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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

'n Kritiese evaluering na die effektiwiteit van bestuurstrategieë vir ekstensiewe wolskaapboerdery in die groter Burgersdorp omgewing

Coetzee, Johanna Magdalena January 2002 (has links)
The main objectives of this study can be divided into three categories. In the first place it refers to the determination of production- and reproduction norms for the different main production areas in the greater Burgersdorp area, to promote production. In the second place it refers to the determination of the different management styles of sheep farmers in the greater Burgersdorp area. In the third place it refers to the calculation of gross margins for sheep farming in the greater Burgersdorp area, to establish the sustainable economic position. The survey area (the greater Burgersdorp area) includes the magisterial districts of Burgersdorp, Molteno, Steynsburg and Venterstad. The four magisterial districts were divided into two main production areas namely Stormberg Highveld and Burgersdorp Lowveld. Stormberg Highveld includes Molteno and the high-lying area (highveld) of Burgersdorp. Burgersdorp Lowveld comprises Steynsburg, Venterstad and the low-lying area (lowveld) of Burgersdorp. The management strategies of sheep farmers in the survey area were determined by means of a questionnaire and statistically analysed. The economic analyses of the sheep industry (wool and meat) were performed with the Geyer computer model. In this study it showed that the Dorper farmers obtained the highest gross margin per sheep. The lowest gross margin per sheep resulted from the Vleismerino farmers. Although the composition of the gross production value and the directly allocatable variable costs compare favourably, each main production area has unique management strategies for the different sheep breeds. The different management strategies can serve as the norm for extensive sheep farming, applicable to the specific main production area.
12

Evaluation of Physical and Behavioral Traits of Llamas (Lama glama) Associated with Aggressiveness Toward Sheep-Threatening Canids

Cavalcanti, Sandra M. C. 01 May 1997 (has links)
Canid predation poses a serious threat to the sheep industry in the United States. Llamas are becoming popular among livestock producers as part of their predation management programs but there is little information on the factors associated with llama guarding behavior. This study examined several physical and behavioral attributes of individual llamas to assess whether they might predict the aggressiveness llamas display coward canids. The study was conducted in three phases. The first involved determining some physical and behavioral traits of individual llamas. Twenty individuals were randomly assigned to one of four groups (n = 5/group) and frequencies with which animals initiated and responded to various behaviors, e.g., dominance, aggression, threats, subordination, leadership, and alertness, were documented using focal-group sampling. Individuals were then ranked according to the frequency with which they displayed each behavior. In the second phase, activity patterns of individual llamas with sheep were assessed. Lamas varied in how close to sheep they stayed (mean = 48.2 m I 3.5) as we 1 as in the way they distributed their activities. The third phase examined interactions among llamas, sheep, and a domestic sheep dog to assess their individual aggressiveness toward canids. Llamas varied in the degree of aggressiveness displayed toward the dog; some chased the dog, others ran from it, some stayed with the flock, and others did not. Llamas were ranked based on these responses. Llamas with top ranks were curious and chased the dog, but stayed close to the sheep. Bottom-ranked individuals ignored the sheep and ran from the dog. Physical and behavioral traits of llamas and their behavioral patterns with sheep were then compared with aggressiveness they displayed toward the dog. Leadership and alert behaviors were correlated with aggressiveness (r = 0.472, p = 0.064 and r = 0.607, p = 0.012, respectively) Weight of llamas was also correlated with aggressiveness (r = 0.475, p = 0.039). Llama coloration was associated with aggressiveness they displayed toward the dog (X2 = 6.003, df = 2, p = 0.049), however, color was also associated with the weight of llamas (X2 = 7.49, df = 2, p = 0.024). Traits correlated with llama aggressiveness are easily recognized and sheep producers interested in acquiring a llama should consider them when selecting livestock guardians.
13

'n Studie van dorperskaapboerdery in die dorperlandgebied

Ackermann, Jacobus Johannes 12 1900 (has links)
Thesis (MScAgric) -- Stellenbosch University, 1993. / ENGLISH ABSTRACT: A model of interdependents that makes provision for the particular needs of dorper sheep farming and is based on the relationship between the main groups of behaviour determined variables, was constructed. This model served as a basis for an interview schedule whereby personal interviews were held with 130 randomly drawn dorper farmers in the summer rainfall area of the Dorperland. Various independent and mediatory variables were examined and in certain cases it was quantified. Thus certain relationships between the needs, aspirations and endeavours of the respondents and their particular personal and environmental factors were determined. The determination of the independent and mediatory variables provide the extension officer with important background information whereby the application/non-application of certain practices as well as the efficiency of practice application are put into perspective. In this respect the findings of this survey serve as an important reference point by which specified extension actions could be evaluated in the future. The effectiveness of practice application is determined on the basis of 5- and 10-point scales as well as a description of what is actually done. In doing this the existence of certain definite differences between the perceptions of the respondent~ concerning the efficiency of praxis application and the assessment of the interviewers, baled on • description of what is actually done, was found. Practice accepta1Ce, • manifested in efficiency is measured on the basis of particular effectivity stMcWds. Thus relationships between the efficiency standards and certain personal, socioeconomical, socia-psychological and biological-technical variables wet"d determined. / AFRIKAANSE OPSOMMING: 'n Model van interafhanklikes wat voorsiening maak vir die eiesoortige behoeftes van dorperskaapboerdery en gebaseer is op die verwantskap tussen die hoofgroepe van gedragsbepalende veranderlikes, is gekonstrueer. Hierdie model het as basis gedien vir 'n onderhoudskedule aan die hand waarvan persoonlike onderhoude met 130 ewekansig gelote dorperboere in die somerreenvalgebied van Dorperland gevoer is. Verskeie onafhanklike en bemiddelende veranderlikes is ondersoek en in sekere gevalle is dit gekwantifiseer. Sodoende is verwantskappe tussen die behoeftes, aspirasies en strewes van die respondente en bepaaIde persoonlike- en omgewingsfaktore van sodanige respondente bepaal. Die bepaling van die onafhanklike- en bemiddelende veranderlikes bied die voorligter belangrike agtergrondinligting op grond waarvan die toepassing/nie-toepassing van bepaalde praktyke asook die doeltreffendheid van praktyktoepassing in perspektief geplaas word. Die mate waartoe sekere praktyke wat met dorperskaapboerdery verband hou toegepas word. is ook bepaal. In hierdie verband dien die bevindinge van hierdie ondersoek as belangrike verwysingspunte aan die hand waarvan bepaalde voorIigtingsaksies in die toekoms geevalueer kan word. Die doeltreffendheid van praktyktoepassing is aan die hand van 5- en 10puntskale. asook 'n omskrywing van wat werklik gedoen word, bepaaI. Sodoende is die bestaan van sekere duidelike verskille tussen die persepsies van die respondente wat betref die doeltreffendheid van praktyktoepassing en die aansIag van opnemers, gebaseer op 'n beskrywing van wat werklik gedoen word, bevind. Praktykaanvaarding, saos dit manifesteer in doeltreffendheid. is aan die hand van bepaalde doeltreffendheidsmaatstawwe gemeet. Sodoende is verwantskappe tussen die doeltreffendheidsmaatstawwe en sekere persoonlike, sosio-ekonomiese, sosio-psigologiese en biologies-tegniese bepaal.
14

Sistema agroindustrial do leite de ovelha no Brasil: proposta metodológica para estudo de cadeias curtas / Dairy sheep's agribusiness system in Brazil: methodological approach to the study of short food supply chains

Santos, Fernanda Ferreira dos 03 June 2016 (has links)
A ovinocultura leiteira tornou-se importante economicamente na América do Sul nas últimas décadas, sendo ainda pouco estudada no Brasil. O leite é destinado à produção de queijo, proporcionando valor agregado, sendo considerado fonte de renda aos produtores. Como ponto de partida para o estudo da ovinocultura leiteira, é proposta a descrição do sistema agroindustrial (SAG) para a melhor compreensão das relações entre os agentes. O estudo das cadeias agroalimentares, visando desempenho econômico superior, utiliza abordagens da microeconomia como Economia dos Custos de Transação (ECT), Economia dos Custos de Mensuração (ECM), Visão Baseada em Recursos (VBR) e Teoria do Empreendedor. Dentro dos SAGs existem as cadeias agroalimentares curtas, formas de organização e comercialização que buscam a proximidade entre produtores e consumidores. Este trabalho teve como objetivo descrever o SAG do leite ovino no Brasil, buscando entender as estratégias adotadas pelos agentes e propor uma metodologia de estudo as cadeias curtas. A pesquisa foi do tipo exploratória e de multi-caso, por meio de entrevistas com questionários pré-formulados. O SAG do leite ovino foi caracterizado como um sistema em cadeia curta pela aproximação do produtor com o consumidor, possuindo, na maior parte das vezes, apenas um agente responsável pelas diferentes etapas da cadeia. O sistema é composto, em termos de transformação tecnológica, em quatro grandes elos: insumos, produção primária, agroindústria e distribuição, sendo os insumos adquiridos em mercados spot. Foram identificadas 18 fazendas produtoras no país. As raças predominantes eram Lacaune e East Friesian, com média de 1,17 litros de leite/animal/dia, abaixo da média potencial para as raças (2 litros). Observou-se que 14 entre as 18 propriedades apresentam mão de obra familiar. Dentre os laticínios, quatro possuíam inspeção federal, três possuíam inspeção estadual e três possuíam inspeção municipal. Sete propriedades optaram por não ter o próprio laticínio, fazendo parte de cooperativa; as outras propriedades optaram pela integração vertical. A distribuição é realizada por delivery e venda em mercados pequenos ou lojas próprias. Os maiores centros consumidores encontram-se nos estados do Rio Grande do Sul, Santa Catarina, São Paulo e Minas Gerais, havendo, porém, venda do produto em várias regiões do país. A principal característica do consumidor é o alto poder aquisitivo, fazendo-o buscar o produto em lojas especializadas. Pelo modelo das Cinco Forças de Porter, sugere-se que o sistema se apresenta sustentável e estável, sendo que o principal obstáculo para o crescimento são os produtos substitutos. Há falta de informações técnicas para melhorar a produção, assim, a verticalização do sistema e produção em cadeia curta parece ser a opção mais segura e rentável para os produtores. O modelo de estudo proposto permite analisar uma cadeia curta qualquer, caracterizando-a, com vistas à proposição de estratégias superiores de gestão e coordenação / The dairy sheep industry became economically important in South America in recent decades, but still little studied in Brazil. Milk is utilized for the production of cheese, providing added value, and it is considered a source of income to producers. As a starting point for the study of dairy sheep industry is proposed the description of the agro-industrial system for better understanding of the relationship between the agents. The study of the agri-food chains, targeting higher economic performance, uses microeconomic approaches as Economics of Transaction Costs (ETC), the Economics of Measurements Costs (EMC), Resource-Based View (RBV) and Entrepreneur Theory. Within the agribusiness, there are the \"short food supply chains\", forms of organization and marketing seeking the proximity between producers and consumers. This study aimed to describe the agribusiness of dairy sheep in Brazil, seeking to understand the strategies adopted by agents and propose a methodology to study the short food supply chains. The research was exploratory type and multi-case, through interviews with pre-formulated questionnaires. The agribusiness of dairy sheep was characterized as a short food supply chain system due to the approximation of the producer to the consumer having, in most cases, only one agent responsible for the different stages of the chain. The system is composed, in terms of technological transformation, in four major links: inputs, primary production, processing and distribution. The inputs are purchased in spot markets. It was identified 18 producing farms in the country. The predominant races were Lacaune and East Friesian, with an average of 1.17 liters of milk / animal / day, below the average potential for the races (2 liters). It was observed that 14 among the 18 properties had family labor. Among dairy products, four of them had federal inspection, three had state inspection and three had municipal inspection. Seven farms have chosen not to have the dairy itself but they were part of the cooperative; the other farms have opted for vertical integration. The distribution is carried out by delivery and sale in small markets or stores. The largest consumer centers are in the states of Rio Grande do Sul, Santa Catarina, São Paulo and Minas Gerais, however, there were sale of the product in various regions of the country. The main consumer characteristic is the high purchasing power, so they looked for the product in specialty stores. By the Porters five forces model, it is suggested that the system is sustained and stable and the main obstacle for growth are substitute products. There is a lack of technical information to improve production, so the verticalization of the system and production in a short chain system seems to be the safest and most costeffective option for producers. The proposed study model allows the analysis of any short food supply chain, characterizing it, with a view to proposing higher management strategies and coordination
15

Sistema agroindustrial do leite de ovelha no Brasil: proposta metodológica para estudo de cadeias curtas / Dairy sheep's agribusiness system in Brazil: methodological approach to the study of short food supply chains

Fernanda Ferreira dos Santos 03 June 2016 (has links)
A ovinocultura leiteira tornou-se importante economicamente na América do Sul nas últimas décadas, sendo ainda pouco estudada no Brasil. O leite é destinado à produção de queijo, proporcionando valor agregado, sendo considerado fonte de renda aos produtores. Como ponto de partida para o estudo da ovinocultura leiteira, é proposta a descrição do sistema agroindustrial (SAG) para a melhor compreensão das relações entre os agentes. O estudo das cadeias agroalimentares, visando desempenho econômico superior, utiliza abordagens da microeconomia como Economia dos Custos de Transação (ECT), Economia dos Custos de Mensuração (ECM), Visão Baseada em Recursos (VBR) e Teoria do Empreendedor. Dentro dos SAGs existem as cadeias agroalimentares curtas, formas de organização e comercialização que buscam a proximidade entre produtores e consumidores. Este trabalho teve como objetivo descrever o SAG do leite ovino no Brasil, buscando entender as estratégias adotadas pelos agentes e propor uma metodologia de estudo as cadeias curtas. A pesquisa foi do tipo exploratória e de multi-caso, por meio de entrevistas com questionários pré-formulados. O SAG do leite ovino foi caracterizado como um sistema em cadeia curta pela aproximação do produtor com o consumidor, possuindo, na maior parte das vezes, apenas um agente responsável pelas diferentes etapas da cadeia. O sistema é composto, em termos de transformação tecnológica, em quatro grandes elos: insumos, produção primária, agroindústria e distribuição, sendo os insumos adquiridos em mercados spot. Foram identificadas 18 fazendas produtoras no país. As raças predominantes eram Lacaune e East Friesian, com média de 1,17 litros de leite/animal/dia, abaixo da média potencial para as raças (2 litros). Observou-se que 14 entre as 18 propriedades apresentam mão de obra familiar. Dentre os laticínios, quatro possuíam inspeção federal, três possuíam inspeção estadual e três possuíam inspeção municipal. Sete propriedades optaram por não ter o próprio laticínio, fazendo parte de cooperativa; as outras propriedades optaram pela integração vertical. A distribuição é realizada por delivery e venda em mercados pequenos ou lojas próprias. Os maiores centros consumidores encontram-se nos estados do Rio Grande do Sul, Santa Catarina, São Paulo e Minas Gerais, havendo, porém, venda do produto em várias regiões do país. A principal característica do consumidor é o alto poder aquisitivo, fazendo-o buscar o produto em lojas especializadas. Pelo modelo das Cinco Forças de Porter, sugere-se que o sistema se apresenta sustentável e estável, sendo que o principal obstáculo para o crescimento são os produtos substitutos. Há falta de informações técnicas para melhorar a produção, assim, a verticalização do sistema e produção em cadeia curta parece ser a opção mais segura e rentável para os produtores. O modelo de estudo proposto permite analisar uma cadeia curta qualquer, caracterizando-a, com vistas à proposição de estratégias superiores de gestão e coordenação / The dairy sheep industry became economically important in South America in recent decades, but still little studied in Brazil. Milk is utilized for the production of cheese, providing added value, and it is considered a source of income to producers. As a starting point for the study of dairy sheep industry is proposed the description of the agro-industrial system for better understanding of the relationship between the agents. The study of the agri-food chains, targeting higher economic performance, uses microeconomic approaches as Economics of Transaction Costs (ETC), the Economics of Measurements Costs (EMC), Resource-Based View (RBV) and Entrepreneur Theory. Within the agribusiness, there are the \"short food supply chains\", forms of organization and marketing seeking the proximity between producers and consumers. This study aimed to describe the agribusiness of dairy sheep in Brazil, seeking to understand the strategies adopted by agents and propose a methodology to study the short food supply chains. The research was exploratory type and multi-case, through interviews with pre-formulated questionnaires. The agribusiness of dairy sheep was characterized as a short food supply chain system due to the approximation of the producer to the consumer having, in most cases, only one agent responsible for the different stages of the chain. The system is composed, in terms of technological transformation, in four major links: inputs, primary production, processing and distribution. The inputs are purchased in spot markets. It was identified 18 producing farms in the country. The predominant races were Lacaune and East Friesian, with an average of 1.17 liters of milk / animal / day, below the average potential for the races (2 liters). It was observed that 14 among the 18 properties had family labor. Among dairy products, four of them had federal inspection, three had state inspection and three had municipal inspection. Seven farms have chosen not to have the dairy itself but they were part of the cooperative; the other farms have opted for vertical integration. The distribution is carried out by delivery and sale in small markets or stores. The largest consumer centers are in the states of Rio Grande do Sul, Santa Catarina, São Paulo and Minas Gerais, however, there were sale of the product in various regions of the country. The main consumer characteristic is the high purchasing power, so they looked for the product in specialty stores. By the Porters five forces model, it is suggested that the system is sustained and stable and the main obstacle for growth are substitute products. There is a lack of technical information to improve production, so the verticalization of the system and production in a short chain system seems to be the safest and most costeffective option for producers. The proposed study model allows the analysis of any short food supply chain, characterizing it, with a view to proposing higher management strategies and coordination
16

An overview of the management practices for wool production amongst the communal farmers of the Hewu district in the Eastern Cape Province

Makapela, Mbulelo Joseph January 2008 (has links)
The research was conducted in the Hewu area situated between Queenstown (20 km) and Whittlesea (15km) in the Eastern Cape Province of South Africa. In this area communal farming is practiced. Livestock and livestock products (wool) are the main sources of income. The farmers are mainly farming with Merino and Döhne Merino sheep. The lack of management systems (production, reproduction and management) for communal farmers resulted into ineffective communal farming defining the research problem. The research objectives set were: • To establish production norms for wool sheep. • To establish reproduction norms for wool sheep. • To establish effective management practices for wool sheep farmers. • To examine key constraints of wool sheep farmers. The farmers shear their sheep every 12 months usually in October of every year. The average wool production per sheep is 2.17kg. The clip averages a fineness of 19.1-20 micron. That is far below the wool production of the commercial farmers of the Eastern Cape who are producing between 4kg to 5kg per sheep at an average growing period of 12 months. The lack of proper fencing and camps causes major reproduction problems. The lambing percentage of the ewes is 94.85 percent. The weaning percentage referring to the reproductive efficiency of the mated ewes is only 17.24 percent. The survival rate of the lambs born alive is only 18.18 percent. Reproduction is the biggest problem of communal farms. Effective livestock- and grazing management systems for communal areas are essential for the successful development of farmers on communal grazing areas. Unfortunately the Hewu farmers still have many problems effecting their wool production and the production of lambs.
17

Desenvolvimento de modelo computacional híbrido - baseado em agentes e em simulação de eventos discretos - para avaliação e planejamento da produção animal: uma aplicação na ovinocultura de corte / Development of hybrid computational model - agent based and discrete event simulation - for evaluation and planning of animal production: an application in the sheep meat industry

Reijers, Thayla Sara Soares Stivari 03 October 2016 (has links)
Realizar a análise econômica de uma produção agropecuária não é algo trivial, seja pela enorme heterogeneidade entre cada unidade produtiva, seja porque utiliza muitos recursos naturais, alguns de difícil mensuração. Há diversos métodos disponíveis para o cálculo do custo de produção, que é o indicador chave para a análise da viabilidade de um empreendimento. O desafio é permitir que a projeção da atividade no horizonte produtivo seja a mais real e dinâmica possível. A simulação computacional é atualmente uma das mais poderosas ferramentas de análise disponível para o planejamento, projeto e controle de sistemas complexos, e vem sendo cada vez mais utilizada e difundida. Simular compreende a elaboração de um método de experimentação que, através da construção de modelos de um sistema real, procura descrever comportamentos, construir teorias ou hipóteses por meio do observado e predizer comportamentos futuros. O uso de modelos de simulação, que incorporem o risco e a probabilidade dentro produção animal, pode ser uma alternativa tanto técnica - auxiliando na tomada de decisão, gestão e planejamento pecuário, quanto científica - permitindo a avaliação de efeitos de resultados da pesquisa e identificação de limitantes que podem incentivar o desenvolvimento de pesquisas futuras. O modelo de simulação híbrido - baseado em simulação de eventos discretos e baseado em agentes, aqui proposto - visou identificar coeficientes zootécnicos e os critérios de manejo que mais impactam a produção de ovinos de corte. Esse modelo de simulação computacional híbrido possui caráter dinâmico e probabilístico, com eventos marcados no tempo (estação de monta, gestação, parição, desmame, engorda, abate, entre outras) e complexos o suficiente para que seus agentes sofram alterações tanto no tempo quanto em resposta a ocorrência ou não das variáveis ligadas a eles. Os resultados dos experimentos e dos cenários estudados revelaram que dentre os índices zootécnicos das matrizes, a ocorrência de aborto gera maior impacto na taxa de abate e financeiramente na margem líquida operacional. Contudo, analisando as variáveis tanto para matrizes como para cordeiros, a mortalidade neonatal, até os cinco dias de vida dos cordeiros, demonstrou ser o ponto fundamental para a lucratividade da atividade. A estabilização do rebanho foi mais afetada pela presença de matrizes adultas no plantel, que culminaram no aumento no número de cordeiros por matriz. Os resultados da análise dos fluxos de caixa de 30 anos, a uma taxa mínima de atratividade de 6,17% aa, permitiram constatar que iniciar a atividade com número muito reduzido de matrizes é o cenário menos interessantes, com taxa interna de retorno negativa para o período de análise. O estudo do fluxo de caixa permitiu atribuir a 200 matrizes como o tamanho de rebanho inicial mais interessante (TIR = 3,30% aa). Assim, o uso de simuladores híbridos baseados em simulação de eventos discretos e baseados em agentes, para estudos na pecuária nacional, apresentou-se como ferramenta com grande potencial de contribuição, no sentido de permitir conhecer os resultados possíveis das diferentes combinações tecnológicas disponíveis. O modelo ainda permite ser utilizado como ferramenta de estudo e análise para a cadeia produtiva, contribuindo na orientação aos cientistas, auxiliando no direcionamento de seus esforços no desenvolvimento de futuras pesquisas / Conduct an economic analysis of agricultural production is not trivial, either by its enormous heterogeneity between each production unit, or because it uses many natural resources, some of which are difficult to measure. There are several methods available for calculating the cost of production, which is the key indicator for assessing the feasibility of a project. The challenge is to allow the projection of activity in the productive horizon in the most real and dynamic form as possible. The computer simulation is currently one of the most powerful analysis tools available for planning, design and control of complex systems and is being increasingly used and disseminated. Simulate includes the development of a method of testing by building models of a real system, that seeks to describe behaviors, build theories or hypotheses through noted and predicted future behaviors. The use of simulation models that incorporate uncertainty and probability in animal production can be both an alternative technique - assisting in decision-making, management and livestock planning; as scientific - allowing the evaluation of the research results of effects and identification of limiting that may encourage the development of future research. The model of hybrid simulation - based on discrete event simulation and on agent-based, proposed here - aimed to identify factors husbandry and management criteria that most affect the production of meat sheep. The model of hybrid computer simulation have dynamic and probabilistic characteristics, with events scheduled in time (breeding season, pregnancy, parturition, weaning, fattening, slaughter, etc.) and enough complexity that its agents be adversely affected both in time and in response to the occurrence or not of variables linked to them. The results of the experiments and the scenarios studied showed that among the zootechnical indexes of the sheep, the occurrence of abortion generates a greater impact on the slaughter rate and financially in the net operating margin. However, analyzing the variables for both sheep and lambs, neonatal mortality, up to the lambs\' five days of life, proved to be the fundamental point for the profitability of the activity. The stabilization of the herd was more affected by the presence of adult sheep in the herd, which culminated increasing the number of lambs per sheep. The results of the analysis of the 30-year cash flows, at a minimum attractiveness rate of 6.17% per year, showed that starting the activity with a very small number of sheep was the least interesting scenario, with a negative internal rate of return for the analysis period. The study of the cash flow allowed to assign to 200 sheep as the most interesting initial herd size (IRR = 3.30% per year). Thus, the use of hybrid simulators, based on discrete event simulation and agent-based for studies in national livestock, is presented as a tool with great potential to contribute, to allow knowing the possible outcomes of different combinations of available technology. The model also allows to be used as a study tool and assessment of different technological combinations for the production chain, contributing to the guidance of scientists, assisting their efforts in the development of future research
18

Qualidade e vida de prateleira de patê elaborado com subprodutos comestíveis do abate de ovinos. / Quality and shelf life of pâté made with edible by-products from slaughtered lamb.

Amaral, Deborah Silva do 20 April 2012 (has links)
Made available in DSpace on 2015-04-17T14:49:19Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1476200 bytes, checksum: 9adfb21edcaca9834a01f0b4db7401ca (MD5) Previous issue date: 2012-04-20 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Many edible meat by-products, produced from the lamb slaughter, are often wasted, although they represent excellent sources of many nutrients. The preparation of pâté may be an alternative to the use of this raw material, and contribute to the development of lamb sector by the offer of new products to the consumer market. The objective of this work was to produce and evaluate the quality and shelf life of a lamb pâté, made with the blood, liver and trimmed meat, packed in glass and polyamide casing, stored at 4±1 °C for 90 days. The formulation of the product was composed by 12% meat, 25% liver, 13% blood, 20% water and 30% fat, as well as spices and herbs. The lamb pâté was prepared in accordance with the requirements in the Brazilian legislation, regarding chemical and microbiological parameters, being able to use. It presented high iron content (9.0 mg/100g), important in the control of anemia. The levels of essential amino acids, found in 100g of the lamb pâté, exceeded the recommended daily allowances for adults, especially leucine, valine and histidine. The lamb pâté showed also a significant percentage of linoleic acid (16.68%), which is essential to the human body. The lamb pâté had good acceptability, whereas 55.6 % of the panelists indicated that they will probably buy it. The storage period showed good microbiological stability, but its shelf life was limited by the regression of the acceptability of sensory attributes, especially, overall impression and texture. The physico-chemical parameters of lamb pâté were affected by storage time, especially the instrumental texture, which indicated instability of emulsion during storage, and an increase in hardness, springiness and gumminess. Difference between the two packages used to the lamb pâté was detected only to the moisture, TBARS, hardness and gumminess parameters; however, there was no change in the microbiological and sensory quality of the product, this result highlights the advantages of the packages studied. In fact, this study suggests that the development of lamb pâté is a viable alternative to add value to the edible byproducts of lamb in order to obtain a product with high nutritional value. / Do abate ovino resultam diversos subprodutos comestíveis, os quais representam fonte nutricional e sensorial, sendo muitas vezes desperdiçados. A elaboração de patê apresenta-se como uma alternativa para o aproveitamento desta matéria-prima de baixo valor comercial, contribuindo para o desenvolvimento da ovinocultura, além da diversificação de seus produtos ao mercado consumidor. Neste aspecto, objetivou-se com este trabalho produzir, avaliar a qualidade físico-química, sensorial e a vida de prateleira de um patê, elaborado com o sangue, fígado e carne de ovinos, embalado em vidro e em tripa de poliamida, armazenado a 4±1°C durante 90 dias. A formulação do produto foi composta por 12% de carne, 25% de fígado, 13% de sangue, 20% de água e 30% de toucinho, além de especiarias e condimentos. O patê apresentou os requisitos exigidos na legislação Brasileira, quanto aos parâmetros químicos e microbiológicos, com elevado teor de ferro (9,0 mg/100g), importante no controle da anemia. Os níveis de aminoácidos essenciais encontrados em 100g da amostra superaram as quantidades diárias recomendadas para adultos, especialmente para leucina, valina e histidina. O patê ovino apresentou uma porcentagem significativa de ácido linoleico (16,68%), que é essencial para o organismo humano. O produto teve boa aceitação sensorial, visto que 55,6% dos provadores responderam positivamente a intenção de compra. Quanto ao período de armazenamento, o produto apresentou ótima estabilidade microbiológica, entretanto sua vida útil foi limitada pela regressão da aceitabilidade dos atributos sensoriais, principalmente, impressão global e textura. Em relação aos parâmetros físico-químicos, todos foram afetados pelo tempo de armazenamento, especialmente a textura instrumental, a qual indicou instabilidade da emulsão ao longo do armazenamento, com acréscimo da dureza, elasticidade e gomosidade. Verificou-se diferença significativa entre as amostras nas duas embalagens, apenas nas análises de umidade, TBARS, dureza e gomosidade, no entanto, não foi observada nenhuma alteração na qualidade microbiológica e sensorial do produto que destacasse vantagens entre as embalagens estudadas. Este estudo sugere que o desenvolvimento de patê é uma alternativa viável para agregar valor aos subprodutos comestíveis de ovinos, tendo em vista a obtenção de um produto com elevado valor nutricional.
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Desenvolvimento de modelo computacional híbrido - baseado em agentes e em simulação de eventos discretos - para avaliação e planejamento da produção animal: uma aplicação na ovinocultura de corte / Development of hybrid computational model - agent based and discrete event simulation - for evaluation and planning of animal production: an application in the sheep meat industry

Thayla Sara Soares Stivari Reijers 03 October 2016 (has links)
Realizar a análise econômica de uma produção agropecuária não é algo trivial, seja pela enorme heterogeneidade entre cada unidade produtiva, seja porque utiliza muitos recursos naturais, alguns de difícil mensuração. Há diversos métodos disponíveis para o cálculo do custo de produção, que é o indicador chave para a análise da viabilidade de um empreendimento. O desafio é permitir que a projeção da atividade no horizonte produtivo seja a mais real e dinâmica possível. A simulação computacional é atualmente uma das mais poderosas ferramentas de análise disponível para o planejamento, projeto e controle de sistemas complexos, e vem sendo cada vez mais utilizada e difundida. Simular compreende a elaboração de um método de experimentação que, através da construção de modelos de um sistema real, procura descrever comportamentos, construir teorias ou hipóteses por meio do observado e predizer comportamentos futuros. O uso de modelos de simulação, que incorporem o risco e a probabilidade dentro produção animal, pode ser uma alternativa tanto técnica - auxiliando na tomada de decisão, gestão e planejamento pecuário, quanto científica - permitindo a avaliação de efeitos de resultados da pesquisa e identificação de limitantes que podem incentivar o desenvolvimento de pesquisas futuras. O modelo de simulação híbrido - baseado em simulação de eventos discretos e baseado em agentes, aqui proposto - visou identificar coeficientes zootécnicos e os critérios de manejo que mais impactam a produção de ovinos de corte. Esse modelo de simulação computacional híbrido possui caráter dinâmico e probabilístico, com eventos marcados no tempo (estação de monta, gestação, parição, desmame, engorda, abate, entre outras) e complexos o suficiente para que seus agentes sofram alterações tanto no tempo quanto em resposta a ocorrência ou não das variáveis ligadas a eles. Os resultados dos experimentos e dos cenários estudados revelaram que dentre os índices zootécnicos das matrizes, a ocorrência de aborto gera maior impacto na taxa de abate e financeiramente na margem líquida operacional. Contudo, analisando as variáveis tanto para matrizes como para cordeiros, a mortalidade neonatal, até os cinco dias de vida dos cordeiros, demonstrou ser o ponto fundamental para a lucratividade da atividade. A estabilização do rebanho foi mais afetada pela presença de matrizes adultas no plantel, que culminaram no aumento no número de cordeiros por matriz. Os resultados da análise dos fluxos de caixa de 30 anos, a uma taxa mínima de atratividade de 6,17% aa, permitiram constatar que iniciar a atividade com número muito reduzido de matrizes é o cenário menos interessantes, com taxa interna de retorno negativa para o período de análise. O estudo do fluxo de caixa permitiu atribuir a 200 matrizes como o tamanho de rebanho inicial mais interessante (TIR = 3,30% aa). Assim, o uso de simuladores híbridos baseados em simulação de eventos discretos e baseados em agentes, para estudos na pecuária nacional, apresentou-se como ferramenta com grande potencial de contribuição, no sentido de permitir conhecer os resultados possíveis das diferentes combinações tecnológicas disponíveis. O modelo ainda permite ser utilizado como ferramenta de estudo e análise para a cadeia produtiva, contribuindo na orientação aos cientistas, auxiliando no direcionamento de seus esforços no desenvolvimento de futuras pesquisas / Conduct an economic analysis of agricultural production is not trivial, either by its enormous heterogeneity between each production unit, or because it uses many natural resources, some of which are difficult to measure. There are several methods available for calculating the cost of production, which is the key indicator for assessing the feasibility of a project. The challenge is to allow the projection of activity in the productive horizon in the most real and dynamic form as possible. The computer simulation is currently one of the most powerful analysis tools available for planning, design and control of complex systems and is being increasingly used and disseminated. Simulate includes the development of a method of testing by building models of a real system, that seeks to describe behaviors, build theories or hypotheses through noted and predicted future behaviors. The use of simulation models that incorporate uncertainty and probability in animal production can be both an alternative technique - assisting in decision-making, management and livestock planning; as scientific - allowing the evaluation of the research results of effects and identification of limiting that may encourage the development of future research. The model of hybrid simulation - based on discrete event simulation and on agent-based, proposed here - aimed to identify factors husbandry and management criteria that most affect the production of meat sheep. The model of hybrid computer simulation have dynamic and probabilistic characteristics, with events scheduled in time (breeding season, pregnancy, parturition, weaning, fattening, slaughter, etc.) and enough complexity that its agents be adversely affected both in time and in response to the occurrence or not of variables linked to them. The results of the experiments and the scenarios studied showed that among the zootechnical indexes of the sheep, the occurrence of abortion generates a greater impact on the slaughter rate and financially in the net operating margin. However, analyzing the variables for both sheep and lambs, neonatal mortality, up to the lambs\' five days of life, proved to be the fundamental point for the profitability of the activity. The stabilization of the herd was more affected by the presence of adult sheep in the herd, which culminated increasing the number of lambs per sheep. The results of the analysis of the 30-year cash flows, at a minimum attractiveness rate of 6.17% per year, showed that starting the activity with a very small number of sheep was the least interesting scenario, with a negative internal rate of return for the analysis period. The study of the cash flow allowed to assign to 200 sheep as the most interesting initial herd size (IRR = 3.30% per year). Thus, the use of hybrid simulators, based on discrete event simulation and agent-based for studies in national livestock, is presented as a tool with great potential to contribute, to allow knowing the possible outcomes of different combinations of available technology. The model also allows to be used as a study tool and assessment of different technological combinations for the production chain, contributing to the guidance of scientists, assisting their efforts in the development of future research
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Qualidade da carne de cordeiros suplementados com vitamina E / Lamb meat quality supplemented with vitamin E

Gilmara da Silva Melo, Gilmara 11 December 2015 (has links)
Submitted by biblioteca unifenas (biblioteca@unifenas.br) on 2016-05-06T13:19:09Z No. of bitstreams: 1 Gilmara da Silva Melo Dissertacao.pdf: 988532 bytes, checksum: d457e85e340065bc994acfb16c3eb9cb (MD5) / Made available in DSpace on 2016-05-06T13:19:10Z (GMT). No. of bitstreams: 1 Gilmara da Silva Melo Dissertacao.pdf: 988532 bytes, checksum: d457e85e340065bc994acfb16c3eb9cb (MD5) Previous issue date: 2015-12-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The sheep industry in Brazil is presented as a promising activity, not only for increased consumption of meat of this species, but also the future possibility that sees both the national and international market. Among many factors that can contribute to the consolidation of this activity, the quality of meat is the main factor. Although the demand for lamb is high, supply is low and unstable, being a limiting factor in the marketing of this product in addition to the lack of concise information of the quality characteristics and physical-chemical profile. Based on the above, the aim of this research was to determine the pH, color, tenderness, weight loss by cooking, water holding capacity and profile of fatty acids from lamb supplemented with vitamin E. The experiment was conducted in partnership with the Animal Science Department of Universidade Federal de São João del Rei (UFSJ) and analyzes were sent for analysis to the Department of Food science at the Universidade Federal def Lavras and Meat Technology Laboratory of the Universidade Estadual Paulista, campus Jaboticaba. Twelve Texel lambs were used with initial average weight of 25 kg and 42 kg final. And the diet consisted of hay Tifiton 85, ground corn, soybean meal and commercial mineral supplement formulated according to recommendations of NRC (2007), with or not vitamin E. The experimental design was completely randomized with two treatments and six replications. Data were analyzed by the GLM procedure of the SAS (2001) and the averages compared by test T at 5% probability. In this study, the use of vitamin E depreciated the quality of sheep meat. / A ovinocultura de corte no Brasil apresenta-se, como uma atividade promissora, não somente pelo aumento no consumo da carne desta espécie, mas também pela possibilidade futura de uma carne de qualidade, que se vislumbra tanto para o mercado nacional como internacional. Entre os vários fatores que podem contribuir para a consolidação desta atividade, a qualidade da carne é a principal. Embora a demanda pela carne ovina seja elevada, a oferta é baixa e instável, sendo um fator limitante na comercialização deste produto, além da carência de informações sobre as características de qualidade e perfil físico-químico. Com base no exposto, objetivou-se com esta pesquisa determinar o pH, cor, maciez, perda de peso por cozimento, capacidade de retenção de água e perfil de ácidos graxos da carne de cordeiros suplementados com vitamina E. O experimento foi conduzido em parceria com o Departamento de Zootecnia da Universidade Federal de São João Del Rei (UFSJ) e as amostras foram enviadas para análise ao Departamento de Ciência dos alimentos da Universidade Federal de Lavras e ao Laboratório de Tecnologia de Carnes da Universidade Estadual Paulista, Câmpus de Jaboticabal. Foram utilizados 12 cordeiros da raça Texel com peso inicial médio de 25 Kg e final de 42 Kg. A dieta composta foi feno de Tifiton 85, milho moído, farelo de soja e suplemento mineral comercial, formulada segundo recomendações do NRC (2007), acrescida ou não de vitamina E. O delineamento experimental utilizado foi o inteiramente casualizado com dois tratamentos e seis repetições. Os dados foram analisados pelo procedimento GLM do SAS (2001) e as médias comparadas pelo teste t, a 5% de probabilidade. Neste estudo, a utilização da vitamina E depreciou a qualidade da carne ovina.

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