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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.
81

Dinâmica do processo decisional e fluxo adaptativo de sistemas de produção leiteiros de base familiar

Bodenmüller Filho, Anselmo 11 1900 (has links)
Capes / O presente trabalho, de caráter exploratório e de abordagem sistêmica, procura colaborar a elaboração de critérios e técnicas de pesquisa sobre os sistemas de produção leiteiros (SPL). O objetivo principal é estudar como os SPL incorporam tecnologia. Para o desenvolvimento do trabalho, foram realizadas entrevistas em 60 propriedades com base em questionário, partindo-se da bacia leiteira da região sudoeste do Paraná. A base de dados permitiu demonstrar, no primeiro estudo, os perfis de dimensionamento a partir das áreas cultivadas com forrageiras e suas respectivas proporções e relações, somadas aos indicativos dos resultados produtivos. Os grupos retratam a dinâmica da gestão dos recursos forrageiros e marcam a diversidade de objetivos dos gestores, configurando cinco lógicas de dimensionamento da superfície forrageira para o atendimento da demanda. O segundo trabalho foi conduzido com o objetivo de avaliar os perfis decisionais com foco na dinâmica dos fluxos de informações, interações sociais, traços biográficos e de gestão administrativa, utilizando técnicas de análise multivariada. De acordo com uma abordagem apropriada para a tomada de decisão e aconselhamento técnico, evidenciou-se as práticas preferenciais de busca pela informação técnica, considerando os mecanismos de difusão de conhecimentos acionados para transferência de tecnologia. Foram identificadas variáveis importantes baseadas nos indicadores biográficos e de gestão que definem os fatores para modelagem em SPL. Objetivou-se com o terceiro trabalho verificar que o estudo das práticas nos postos de manejo colabora para explicitar a diversidade de SPL. E, ainda, permitir elencar implicações desta abordagem sobre o processo de tomada de decisão na agricultura familiar. Buscou-se delinear as estratégias gerais utilizadas nos SPL estudados pela interpretação dos eixos fatoriais com o uso da análise de correspondência múltipla (ACM). Foi evidenciado que na região estudada há diversidade de SPL com lógicas desigualmente alocadas para a construção dos resultados. Os resultados fornecem suporte para os trabalhos de difusão tecnológica a fim de promover aumento da taxa de adoção de novas práticas com impacto no desenvolvimento agrícola. / This work of exploratory nature and systemic approach, seeks to collaborate in the development of research criteria and techniques on dairy production systems (DPS). The main objective is to study how the DPS incorporate technology. For the development of the study, interviews based on a questionnaire were conducted in 60 properties, starting from the dairy region of the southwestern region of Paraná. In the first study, the database allowed showing the profiles of dimensioning from the areas planted with forage and their respective proportions and relations, together with indicative of productive results. The groups portray the dynamic of the management of forage resources and mark the diversity of managers’ objectives, setting five dimensioning logics of the forage area to meet the demand. The second study was conducted with the objective of evaluating the decision-making profiles focusing on the dynamics of information flows, social interactions, biographical features and administrative management using multivariate analysis techniques. According to an appropriate approach to decision making and technical advice the preferential practices of searching for technical information were highlighted, considering the mechanisms of knowledge dissemination triggered to transfer technology. Important variables were identified based on biographical and management indicators which define the factors for DPS modeling. The third study was carried out with the purpose of verifying that the study of practices in management positions contributes to explain the diversity of DPS. And it also allows to list the implications of this approach on the decision-making process in family farming. We tried to outline the general strategies used in the studied DPS by the interpretation of factorial axes using the multiple correspondence analysis (MCA). The study showed that there is DSP diversity in the region studied with unevenly allocated logics for the construction of the results. The results provide support for the studies on technology diffusion in order to promote increased rate of adoption of new practices with an impact on agricultural development.
82

Desempenho e comportamento de vacas leiteiras em pastagem de alfafa suplementada com silagem de milho e concentrado

Netto, Diego Peres [UNESP] 05 May 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-05-05Bitstream added on 2014-06-13T21:05:26Z : No. of bitstreams: 1 netto_dp_dr_botfmvz.pdf: 505159 bytes, checksum: fdbb2ee95004f51e21168fda4ef26f4b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Objetivou-se avaliar como a substituição parcial de silagem de milho por pastagem de alfafa afeta o desempenho de vacas leiteiras e a viabilidade econômica do sistema. Usaramse 24 vacas da raça Holandesa, em estádio médio de lactação, num delineamento em blocos ao acaso. O período experimental durou 84 dias. Os tratamentos foram: dieta à base de silagem de milho em confinamento; ou silagem de milho substituída parcialmente por pastejo restrito (limitado a quatro horas/dia) ou irrestrito de alfafa. O pastejo foi rotacionado, e a quantidade de concentrado igual (4,5 kg de MS/vaca/dia) em todos os tratamentos. A massa de forragem foi 2338,0 e 1878,0 kg de MS/ha e a oferta, 1,8 e 4,2 kg MS/100 kg PV, nos tratamentos pastejo restrito e irrestrito, respectivamente. A produção de leite não diferiu entre tratamentos, cujas médias foram 25,9±1; 25,8±1 e 25,2±1 litros/vaca/dia no confinamento, pastejo restrito e pastejo irrestrito, respectivamente. A produção de leite por área foi 59 litros/ha/dia no pastejo restrito e 63 litros/ha/dia no pastejo irrestrito, enquanto no confinamento foi 48 litros/ha/dia. A substituição parcial de silagem de milho por alfafa em pastejo não limitou o desempenho produtivo dos animais e mostrou-se economicamente vantajosa em relação ao confinamento. / The objective was to evaluate how the partial replacement of corn silage with alfafa grazing affects dairy cow performance and profitability. Twenty four Holstein dairy cows in mid-lactation were used in a randomized block design. The experimental period lasted 84 days. The treatments were: a corn silage-based diet fed on drylot; or partial replacement of corn silage with either restricted alfalfa grazing (limited to 4 hours/day) or unrestricted grazing. A rotational grazing system was used and the amount of concentrate fed was the same (4.5 kg of DM/cow/day) for all treatments. Forage availability was 2,338.0 and 1,878.0 kg DM/ha and forage-on-offer was 1.8 and 4.2 kg DM/100 kg LW under restricted or unrestricted grazing, respectively. No difference in milk production/cow/day was observed among treatments. Mean milk production was 25.9±1, 25.8±1 and 25.2±1 liters/cow/day for feedlot, restricted grazing or unrestricted grazing, respectively. Milk production per hectare was 59 liters/day under restricted grazing and 63 liters/day under unrestricted grazing, whereas it was 48 liters/day on drylot. The partial replacement of corn silage by alfalfa grazing did not limit animal performance and was shown to be economically advantageous as compared to drylot feeding.
83

Verificação dos efeitos das variâncias e das relações de variáveis ligadas à pecuária de leite no agrupamento dos produtores / Verification of the effects of variances and of the relationships among variables related to milk production in the grouping of dairy farmers

Campana, Ana Carolina Mota 16 February 2009 (has links)
Made available in DSpace on 2015-03-26T13:32:06Z (GMT). No. of bitstreams: 1 texto completo.pdf: 358534 bytes, checksum: 24e75168f2f6257c7ffe917ef5ade7c8 (MD5) Previous issue date: 2009-02-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Nowadays research often collect information on many variables from a great number of experimental units, hence produce and store large amount of data, which in turn requires methods that can handle such situations. Statistical methods such as the principal component analysis (PCA), that can reduce the dimensionality of the analysis without significant information loss, are of great interest. PCA can use either the covariance (S) or the correlation (R) matrix among variables, but the analysis may result in different Principal Components (PC) resulting from R or S. In order to indicate the best strategies for different scenarios, we conducted a simulation study to investigate the effects of variable scaling over the viability and quality of the results from PCA analysis used to cluster experimental units. In addition to this first simulation study, we also conducted a second one using animal science and economical variables from 255 dairy producers from three locations of Minas Gerais State. The goal was to verify the most appropriate data structure for cluster analysis, such that it best classifies the most economically viable producers. In both studies we used a transformation of variables based on its coefficient of variation, which resulted in a new covariance matrix named S*. Results showed that the use of matrix S favored economical variables with larger variances, while use of R matrix resulted as the most important variables the ones with larger correlations among them. Calculations of PC using matrix S* minimized these scaling problems when S and R matrices are used. Analysis using S is entirely affected by the variable scale while using R is not affected by the scale at all. We concluded that the S* matrix was the most appropriate for the present case study because it considered the most important economical variables to be the ones most related to the animal science variables. / Com o aumento substancial na quantidade de dados armazenados, surge a necessidade da utilização de métodos que permitam analisar simultaneamente várias variáveis medidas em cada elemento amostral, e ainda com a possibilidade de reduzir a dimensionalidade desse conjunto sem perda significativa de informação. Entre eles, pode-se citar o método dos componentes principais, cuja obtenção pode envolver a matriz de covariâncias (S) ou a de correlações (R) das variáveis de interesse. Como a utilização dessas matrizes pode fornecer diferentes componentes, objetivou-se investigar, por meio da simulação de dados, os efeitos das escalas das características sobre a qualidade e a viabilidade da classificação dos elementos amostrais, buscando assim, indicar estratégias de análise mais adequadas em diferentes casos. Além do estudo de simulação, foi realizado outro com variáveis zootécnicas e econômicas referentes a 255 produtores de leite de três regiões do estado de Minas Gerais, com o objetivo de verificar qual a melhor estrutura de dados em classificar de forma mais apropriada os produtores mais viáveis economicamente. Em ambos os estudos, foi efetuada uma transformação nos valores das variáveis baseada nos respectivos coeficientes de variação, cuja matriz de covariâncias foi denominada de S*. Observou-se que a utilização da matriz S privilegiou as variáveis econômicas de maiores variâncias, enquanto a matriz R considerou as variáveis mais correlacionadas entre si como as mais importantes. A obtenção dos CPs com base na matriz S* minimizou os problemas das escalas inerentes aos usos das matrizes S e R. A primeira, por considerá-la totalmente e, a segunda, por desconsiderá-la. Desta forma, considerou-se a matriz S* como a mais indicada no presente estudo de caso, uma vez que priorizou como mais importantes, as variáveis econômicas mais relacionadas às variáveis zootécnicas.
84

Vyhodnocení úrovně chovu skotu ve vybraném zemědělském podniku / The evaluation of cattle rearing in agricultural enterprise

JANEČKOVÁ, Jaroslava January 2011 (has links)
In this thesis breeding and economic indicators of stockbreeding in ?Agrodružstvo Žimutice? in the years 2005 ? 2009 have been assessed. The results show that the reared herd has a high breeding value. For the breeding high- quality approved bulls are used which are still increasing the above mentioned value. The rearing of calves and heifers is of high-quality too. The fattening of bulls lags behind. The increase in weight is very low. The rearing profitability was negative in all years. When compared to the data from a sample survey conducted by The Institute of Agricultural Economics and Information in Prague, it has been found that the company has high costs in particular as to the consumption of their own feeds, direct wages, internal services and overhead expenses. It is impossible to continue such uneconomic production. It is necessary to take a large number of measures to eliminate the loss.
85

Chovatelská analýza úrovně chovu skotu ve vybraném zemědělském podniku / The analyse of cattle breeding in an enterprise - case study

HORA, Ondřej January 2014 (has links)
This work deals with an analysis of breeding cattle in the agricultural cooperative Agra Březnice u Bechyně. Data on milk production and reproduction was obtained from records of performance tests and livestock records. The results of performance and reproduction in the years 2010 to 2012 shows that the monitored breeding achieved when compared to the average population of Czech Pied cattle bred in the Czech Republic, above-average values. The efficiency of milk production in the reporting period increased by an average of 394 kg. Milk composition is at the population level. The fat content was in the period, on average, 0.02% lower and the protein content was about 0.01% lower than the values of the population in the Czech Republic. The reproduction of purebred breeding is used in a closed herd turnover. The reproductive performance achieves significantly less value than the population average length of service period. The other reproductive indicators, with the exception of insemination index reached in the period better values than the average of these values achieved in the Czech Republic. The results showed that the most common reason for withdrawal from dairy herds are problems with disease of the legs and udder disease. These problems need to be addressed in the short term better approach to monitoring and prevention in the long term appears to be the most important completion of a new barn. The breeding value of bulls used in reproduction was satisfactory level.
86

Analýza vybraných vlivů na reprodukci dojnic u stáda holštýnského skotu / Analysis of selected effects on reproduction of dairy cows in the herd Holsteins

JEŘÁBKOVÁ, Vendulka January 2014 (has links)
This work shows that the level of reproduction is influenced primarily by management reproduction. Selected indicators reproductions reached cows of the Holstein breed below-average values u (service period, pregnancy after first insemination and insemination index) to average values (interim) and achieve the goals set out indicators breeding Holstein cattle in lactation. Recommendations for breeders is to improve search říjících the cows. Further improve the diagnosis of pregnancy in cows inseminated. Improve the overall management of the herd reproduction.
87

Vliv kvality a zpracování siláží a senáží na mléčnou užitkovost dojnic

VANĚK, Michal January 2016 (has links)
Thesis on quality impact and processing silage and silage on milk yield of dairy cows discusses the theoretical part, mainly on the composition of the diet and milk production. In addressing this issue is important to ensure animal welfare. An integral part of the milk production is respecting technological procedures harvesting and preservation of harvested crops. Silage quality and composition of the diet affect the proper function of the rumen, which has an impact on the quality and composition of milk. The quality of milk and its composition affects the purchase price of milk. The practical part deals with methodology and data processing of milk production, the composition of the ration and analysis of silage and their subsequent statistical processing. Further consideration was given to the possible influence of the season. Statistical results were then compared with many experts. The results fell the most in 2015, which increased the average monthly milk yield . In this year , the best fed silage and forage
88

Chovatelská a ekonomická analýza chovu skotu v zemědělském podniku

LHOTKA, Pavel January 2016 (has links)
The aim of the thesis is evaluation the breeding and economical factors of livestock breeding in agricultural company VOD Jetřichovec between 2012-2014 years. The data needed for economic analysis (balance sheet, income statement, cash flow) were are obtained from the accounting of the company. The data for analysis of reproduction (reproduction and milk production) were are compiled from records of performance tests and records of the animals. The statistical comparison with the average of the Czech Republic was carried out using the results of the tender Institute of Agricultural Economics and Information. The results of performance and reproduction in the years 2012 to 2014 shows that the monitored breeding achieved when compared to the average population of Holstein cattle bred in the Czech Republic, above-average values. The statistical comparison with the average of the Czech Republic was carried out using the results of the tender Institute of Agricultural Economics and Information. Excellent research results gained in VOD Jetřichovec arises. The reproduction of purebred breeding is used in a closed herd turnover. The reproduction of purebred breeding is used in a closed herd turnover. The main value of the reproductive indicators, performance and breeding bulls in a company are comparable or better than the national average. In milk production, which is the main indicator of dairy cows, the amount of milk produced and sold on average 13% higher. The rearing of calves and heifers is also at a high level, as evidenced by the low mortality and good health. Fattening bulls has a very high level, which is monitored each year, compared profitable UZEI research. To improve economic and breeding levels would be necessary in the long term to increase production, reduce costs, focus on improving livestock breeding through a professional approach and application of innovative technologies.
89

Chovatelská a ekonomická analýza chovu dojeného skotu ve vybraném zemědělském podniku

BUŘIČOVÁ, Hana January 2018 (has links)
The aim of this work was to analyze breeding and economical indicators of cattle breed in Selekta Pacov ltd. and on a private farm of Mr. Lubomir Straka in years 2014-2015. The results show, that in both cases, these plants are very modern and continuously innovated with high standard of milk performance, good health state of all milk cows, high-quality nutrition and appropriate farm management. Reproduction indicators are acceptable in both cases and correspond with the high milk performance. Economic result corresponds with the excellent level of milk cows breeding; both companies show profit during whole period of observation. Calf breeding is at high level on both farms as well. The farm of Mr. Straka shows the only problem; due to shortage of workforce, the farm has relatively high calf loss. In the heifer category, the results in breeding economy and breeding indicators are at high level. These animals are fully grown and developed with great body proportions and optimal body condition; this is the precondition of high milk performance. Bull fattening is realized in Selekta ltd. only; Mr. Lubomir Straka doesn´t fatten the bulls, but he sells them as calves already. For Selekta ltd., this commodity is an unprofitable branch. The reasons are low growth during fattening and high feed costs. If these problems are not removed, it will be better to cancel this category.
90

As Transformações na cadeia produtiva do leite : o caso do distrito São Bento, Carazinho, RS

Bairros, Adriano de January 2009 (has links)
A partir da década de 1990 ocorreram, em todo o território brasileiro, crescimentos na produção e produtividade leiteiras. Esse fato é conseqüência das transformações ocorridas na cadeia leiteira, a partir desse período, as quais se sucederam com o fim do tabelamento do leite no ano de 1991, abertura comercial e consolidação do MERCOSUL. Uma das conseqüências diretas dessas transformações foi a crescente instalação de indústrias de laticínios multinacionais, em território nacional, dentre elas a Parmalat. Nesse sentido, o município de Carazinho, RS também apresentou crescimentos na produção e produtividade leiteiras. Como a Parmalat se instalou nesse município na década de 1990, a presente pesquisa procurou verificar o grau de influência tecnológica dessa empresa junto aos produtores de leite do local. Para tanto, escolheu-se, como amostra da pesquisa, um distrito de Carazinho denominado Distrito de São Bento. Dessa forma, verificou-se que essa empresa trouxe impactos para o contexto da produção leiteira no município, mas que o principal impacto está relacionado às exigências de qualidade do leite através da Instrução Normativa 51 (IN 51), lei esta promulgada, em todo o país, no ano de 2002. / From the 1990's occurred throughout the Brazilian territory, increases in milk production and productivity. This is a consequence of changes in the dairy chain, from that period, which is done with the end of the table of the milk in the year 1991, trade liberalization and consolidation of MERCOSUR. One of the direct consequences of these changes was the increasing installation of the dairy multinational industries in the national territory, including the Parmalat. Accordingly, the municipality Carazinho, RS also showed increases in milk production and productivity. As Parmalat is installed in that city in the 1990s, this research sought to verify the degree of influence that technology with the company's local milk producers. For both, chose, as the research sample, a district of Carazinho called District of St. Benedict. Thus, it was found that this company has impacts in the context of milk production in the municipality, but the main impact is related to demands for quality of milk through the Normative Instruction 51 (IN 51), enacted this law in any country, in 2002.

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