of this work was to evaluate the carbon turnover and half-life on feces and blood sheep, fed on C3 and C4 plants, using the stable isotopes technique. Eight Santa Ines sheep, after 45 days as adjustment period receiving 50% of alfalfa hay and 50% of corn silage, were randomly assigned to two treatments: the first one the animals fed on alfalfa hay (C3-FA) and the second one the animals fed on only corn silage (C4-SM). The time exponential function was used to measure the carbon turnover (isotope substitution) on feces and blood in a certain period of time. Only the isotope feces values reached the plateau value, indicating half-life of 1.2 and 1.0 days for C3-FA and C4-SM treatment, respectively. The data collection time (104 days) for blood was not enough to find a plateau isotope, indicating a slow carbon exchange. So we can infer that the blood has a slow turnover, indicating isotopic signal of ancient diets; and the feces showed a fast turnover, being used to reflect recent diet, next to the evaluation period
42

Silagem de milheto e de milho na dieta de vacas leiteiras /

Rêgo, Aníbal Coutinho do. January 2012 (has links)
Orientador: Mauro Dal Secco de Oliveira / Banca: Jane Maria Bertocco Ezequiel / Banca: Ana Claudia Ruggieri / Banca: Flávia Fernanda Simili / Banca: André de Faria Pedroso / Resumo: Objetivo-se avaliar o efeito do tamanho de partícula, 5 ou 20 mm e o uso ou não de Lactobacillus plantarum associado a Propionibacterium acidipropionici na silagem de milheto comparada a silagem de milho em três experimentos. No primeiro avaliou-se a temperatura das silagens, o gradiente de temperatura entre silagem e ambiente, e valores de pH antes e após o descarregamento da silagem em diferentes regiões de cinco silos de superfície. A temperatura antes e após a retirada da fatia de silagem, assim como o gradiente de temperatura entre silagem e ambiente em silos de milheto e milho é menor no estrato inferior do perfil. Silagens de milheto apresentam menores valores de pH no estrato inferior do silo, 5,1 e 4,3 antes e após o descarregamento, respectivamente. No segundo e terceiro experimentos, foram avaliadas dietas contendo silagem de milheto com partículas de 5 ou 20 mm e contendo ou não inoculante comparada a silagem de milho, sobre o consumo e a digestibilidade das dietas, produção e composição do leite, e comportamento ingestivo dos animais. Vacas alimentadas com dietas contendo silagem de milho produzem mais leite (17,4 kg/dia) corrigido para 3,5% de gordura do que vacas alimentadas com dietas contendo silagem de milheto (15,0 kg/dia), em maiores consumos de MS (16,9 kg/dia) e NDT (10,9 kg/dia). Silagem de milheto com 20 mm de tamanho de partículas proporciona boa eficiência produtiva comparada a silagem com 5 mm. O uso do inoculante na silagem de milheto não altera o consumo e a digestibilidade das dietas. Silagem de milho ou milheto, tamanho de partículas, e o uso do inoculante, não altera o tempo total despendido com alimentação, ruminação e ócio dos animais / Abstract: The purpose of the present study was to study the effects of 5 or 20 mm particle size, and the use or non use of Lactobacillus plantarum associated with Propionibacterium acidipropionici in millet silage compared to corn silage. In the first experiment were conducted to evaluate the temperature of the silage, the temperature gradient between silage and environment, and pH values before and after removal of slices of silage in different regions of five surfaces silos. The temperature before and after removal of the slice of silage, as well as the temperature gradient between the environment and the silage, in surface silos of millet and corn silage, is lower in the lower strata of the profile. Millet silage has lower pH values in the lower strata of the silo, 5,1 and 4,3 before and after unloading, respectively. The second and third experiments, diets containing millet with particle size of 5 or 20 mm, with or without inoculant, compared to corn silage on intake and digestibility of diets, the production and milk composition, and feeding behavior of animals were evaluates. Cows fed diets containing corn silage produced more milk (17.4 kg/day) corrected for 3.5% fat than cows fed diets containing millet silage (15.0 kg/day), higher intakes of DM (16,9 kg/day) and TDN (10.9 kg/day). Silage with 20 mm particle size, in the diet of dairy cows, leads to greater production efficiency. The use of inoculants in millet silage affects neither the consumption and digestibility of diets. Millet and corn silage, particle size, inoculants, does not alter the time spent on eating, ruminating and restring animals / Doutor
43

Demanda energética na colheita, degradabilidade e digestibilidade da silagem de híbridos de milho /

Factori, Marco Aurélio, 1980- January 2011 (has links)
Orientador: Ciniro Costa / Banca: Heraldo César Gonçalves / Banca: Mario De Beni Arrigoni / Banca: Paulo Roberto Arbex Silva / Banca : Wagner dos Reis / Resumo: O milho é a cultura mais utilizada para confecção de silagem nos sistemas de produção de ruminantes. Para tanto, são encontrados no mercado, cultivares que se diferem em características morfofisiológicas. A eficiência do processo não deve ser avaliada somente pelo valor nutritivo do produto final, mas também pelos custos por kg de massa seca colhida. O objetivo deste trabalho foi avaliar o consumo de energia na colheita de híbridos de milho para ensilagem em função da textura do híbrido (dentada e dura), quatro maturidades de colheita (1/2 leitoso, 1/4 leitoso, início de maturação fisiológica e maturação fisiológica) e três tamanhos de partículas - Tp (2, 7 e 11mm). Foi utilizado no experimento um trator da marca Massey Ferguson, modelo MF 610 de 86 cv. Para colheita e corte da forragem, utilizou-se colhedora de forragem, marca JF Máquinas, modelo JF92 Z10. Para obtenção dos dados de consumo de combustível (Cc) e tempo gasto para cada parcela utilizou-se um fluxômetro, instalado próximo ao filtro de combustível do trator. O delineamento experimental utilizado foi o inteiramente casualizado em esquema de parcelas subdivididas. Para os parâmetros avaliados, foi verificada interação tripla entre os fatores hibrido*estádio de colheita*Tp. A velocidade e deslocamento do trator foram diferentes para as maturidades somente para o híbrido de textura dura. O Cc por hora para o híbrido dentado aumentou em maturidades mais precoces de colheita e em menores Tp. O consumo por kg de massa seca produzida foi menor em maturidades mais tardias, textura dentada e dura respectivamente em função da maior produção de massa. A potência teórica foi maior em maturidades mais precoces (textura dentada e dura respectivamente) e para o fator rendimento, foram observados maiores... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Corn is the crop most used for making silage in ruminant production systems. For both, are found in the market, cultivars that differ in morpho-physiological characteristics. The efficiency of the process should not be assessed only by the nutritional value of the final product, but also by cost per kg of dry matter harvested. The objective of this study was to evaluate energy consumption in the harvest of corn hybrids for silage due to the texture of the hybrid (and bite hard) and four harvest maturities (1 / 2 milky, 1 / 4 milky beginning of physiological maturity and physiological maturity) and three sizes of particles - Tp (2, 7 and 11mm). Was used in the experiment of a Massey Ferguson tractor, model 610 MF 86 hp. Harvesting and cutting the grass, we used forage harvester, JF Machines brand, model Z10 JF92. To obtain data on fuel consumption (CC) and time spent for each plot, we used a flow meter, installed near the fuel filter of the tractor. The experimental design was completely randomized in a split-plot. All the variables, there was triple interaction between factors harvesting stage hybrid * maturity stages * Tp. The velocity and displacement of the tractor for the different maturities were only for the hybrid hard texture. Cc per hour for the hybrid toothed increased harvest maturity earlier and at lower Tp. Consumption per kg of dry matter produced was lower in later maturities, texture and bite hard respectively due to the greater mass production. The theoretical power was higher in the earliest maturity (hard bite and texture, respectively) and factor income, higher yields were observed for hybrid hard texture in the most advanced. It can be concluded that fuel consumption was lower in late crop maturity and the hybrid hard... (Complete abstract click electronic access below) / Doutor
44

Effect of BT maize on earthworm activity, silage quality and residue decomposition in the central Eastern Cape

Kamota, Agathar January 2011 (has links)
There are concerns that genetic modification of maize with Bacillus thuringiensis may influence its structural and chemical composition which, together with the Cry1Ab proteins, may affect agro-ecosystem processes and feed quality. This study was aimed at investigating the expression of Cry1Ab protein in leaves, stems and roots of Bt maize and the effect of genetic modification (MON810) on activity of earthworms, silage quality and decomposition of residues in the field. In 2009/10 four maize cultivars; DKC61-25B, DKC61-24, PAN6Q-321B and PAN6777 were planted. Expression of Cry1Ab in leaves, stems and roots was analyzed at 6, 8, 10 and 12 weeks after planting (WAP). Earthworms were also sampled from the same treatments at 6, 9 and 18 WAP. Two silage experiments were conducted using maize cultivars, DKC80-12B and DKC80-10 produced in the 2008/09 season and DKC61-25B, DKC61-24, PAN6Q-321B and PAN6777, produced in 2009/10. The silage was sampled at 0, 2, 4, 8, 15 and 42 days in 2008/09 and 0, 8 and 42 days in 2009/10 and analyzed for Ash Free Dry Matter, Crude Fiber, Neutral Detergent Fiber, Acid Detergent Fiber, Acid Detergent Lignin, Crude Protein and Total Digestible Nutrients. Two litter-bag decomposition studies were also carried out (i) in 2008 (surface applied) using maize cultivars DKC80-12B, DKC80-10 and DKC6-125 residues and (ii) in 2009 (soil incorporated) using DKC75-15B, CRN3505, PAN6Q-321B v and PAN6Q-121. Ash-free dry matter and Cry1Ab protein were measured throughout the incubation time. There were no differences between DKC61-25B and PAN6Q-321B in terms of expression of Cry1Ab in leaves, stems and roots over time. The Cry1Ab expression levels were in decreasing order: leaves > stems > roots. No effects of Bt maize on earthworm numbers and biomass were observed. There were no differences in all silages parameters except NDF and ADF, which were higher in the Bt maize silage than that of the non-Bt maize from the 2008/09 season. The Cry1Ab levels were essentially not reduced during ensiling. The maize residues (both Bt and non-Bt maize) degraded to similar levels, either when surface-applied or incorporated into soil but soil-incorporated residues decomposed faster than surface-applied ones. Cry1Ab degraded as the plant matrix decomposed. The findings suggested that maize genetically modified with the Bt MON810 event can be grown in the Central Eastern Cape without affecting earthworm numbers and biomass, silage quality and decomposition of maize residues.
45

Effects of Corn Silage Hybrids and Dietary Nonforage Fiber Sources on Productive Performance in Early Lactating Dairy Cows Fed High Forage Diets

Holt, Michael Shane 01 May 2010 (has links)
This experiment was conducted to determine the effects of corn silage hybrids and nonforage fiber sources (NFFS) in high forage diets formulated with high dietary proportion of alfalfa hay (AH) and corn silage (CS) on ruminal fermentation and productive performance by early lactating dairy cows. Eight multiparous Holstein cows (4 ruminally fistulated) averaging 36 ± 6.2 d in milk were used in a duplicated 4 × 4 Latin square design experiment with a 2 × 2 factorial arrangement of treatments. Cows were fed 1 of 4 dietary treatments during each of the four 21-d periods. Treatments were: 1) conventional corn silage (CCS)-based diet without NFFS, 2) CCS-based diet with NFFS, 3) brown midrib corn silage (BMRCS)-based diet without NFFS, and 4) BMRCS-based diet with NFFS. Diets were isonitrogenous and isocaloric. Sources of NFFS consisted of ground soyhulls and pelleted beet pulp to replace a portion of AH and CS in the diets. In vitro 30-h NDF degradability was greater for BRMCS than CCS (42.3 vs. 31.2%). Neither CS hybrids nor NFFS affected intake of DM and nutrients. Digestibility of N, NDF, and ADF tended to be greater for cows consuming CCS-based diets. Milk yield was not influenced by CS hybrids and NFFS. However, a tendency for an interaction between CS hybrids and NFFS occurred with increasing milk yield due to feeding NFFS with the BMRCS-based diets. Yields of milk fat and 3.5% FCM decreased when feeding the BMRCS-based diet, and there was a tendency for an interaction between CS hybrids and NFFS by further decreased milk fat concentration because of feeding NFFS with BMRCS-based diet. Although feed efficiency (milk/DM intake) was not affected by corn silage hybrids and NFFS, there was an interaction between CS hybrids and NFFS because feed efficiency increased when NFFS was fed only with BMRCS-based diet. Total VFA production and individual molar proportion were not affected by diets. Dietary treatments did not influence ruminal pH profiles except that duration (h/d) of pH < 5.8 decreased when NFFS was fed in CCS-based diet but not in a BMRCS-based diet, causing a tendency for an interaction between CS hybrids and NFFS. Overall measurements in our study reveal that high forage NDF concentration (20% DM on average) may eliminate potentially positive effects of BMRCS. In the high forage diets, NFFS exerted limited effects on productive performance when they replaced AH and CS. Although the high quality AH provided adequate NDF (38.3% DM) for optimal rumen fermentative function, the low NDF concentration of the AH and the overall forage particle size reduced physically effective fiber and milk fat concentration.
46

Effects of potassium, magnesium, and sulfur fertilization on corn grain and silage yields in a high nutrient soil

Badra, Abdo January 1990 (has links)
No description available.
47

The Effects of European corn borer on whole-plant yieldand root knot nematode fitness in corn

Tiwari, Siddharth 07 May 2007 (has links)
Field studies were conducted over two growing seasons to evaluate the effect of different levels of third instar European corn borer, Ostrinia nubilalis Hübner (Lepidoptera: Crambidae), on whole-plant dry matter in corn grown for silage. Mean (± SEM) whole-plant dry matter was significantly greater by 18.8% in uninfested control plants than in plants with an infestation level of 6 larvae/plant in 2004. Whole-plant dry matter in 2005 was significantly greater by 10.5% in control plants than in plants with an infestation level of 5 larvae/plant. Economic injury levels were calculated for each year using regression equations between whole-plant dry matter and European corn borer infestation level. Plant growth stage and infestation level had no effect on percent acid detergent fiber, neutral detergent fiber, and crude protein values for either year. Greenhouse studies were conducted to examine the relationship between aboveground herbivory by European corn borer and belowground herbivory by root knot nematode, Meloidogyne incognita Chitwood (Tylenchida: Heteroderidae), in corn. Two experiments were conducted to measure belowground herbivory by M. incognita in juvenile penetrations and eggs/root system. In the first experiment, the main effects interaction was not significant for either M. incognita juvenile penetrations or eggs/root system. Overall mean juvenile penetrations/root system across all three growth stages, at infestation levels of 1 and 3 larvae/plant were significantly less than in the non-infested control. In addition, overall mean eggs/root system at an infestation level of 3 larvae/plant were significantly less than in the control. In the second experiment, the main effects interaction was significant for both juvenile penetrations and eggs/root system. At the 8 and 10 leaf growth stages, juvenile penetrations/root system at infestation levels of 1 and 3 larvae/plant were significantly less than in the control. In addition, eggs/root system at an infestation level of 3 larvae/plant were significantly less than in the control, at all growth stages. In the reciprocal study, which examined the effect of different M. incognita inoculation levels on European corn borer stalk tunneling, no significant effect of inoculation level on European corn borer stalk tunneling was found. / Ph. D.
48

Japanese Honeydrip Sorghum Silage versus June Corn Silage for Milk Production

Cunningham, W. S., Reed, J. R. 01 August 1927 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
49

Hodnocení kvality konzervované objemné píce při různých způsobech konzervace a skladování. / The evaluation of quality of conserved bulky fodder by different way of conservation and storage

KODADOVÁ, Lenka January 2017 (has links)
The thesis in the first part deals with the characteristics of major equipment as a source of coarse fodder for preservation. Given the difficult preservability is more prominent characteristic of legumes and their importance in the cultivation of coarse fodder. It describes the significance of clover-grass mixtures in the production of coarse fodder. Methods of harvesting and conservation of grassland biomass. It is also described silage corn, the preservability, harvest methods and importance in animal nutrition. Quality coarse fodder and the factors affecting it. Influence the quality of the biomass input on preservation processes. Furthermore, also deals with the procedures and principles of the production of silage, hay and silage, preservatives and finally summarizes the deterioration of the quality of silage and forage and impact deteriorated for receiving fodder and animal performance.The second part is focused on the monitoring of sensory properties and quality assessment laboratory conserved forage preservation in different ways - loose hay, hay bales, silage pits in silage, clover silage bales and silage in silage pits on lands selected agricultural cooperative. In conclusion, the most important measures designed to improve the quality of canned food.
50

Protocolos de adaptação à dietas com alta inclusão de concentrados para bovinos nelore confinados

Parra, Fernando Salvador [UNESP] 27 May 2011 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:28Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-05-27Bitstream added on 2014-06-13T20:16:54Z : No. of bitstreams: 1 parra_fs_me_botfmvz.pdf: 721193 bytes, checksum: bd20823954150f08063b8abd997438d6 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / O objetivo deste estudo foi avaliar os efeitos de protocolos de adaptação à dietas com alta inclusão de concentrados sobre o desempenho, seletividade dos ingredientes da dieta e características de carcaça de bovinos Nelore terminados em confinamento. Cento e vinte bovinos, machos não castrados com peso médio inicial (PI) de 372,19 ± 21,46 kg, provenientes de sistema de recria em pasto, foram mantidos por 84 dias em 24 baias de piso de concreto (5 animais/baia), de acordo com os tratamentos: protocolo de escadas por 14 dias (S14), protocolo de escadas por 21 dias (S21), protocolo de restrição por 14 dias (R14) e protocolo de restrição por 21 dias (R21), constituindo-se assim delineamento experimental em blocos casualizados, em arranjo fatorial 2 × 2 (protocolo escada ou restrição e duração de 14 ou 21 dias), com 6 repetições/tratamento, distribuídas em 6 blocos. Nenhuma diferença foi encontrada (P>0,10) para PI, peso final, ganho de peso diário, ingestão de matéria seca em quilos, conversão alimentar e eficiência alimentar com relação ao efeito de protocolos de adaptação. Houve interação (P<0,05) entre protocolo e duração, onde S21 proporcionou maior ingestão de matéria seca em porcentagem do peso vivo em relação a R21 (2,43 vs. 2,34). Nos 2 primeiros dias do período de terminação, os animais submetidos aos protocolos com duração de 14 dias selecionaram a favor de partículas maiores. O protocolo de restrição proporcionou maior (P=0,10) espessura de gordura subcutânea em comparação ao protocolo de escadas. Não houve diferença (P>0,10) para gordura visceral em quilos, gordura visceral em porcentagem da carcaça quente e custo por quilo de peso vivo. O peso de carcaça quente e o rendimento de carcaça foram maiores (P<0,05) para a duração de 14 dias, comparado à duração de 21 dias (285,61 vs. 278,72 e 56,76 vs. 56,13). A adaptação... / This study, conducted at the São Paulo State University feedlot, Botucatu Campus, Brazil, was designed to determine effects of restricting intake of the final finishing diet (REST) as a means of dietary adaptation compared to diets increasing in concentrate (STEPUP) over periods of 14-d or 21-d on overall feedlot performance, selectivity of the dietary ingredients and carcass characteristics. The experiment was designed as a completely randomized block with a 2 x 2 factorial arrangement, replicated 6 times (5 bullocks/pen), in which 120 18-mo-old yearling Nellore bulls (372.2 ± 21.5 kg) were fed in 24 pens for 84-d according to the treatments: STEPUP for 14-d, STEPUP for 21-d, REST for 14-d, and REST for 21-d. The STEPUP program consisted of ad libitum feeding of three adaptation diets over periods of 14-d or 21-d with concentrate level increasing from 55% to 85% of diet DM. The REST program consisted of restricted intake of the final diet (85% concentrate) with programmed increases in feed offered until yearling bulls reached ad libitum access over periods of 14-d or 21-d. No significant (P > 0.10) protocols and days main effects were observed for any of the feedlot performance parameters analyzed: initial and final BW, ADG in kg, F:G ratio, G:F ratio and DMI in kg, however a interaction was found (P < 0.05) for DMI in % of BW. Animals in STEPUP for 21-d treatment presented greater DMI (% of BW) than yearling bulls in REST for 21-d (2.43% vs. 2.34%). Animals in REST treatment had greater (P=0.10) 12th rib fat thickness than the STEPUP. With respect to carcass characteristics, no significant (P > 0.10) protocols and days main effects were observed for kidney-pelvic fat, kidney-pelvic fat in HCW percentage and cost of gain, however, yearling bulls in treatments that lasted 14-d presented heavier (P < 0.05) HCW (285.61 kg vs. 278.72 kg) and increased (P < 0.05) dressing percentage... (Complete abstract click electronic access below)

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