Fontes proteicas para vacas leiteiras

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise numérica de uma geometria de coletor solar para sistemas de aquecimento de água

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Dinâmica não linear e controle de um sistema vibratório modelado com memória de forma e, excitado por fontes de energia do tipo ideal e não ideal

Pós-graduação em Engenharia Mecânica - FEB

Biohidrogenação microbiana e o fluxo duodenal de ácidos graxos do rumen em novilhos de corte suplementados com fontes lipídicas em dietas contendo glicerina

Pós-graduação em Zootecnia - FCAV

Levantamento de coeficientes de desempenho de refrigeradores domésticos associados a armazenador térmico

Pós-graduação em Engenharia Mecânica - FEB

Diferentes fontes de carboidratos em rações para leitões desmamados com diferentes pesos: pH e microbiota do trato gastrintestinal

Forty eight piglets from a commercial strain weaned at an average age of 21 days were used in order to evaluate effects of carbohydrates sources (lactose or maltodextrin) and the weights of piglets at weaning on the stomach pH, colon and rectum contents, and the amount of total coliform, Escherichia coli and Lactobacillus spp in digesta of ileum and cecum. The experiment was conducted in a randomized block design and analyzed in split plot, considering class of weight and carbohydrates as main plots and the slaughter age of animal as sub-plots. The stomach pH and intestinal contents were not influenced by the diets provided as well as the amount of total coliform. It was found that the presence of lactose in the feed decreased counts of Escherichia coli and Lactobacillus ssp in the ileum. Regarding the class of weight, the lighter piglets had lower counts of Escherichia coli and Lactobacillus. The maltodextrin can be used as an alternative to replace the lactose in the diet, regardless of the piglets weight at weaning, as it does not adversely affect the pH and the Lactobacillus population in the gastrointestinal tract.

Custos energéticos do agroecossistema pinhão-manso e milho: comparativo entre o sistema de condução sequeiro e o irrigado

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação energética econômica da cultura do milho em assentamento rural, Iperó-SP

This paper, having as a hypothesis that greater energetic inputs don't keep ratio with economical outputs, has tried to study the economical and energetic flows in the maize cultivation to several production systems used in Ipanema Settling Area I, having as analysis instrument the indexes of Cultural, Energetic, Economical efficiency, which were added to the methodological proposal of Cultural Economical and Energetic Economical Efficiency indexes, built for probability settings. Four different systems have been identified: "A", "B", "C" and "D". The energetic expenditure were, respectively, 4,836.19 MJ x ha-1, 4,4647.17 MJ x ha-1, 4,639.49 MJ x ha-1 and 4,450.47 MJ x ha-1. In "A", where the use of machines is more intensive, the participation of biological source energy was 23.26%, whereas the ones of fossil origin are 76.74%. The "D" system has the greatest Cultural Efficiency, with average index of 16.26, whereas "A" showed the lowest Cultural Efficiency indexes, with average values of 14.83. For the analysis of the Energetic Efficiency, that indicates the dependence of energy from non renewable sources, the highest index was the "D" system with an average index of 53.84. The Economical Efficiency Indexes, which ranged from 1.84 to 1.96, show that all systems are efficient. The "D" system, with index equal to 8.84, showed the highest index of Economical Cultural efficiency. The Economical Energetic analysis for "A", "B", "C" and "D" systems, has resulted, respectively, in the following indexes: 21.14 ; 23.86 ; 22.87 and 29.26. Through the outcome analysis, it was concluded that the more intensive use of energy from nonrenewable sources ("A" system) didn't necessarily mean a higher efficiency when compared to "D" (labor intensive), what comes to prove the paper's initial hypothesis.

Eficiência energética e econômica da produção de leite bovino em explorações familiares no município de Pardinho, região de Botucatu- SP

The study aimed to analyze the energy and economic efficiency rate family farms producing milk in the county of Pardinho, Sao Paulo State. The criteria used to define producers in this study is that outlined by the Brazilian agricultural credit system FEAP (Fund Expansion of Agribusiness Paulista). Through primary data, obtained by verbal reports, the agroecosystem technical itineraries were re-established, detailing the process applied, machinery, implements, equipment, supplies and manual work. These were transformed into energy and economic units, which allowed determining the established connection between energy economics outputs and inputs. The hypothesis of this study is that the energetic expenditure may be coincidental with economic expenditures. The energetic and economic flows were analyzed, using a structure of expenditures, by type, source and form of gross energy, as well as the energetic point of view. Four producers were found to have different technical itineraries. Producers 1 and 2 achieved the highest energy and economic efficiency rates. The producer with the lowest efficiency rates was producer 4. The energy sources not renewable like chemical fertilizers were the most used reaching an average of 82.9% for the energy and 52.86% for the economic expenditures. When comparing energy and economic efficiency it is possible to verify that both forms of analysis are close, obtaining a broader idea about energy resources allocation.

Avaliação energética econômica do agroecossistema algodão: uma abordagem entre sistemas familiares de produção do Paraguai e do Brasil

The objective of this work was to evaluate the energy and economic efficiency indexes per unit of cotton agro-ecosystem area in family production systems of Paraguay and Brazil; and, to establish a relationship between the energy and economic. Typologies presented by the Program to Support Small Cotton Holdings (Paraguay), and by the National Program for Strengthening Family Agriculture (Brazil). Family systems of the two countries were identified; these are located from Paraguay (San Juan–CA) and from Brazil (Leme–SP). To construct the energy expenditure structure of the cotton agro-ecosystem, as well as to assess the economic efficiency, the mean values obtained were considered, when they presented similarities in production systems and they were within the typology proposed in this study. From the technical itinerary observed the Paraguayan agro-ecosystem depended (fossil fuel 56.76%) and industrial source (35.99%). Thus, the energy balance of the agricultural stage was established, which attained a value of 17,740.69 MJ ha-1; an energy efficiency of 5.28, and a cultural efficiency of 3.04. The Brazilian agro-ecosystem depended on energy from industrial source (insecticides 39.82%) and from fossil fuel (33.59%); it reached an energy balance of 19,547.88 MJ ha-1; an energy efficiency of 2.12, and a cultural efficiency index of 0.71. In the economic and energy indicator ratio, with regard to the months referring to the harvest time, that is to say, March, April, and May, the maximum economic efficiency indicator of paraguay was attained in the month of May (1,00), and from Brazil in the month of May (1,71). Both production systems analyzed were presented efficient, however, dependent of external circumstances and non-renewable energy sources.

Valiação energética e econômica do agroecossistema algodão: uma abordagem entre sistemas familiares de produção do Paraguai e Brasil

The objective of this work was to evaluate the energy and economic efficiency indexes per unit of cotton agro-ecosystem area in family production systems of Paraguay and Brazil; and, to establish a relationship between the energy and economic. Typologies presented by the Program to Support Small Cotton Holdings (Paraguay), and by the National Program for Strengthening Family Agriculture (Brazil). Family systems of the two countries were identified; these are located from Paraguay (San Juan–CA) and from Brazil (Leme–SP). To construct the energy expenditure structure of the cotton agro-ecosystem, as well as to assess the economic efficiency, the mean values obtained were considered, when they presented similarities in production systems and they were within the typology proposed in this study. From the technical itinerary observed the Paraguayan agro-ecosystem depended (fossil fuel 56.76%) and industrial source (35.99%). Thus, the energy balance of the agricultural stage was established, which attained a value of 17,740.69 MJ ha-1; an energy efficiency of 5.28, and a cultural efficiency of 3.04. The Brazilian agro-ecosystem depended on energy from industrial source (insecticides 39.82%) and from fossil fuel (33.59%); it reached an energy balance of 19,547.88 MJ ha-1; an energy efficiency of 2.12, and a cultural efficiency index of 0.71. In the economic and energy indicator ratio, with regard to the months referring to the harvest time, that is to say, March, April, and May, the maximum economic efficiency indicator of paraguay was attained in the month of May (1,00), and from Brazil in the month of May (1,71). Both production systems analyzed were presented efficient, however, dependent of external circumstances and non-renewable energy sources.

Viabilidade econômica do uso do biogás proveniente da suinocultura em substituição a fontes externas de energia

The swine culture potentially generates waste with high organic load and pollutants, being responsible for the spread of pathogens, contamination of rivers, groundwater and soils, besides it produces foul odors and emit greenhouse gases. However, the high amount of organic matter, which expresses the amount of pollutant load, reflects the energetic potential of these wastes used as raw material in biogas generation through technology of digesters. The properly use of theses digesters provides the production of clean energy and promotes the conservation of the environment. The economic viability of the implantation of an Indian model digester on a small swine farm was verified based on the value from initial investments of deployment, maintenance costs, depreciation, and on the interest and revenues arising from the system. Besides, the amount of biogas produced daily and the average consumption of biogas by the most common used devices such as refrigerator, stove, water heater, and generator of electricity was calculated.. For a backdrop of 10 years, the results of economic indicators NPV of BRL 57,598.95, IRR of 48.38%, Simple Payback of 2.06 years, and Discounted Payback of 2.3 years, demonstrated a favorable outlook for the use of this technology, with the possibility to generate economic, social and environmental benefits.

Análise energética na agricultura: ferramenta importante para a produção agrícola mais sustentável

A produção de alimentos e matérias-primas é considerada um dos maiores desafios da atualidade. Assim, os impactos gerados pela atividade da agricultura são muitos, como por exemplo, erosão dos solos, poluição de águas doces e geração de resíduos. Com isso faz-se necessário o desenvolvimento de tecnologias para promover a redução desses impactos. O presente trabalho tem como objetivo apresentar e discutir análises energéticas em sistemas de produção agrícola como uma ferramenta capaz de destacar a dependência dos agroecossistemas de energia externa e de fontes não renováveis, particularmente de fontes fósseis. Assim, com o uso dessa ferramenta, alternativas para uma produção agrícola com menos impacto ambiental pode ser alcançada, proporcionando a ampliação das possibilidades para uma produção mais sustentável.

Parcelamento de fontes alternativas de nitrogênio no milho safrinha em sucessão à soja

Increasing out-of-season corn productivity is possible by the application of nitrogen fertilizers even when in succession to soybean. On the other hand, information concerning the best sources of nitrogen and ways of splitting the doses to be applied is still scarce. Having that in mind, an experiment was carried out viewing to evaluate the effects of sources of nitrogen and ways of splitting doses of those N fertilizers on out-of-season corn sown in succession to soybean cultivated in a no-tillage system. The experiment took place in Chapadão do Céu, state of Goiás, Brasil (latitude of 18°35’42’’ South, longitude of 52°47’59’’ West and mean altitude above sea level of 802 m) in an Acrutox. The experimental units were distributed in the field in accordance with a randomized complete block design, in a factorial scheme 3 X 5 + 1, with four replications. Three were the sources of N: urea, urea extruded with starch (Amireia®) and ammonium sulfonitrate with a nitrification inhibitor (Entec®) and five the ways of splitting the nitrogen dose : 90-0, 60-30, 45-45, 30-60, and 0-90 in which the first fraction was applied at sowing and the second in side dressing. In addition to those, there was a check treatment, without N. All plots received, at sowing, 12 kg ha-1 of N by the mixture NPK. The ways of splitting the N dose and the sources of N had no significant effect on the levels of N and S in the leaves, first ear height, the final plant population, the number of ears per plant, and the number of grains per ear. N in the Entec® form at the highest doses applied in side dressing resulted in the highest grain yield, independently of the way the N dose was split. Only in the form Entec® the dose of 90 kg ha-1 of N increased grain productivity by 9.6% in comparison with the check treatment.

Avaliação in vitro da eficácia de extratos de plantas medicinais do Cerrado frente Staphylococcus aureos isolado de difetentes fontes de propriedades leiteiras

The objective of this study is to evaluate the potencial microbial activity in-vitro from the extract of some endemic plants from Cerrado such as Baccharis dracunculifolia, Cochlospermum regium, Croton antisyphiliticus, Eugenia dysenterica and Lippia sidoides, against the agent Staphylococcus aureus isolated from bovine mastitic milk, osteo from cow’s teat, milker equipament, nasal cavitites and milker’s gullet. The extracts were prepared from aerial parts as well as the reticular systems of plants using the solvents methanol, hexane and chloroform at a concentration of 10%. To evaluate the antimicrobial activity, the technique of microdilution in broth was used for determining the Minimal Inibitory Concentration (MIC) followed by the determination of Minimal Bactericidal Concentration (MBC). The extracts from Baccharis dracunculifolia and Croton antisyphiliticus, followed by extracts from Lippia sidoides, reported respectively, presented better inhibitory activity against the multiplication of the bacteria Staphylococcus aureus. Furthermore, the results demonstrate that the isolated strains from the milk and nasal cavities of the milker showed strong resistance against gentamicin, active agent commonly applied to combat mastitis bovine. However, there was sensitivity against extracts from the reported plants, reinforcing the importance of the medicinal plants as a therapeutic resource and its aplicability.