Search

The objective of this study was to evaluate the influence of thermal stress indices and minimum temperature on the semen quality of dairy Gyr bulls and to determine whether the minimum night temperature is able to balance the thermal stress that occurred during the day. A total of 922 semen samples were collected from 391 bulls aged between 15 and 49 months, which participated in progeny pretest trials, from December 2011 to April 2017. Semen characteristics (ejaculate volume, gross motility, sperm motility, sperm vigor, sperm concentration, and percentage of total defects) and scrotal circumference were analyzed. Meteorological data were recorded daily by the National Institute of Meteorology. The analyses were carried out using mixed models. The following fixed effects were included in the model: test, month of sample collection, scrotal circumference, the age of the bull at sampling as covariate (linear regression), and the climatic variables (equivalent temperature index [ETI], temperature and humidity index [THI], or minimum temperature). The effect of the bull nested within the test was included in the model as a random effect. Two periods were considered to evaluate the effect of the climatic variables on sperm quality: 7 days before collection (period 1) and the day of collection (period 2). There was an effect of ETI on sperm vigor and concentration in both periods and on volume and percentage of total defects only in the second period. The THI exerted a significant effect on volume in both periods and on sperm motility and concentration only in the second period. There was an effect of the minimum temperature on ejaculate volume, sperm motility, sperm concentration, and percentage of total defects only in the second period, which corresponds to the day of semen collection. Taken together, the results show that there was sufficient thermal stress to negatively affect semen quality. However, the minimum temperature during the night was a significant factor that balanced these negative effects of THI and ETI on semen traits of Gyr bulls.

Made available in DSpace on 2022-04-28T19:50:04Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Soil quality indicators may have different seasonal trends during the year. The hypothesis of this study was that sowing maize and marandu palisadegrass with the presence of grazing animals might cause short-term changes in soil indicator responses. We compared four intercropping techniques: ICLS-1: maize plus marandu palisadegrass sown simultaneously, without herbicide; ICLS-2: maize plus marandu palisadegrass sown simultaneously, with herbicide; ICLS-3: maize plus marandu palisadegrass in lagged sowing (i.e., marandu palisadegrass sown 20 days after maize sowing); ICLS-4: maize plus marandu palisadegrass sown simultaneously (palisadegrass on the rows and inter-rows, with herbicide). Two control treatments in monoculture (i.e., grass and maize monocultures) represented the conventional systems. The soil was sampled three times over a one-year period, for the evaluation of carbon and nitrogen fractions as affected by seasonal variability. Results indicated that ICLS-1 and ICLS-4 enhanced soil quality more quickly during the seasonal variation. The ICLS-2 negatively affected microbial biomass (22%), resulting in reduced labile carbon (43%), carbon management index (33%), and potentially mineralizable nitrogen (20%). Labile carbon and the carbon management index were more sensitive and efficient indicators for verifying soil quality changes in the short-term. Results indicated that there is large variability in these soil indicators during the annual cycle, and further studies are needed to verify the effects of the tested systems on different soil nitrogen fractions and how they affect available nitrogen in the short-term. However, potentially mineralizable nitrogen can provide positive insights for short-term changes in the soil. Universidade Estadual Paulista “Júlio de Mesquita Filho” Faculdade de Ciências Agrárias e Veterinárias, SP University of Florida Institute of Food and Agricultural Sciences North Florida Research and Education Center Instituto de Zootecnia Centro de Pesquisa de Bovinos de Corte, SP Universidade de São Paulo Faculdade de Medicina Veterinária e Zootecnia, SP Universidade Estadual Paulista “Júlio de Mesquita Filho” Faculdade de Ciências Agrárias e Veterinárias, SP CAPES: 001 FAPESP: 2014/24514-6 FAPESP: 2017/50339-5

The objective of this study was to evaluate the potential of improve economic value of integrated crop-livestock systems in comparison to conventional systems specialized in monoculture. Empirical studies have demonstrated the environmental benefits of integrated crop-livestock systems, however the potential for creating economic value these systems are controversial, especially in emerging countries, where the necessity to expand the food supply needs be associated with better land use. This research evaluated six models of integrated systems and two conventional systems (corn grain production and pasture beef cattle production) in the south-eastern region of Brazil for two years. The models were conducted in an experiment to replicate the main management possibilities in the integrated systems. We show for the first time the economic impact analysis combined the risk optimization and discounted cash flow techniques based on Monte Carlo simulation, considering the price and productivity uncertainties of each system. Results indicated that, for the indicators of added value and return on investment, integrated crop-livestock systems had an economic advantage when compared to conventional systems. It was also found that integrated crop-livestock systems needed a smaller operational area for the economic break-even point to be reached.

Os profissionais envolvidos nas cadeias de produção animal e vegetal se deparam com um cenário atual de contradições. De um lado, o aumento pela demanda de alimentos, de outro, as pressões sociais que questionam o modo como é conduzida a produção. Neste contexto, os sistemas integrados podem ser uma importante estratégia. A integração lavoura-pecuária (ILP) consiste na implantação de diferentes sistemas produtivos para a produção animal e vegetal na mesma área, em plantio consorciado, sequencial ou rotacional. Os benefícios mais divulgados em relação aos sistemas de ILP são os agronômicos ou produtivos, que são consequência da melhoria da qualidade do solo e maior controle de pragas. Contudo, para que os sistemas de ILP sejam adotados em escala comercial, representando de fato uma alternativa para a produção de alimentos, é necessário que a ciência aborde também questões econômicas e gerenciais envolvidas na adoção e manutenção dos sistemas de ILP.

The objective with this study was to calculate the total cost of maize production and beef cattle in permanent pasture activities in separate production systems (conventional) and integrated systems (maize production plus beef cattle), as well as to verify economic gains explained by the economy of scope. The first step for the development of the research was to obtain field experimental data. Six experimental treatments were studied: corn grain production, beef cattle in permanent pasture, and four integrated systems based on different crop and pasture sowings. The second step consisted in the collection, calculation, and allocation of variable and fixed costs to estimate costs of production in the systems. The crop-livestock integration showed economic gains in relation to conventional systems, which can be explained by the dilution of fixed costs and the presence of shareable inputs, resulting in economy of scope. It was also possible to demonstrate that total unit costs of both crop and livestock were lower in crop-livestock integration, showing that integrated systems resulted in economic benefits as compared with conventional ones.

Investigating factors that could affect milk production of cows is an important way to improve the efficiency of production systems. This purpose of this study was to verify and quantify the influence of calf sex on milk production and lactation length in herds of Holstein, Gir, and Guzera cows. Data from 10,780 lactations of 4,807 Holstein cows that calved between 2001 and 2013; 18,898 lactations of 13,172 Gir cows that calved between 1985 and 2013; and 5,277 lactations of 3,972 Guzera cows that calved between 1987 and 2013 were used. Both the accumulated 305-day milk yield (P305) and the length of the lactation period up to 305 days (DL305) were evaluated. Analysis of variance was performed by the least squares method using the GLM procedure in the SAS statistical program. The P305 was not influenced by the sex of the calf in the Holstein breed. However in the zebu breeds (Gir and Guzera), both P305 and DL305 were significantly affected (P < 0.01) by the sex of the calf, with higher production and average length of lactation in cows that calved males. In addition, a significant difference was also nested within sex of calf and age at first calving (P < 0.05) in the Gir breed. The results indicate that for the zebu breeds, calf sex influences production characteristics.

O monocultivo, delineamento da produção agropecuária mais tradicional, desde a Revolução Verde, têm sido relacionado ao desequilíbrio ambiental de ecossistemas, e escassez de recursos naturais. Neste contexto, sistemas integração lavoura-pecuária (ILP) tem se mostrado promissores em relação à benefícios ambientais e produtivos, quando comparada a sistemas de monocultivo. Existe, todavia, poucos trabalhos que abordam os benefícios econômicos potenciais dos sistemas ILP. O objetivo desta dissertação foi desenvolver análise econômica e financeira da produção de milho grão e bovinos de corte em sistemas de monocultivo e ILP. A primeira etapa para o desenvolvimento da pesquisa foi a coleta de dados do projeto intitulado Impacto ambiental, produtividade e viabilidade econômica de sistemas de monocultivo e integrado de lavoura pecuária, financiado pela Fapesp (Processo Nº 2014/24514-6) delineado a partir de seis tratamentos experimentais: T1) Monocultivo de milho grão; T2) Monocultivo Brachiaria brizantha cv. Marandu; T3) Integração entre milho e Brachiaria brizantha cv. Marandu, semeados simultaneamente; T4) Integração entre milho e Brachiaria brizantha cv. Marandu, semeados simultaneamente, com aplicação de herbicida; T5) Integração entre milho e Brachiaria brizantha cv. Marandu, tendo sido o capim semeado na adubação de cobertura do milho; T6) Integração entre milho e Brachiaria brizantha cv. Marandu, semeados simultaneamente, na linha e entrelinha do milho, com aplicação de herbicida. A segunda etapa foi a cálculo dos custos variáveis dos tratamentos experimentais. A terceira etapa consistiu no cálculo do custo total de produção de sistemas de produção representativos comerciais, que replicassem os manejos e tecnologias utilizados nos tratamentos experimentais. A quarta etapa consistiu na análise financeira, tendo sido o valor presente líquido (VPL), a taxa interna de retorno (TIR) e o PayBack os indicadores de tomada de decisão. O software Microsoft Excel® foi utilizado para o cálculo dos custos de produção, construção do fluxos de caixa e estimativa dos indicadores de viabilidade. Os resultados indicaram ganhos econômicos da ILP, em relação ao monocultivo, explicados pela teoria da economia de escopo. As fontes da economia de escopo identificadas nessa pesquisa foram: diluição de custos fixos e complementariedades técnicas compartilhadas. Os custos de produção unitários da lavoura e da pecuária foram menores na ILP do que nos sistemas de monocultivo. Os sistemas ILP e o monocultivo de milho grão foram considerados economicamente viáveis, com base no VPL, TIR e PayBack. O VPL do sistema ILP foi maior do que do sistema de monocultivo de milho, o que demonstrou outro benefício econômico dos sistemas integrados, se comparados ao monocultivo. A pecuária monocultivo foi economicamente inviável, baseado nos mesmos indicadores de viabilidade econômica. Monoculture farming, the traditional agriculture approach since the Green Revolution, has been associated with the environmental imbalance of ecosystems and with the scarcity of natural resources. Within this context, integrated crop-livestock (ICL) systems have shown to be promising in terms of environmental and productive benefits when compared to monoculture systems. However, few studies have addressed the potential economic benefits of ICL systems. The objective of this dissertation was to perform an economic and financial analysis of corn grain and beef cattle production in monoculture and ICL systems. The first phase of the study consisted of the collection of data from the project entitled Environmental impact, productivity and economic viability of monoculture and integrated crop-livestock systems, financed by Fapesp (2014/24514-6) and designed in six experimental treatments: T1) corn monoculture; T2) Palisade grass (Brachiaria brizantha cv. Marandu) monoculture; T3) corn plus Palisade Grass sown simultaneously; T4) corn plus Palisade Grass sown simultaneously plus herbicide; T5) Palisade grass sown at topdressing corn; T6) Palisade Grass sown at the line and inter-line of corn. In the second phase, the variable costs of the experimental treatments were calculated. The third phase consisted of calculating the total production cost of representative commercial production systems that replicate the managements and technologies used in the experimental treatments. The fourth phase consisted of financial analysis using the net present value (NPV), internal rate of return (IRR), and payback as indicators for decision making. The Microsoft Office Excel software was used for the calculation of production costs, cash flow definition, and estimation of viability indicators. The results indicated economic gains of the ICL system compared to monoculture, explained by the theory of economies of scope. The sources of economies of scope identified in this study were the dilution of fixed costs and shared technical complementarities (fertilizers for example). The unit production costs of livestock and crop were lower in the ICL than in the monoculture system. The ICL systems and corn grain monoculture were considered economically viable based on NPV, IRR, and PayBack. The NPV of ICL systems was bigger than the NPV of corn grain monoculture, which has shown another economic benefit of the integrated systems compared to monoculture. The livestock monoculture system proved to be economically unviable because of the negative NPV and IRR below the minimum attractive rate considered.

The objectives of this study were to explore the relationship between plant variables using correlation and principal component analysis; to explore the chemical composition patterns in a subgroup of plants using cluster analysis; and to compare the prediction ability between a linear model using only the SPAD index as a predictor with multiple linear regression and neural networks with the SPAD index, morphological and climatic measurements as predictors of the chemical composition of Urochloa brizantha leaves and stems. The experimental design was in blocks (three blocks) with five treatments, totaling 15 experimental units. Chlorophyll measurements and forage sampling were performed every 28 d. The variables used in the statistical analysis were: percentage of leaves, stems and dead plant material; plant height; relative chlorophyll (SPAD); percentage of acid detergent fibre in leaves and stems (ADF.L, ADF.S); percentage of neutral detergent fibre in leaves and stems (NDF.L, NDF.S); lignin percentage in leaves and stems (LIG.L, LIG.S); and nitrogen content in leaves and stems (N.L, N.S). The climatic variables were monthly average minimum and maximum temperatures and monthly rainfall. The correlation between SPAD with N.L and N.S was 0.56 and 0.49, respectively, and between N.L with N.S was 0.87. The correlation between the observed and predicted responses using simple linear regression, with SPAD as the predictor, ranged from 0.198 for ADF.L to 0.577 for N.L. However, the correlations ranged from 0.497 for LIG.L to 0.759 for N.S when multiple regression was used with other predictors, besides SPAD. The prediction accuracy using neural networks ranged from 0.501 for LIG.L to 0.863 for N.S and was higher than multiple regression for all characteristics except LIG.L and LIG.S. Principal component analysis efficiently condensed the most important information of the 13 original variables measured in the plants into three principal components due to the redundancy of information of the variables. According to the cluster analysis, plants with higher nitrogen content in their leaves and stems presented lower fibre contents and dead plant material, and were denser than those with lower nitrogen content. Multiple linear regression can be used to predict lignin content in leaves and stems and neural networks must be used to predict nitrogen and the other fibre contents. SPAD is an important predictor of nitrogen content in tropical pastures, but it is not the only predictor that must be used in regression models and neural networks; morphological characteristics and climatic conditions increase the prediction accuracy of the models.

Farm schools offer a learning environment for the education of students in Agricultural Technical Programs and offer this program adopting boarding systems (“farm-boarding schools” or “FBS”). The big challenge in FBS is balancing education and production, that is, provide resources for practical classes and at the same time provide food for farm residents from a pre-defined budget by the sponsoring institution. The aim of this paper is to present a linear programming model to plan and optimize FBS production and supply. The model was applied in two FBS in Brazil. The model developed could show the complexity of the FBS system, which features a variety of productions and the interactions among them. The modeling process presented positive results from a technical and managerial point of view, including people management. The formulated model showed an optimized scenario which extended the managers’ analysis horizon and allowed safer decision making. The system’s complexity hampers dialogue between the farm-boarding school team and managers. From the modeling process and the standardization of data and generated results, there was a greater safety margin to present investment proposals and analyzes, accelerating the decision-making process, which was a positive addition to the system.

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T19:07:48Z No. of bitstreams: 1 S1516-35982011001000017.pdf: 334086 bytes, checksum: 969b1d1f9d18d9fae0caf7cbe6e2b4ae (MD5) Made available in DSpace on 2013-08-22T19:07:48Z (GMT). No. of bitstreams: 1 S1516-35982011001000017.pdf: 334086 bytes, checksum: 969b1d1f9d18d9fae0caf7cbe6e2b4ae (MD5) Previous issue date: 2011-10-01 Made available in DSpace on 2013-09-30T18:02:43Z (GMT). No. of bitstreams: 2 S1516-35982011001000017.pdf: 334086 bytes, checksum: 969b1d1f9d18d9fae0caf7cbe6e2b4ae (MD5) S1516-35982011001000017.pdf.txt: 32381 bytes, checksum: bba33578c705577fc975fe54a689d16e (MD5) Previous issue date: 2011-10-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T13:18:55Z No. of bitstreams: 2 S1516-35982011001000017.pdf: 334086 bytes, checksum: 969b1d1f9d18d9fae0caf7cbe6e2b4ae (MD5) S1516-35982011001000017.pdf.txt: 32381 bytes, checksum: bba33578c705577fc975fe54a689d16e (MD5) Made available in DSpace on 2014-05-20T13:18:55Z (GMT). No. of bitstreams: 2 S1516-35982011001000017.pdf: 334086 bytes, checksum: 969b1d1f9d18d9fae0caf7cbe6e2b4ae (MD5) S1516-35982011001000017.pdf.txt: 32381 bytes, checksum: bba33578c705577fc975fe54a689d16e (MD5) Previous issue date: 2011-10-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) O objetivo neste estudo foi estimar os níveis ótimos de lisina digestível em rações para frangos de corte em crescimento (22 a 35 dias) e terminação (35 a 42 dias) com base na análise econômica da alimentação. Foram conduzidos dois experimentos, cada um com 600 frangos de corte machos da linhagem Cobb 500 distribuídos em delineamento inteiramente casualizado, com cinco tratamentos e seis repetições de 20 aves. em cada fase, os tratamentos consistiram de níveis crescentes de lisina digestível nas rações. Os dados de conversão alimentar foram submetidos à análise de variância e posteriormente a análises de regressão utilizando-se um modelo não-linear exponencial. Com base nas equações exponenciais ajustadas para cada fase de criação, foram calculadas a variação do custo com alimentação e a margem por kg de ganho de peso. em cada fase, foi considerado nível ótimo de lisina digestível aquele capaz de proporcionar o menor custo com alimentação e a maior margem por kg de ganho de peso. Considerando o preço da L-lisina HCl (78,5%) de R$ 11,78, os níveis ótimos de lisina digestível nas rações de crescimento e terminação são de 1,150 e 0,980%, respectivamente. Entretanto, se o preço desta fonte cristalina aumentar para R$ 14,13, os níveis ótimos nas rações reduzirão para 1,11 e 0,950%, respectivamente. The objective of this study was to estimate the optimum digestible lysine levels in diets for broilers on growing (22 to 35 days) and finishing (35 to 42 days) phases, based on economic analysis of food. Two experiments were conducted, each one using 600 Cobb 500 male broilers, distributed in a completely randomized design with five treatments and six replicates of 20 birds. Treatments consisted of increasing digestible lysine levels in the diet. The feed:gain relation data were submitted to ANOVA and to regression analyses using an exponential model. Based on adjusted equations for each phase, the change in food cost and margin per kg of weight gain was calculated. At each phase the optimum lysine level was considered as one to provide the lowest food cost and higher margin per kg of weight gain. Considering the price of L-lysine HCl (78.5%) of R$ 11.78, the optimum lysine levels in diets of growing and finishing poultry were estimated at 1.150 and 0.980% respectively. However, if the price of this source rises to R$ 14.13, the optimum lysine levels in diets will be reduced to 1.11 and 0.950% respectively. UNESP FCAV Universidade Federal do Maranhão Centro de Ciências Agrárias e Ambientais UNESP FCAV Departamento de Zootecnia Universidade Federal da Paraíba Departamento de Zootecnia Universidade Estadual Paulista Centro de Aqüicultura Universidade Federal do Piauí (FUFPI) Departamento de Zootecnia UNESP FCAV UNESP FCAV Departamento de Zootecnia Universidade Estadual Paulista Centro de Aqüicultura