The bedding material used in barns for dairy cows has a significant effect on animal welfare and performance. Bedding influences the duration in which animals remain lying down and, consequently, the processes of rumination and milk production. It is crucial to have a complete understanding of the properties of bedding materials and the effects of alternative bedding materials on dairy cattle. This paper aims to evaluate the physical, chemical, and biological properties of various alternative and conventional bedding materials for dairy cattle for use in compost bedded pack or freestall barn systems. We analyzed 50 samples of 17 bedding materials produced in 3 European countries. We analyzed physical properties including the water holding capacity, porosity, moisture content, bulk density, dry bulk density, and particle size. Chemical analyses were performed to determine the total N, total organic C, and C:N ratio. In the biological analyses, the Escherichia coli count, total bacteria count, coliform count, and Klebsiella spp. count were assessed. The results demonstrated how the physical properties of the bedding materials may influence the chemical and biological properties. All of the materials presented adequate chemical properties to be used as bedding material. The physical properties of the bedding materials differed widely among the materials except for the dry bulk density, which presented no difference. Moreover, the contamination of each studied microorganism was observed for each bedding material to determine which material had the lowest level of contamination. Posidonia oceanica, Miscanthus grass, and spelt husks could be considered as a potential alternative material for use as bedding material for dairy cows in both systems (i.e., composted bedded pack and freestall). This ex-periment illustrated the importance of performing thorough physical, chemical, and biological analyses before implementing a material as bedding for dairy cattle.

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Neuroglia interactions are essential for the nervous system and in the retina Müller cells interact with most of the neurons in a symbiotic manner. Glutathione (GSH) is a low-molecular weight compound that undertakes major antioxidant roles in neurons and glia, however, whether this compound could act as a signaling molecule in neurons and/or glia is currently unknown. Here we used embryonic avian retina to obtain mixed retinal cells or purified Müller glia cells in culture to evaluate calcium shifts induced by GSH. A dose response curve (0.1–10mM) showed that 5–10mM GSH, induced calcium shifts exclusively in glial cells (later labeled and identified as 2M6 positive cells), while neurons responded to 50mM KCl (labeled as βIII tubulin positive cells). BBG 100nM, a P2X7 blocker, inhibited the effects of GSH on Müller glia. However, addition of DNQX 70μM and MK-801 20μM, non-NMDA and NMDA blockers, had no effect on GSH calcium induced shift. Oxidized glutathione (GSSG) at 5mM failed to induce calcium mobilization in glia cells, indicating that the antioxidant and/or structural features of GSH are essential to promote elevations in cytoplasmic calcium levels. Indeed, a short GSH pulse (60s) protects Müller glia from oxidative damage after 30 min of incubation with 0.1% H2O2. Finally, GSH induced GABA release from chick embryonic retina, mixed neuron-glia or from Müller cell cultures, which were inhibited by BBG or in the absence of sodium. GSH also induced propidium iodide uptake in Müller cells in culture in a P2X7 receptor dependent manner. Our data suggest that GSH, in addition to antioxidant effects, could act signaling calcium shifts at the millimolar range particularly in Müller glia, and could regulate the release of GABA, with additional protective effects on retinal neuron-glial circuit.

Avicultura de corte. Conforto ambiental. ADDITIONAL KEYWORDS Broiler. Environmental confort. RESUMOO objetivo desta revisão foi de discutir a utilização da lógica fuzzy na análise das variáveis que afetam a ambiência de frangos de corte e exemplificar situações bem sucedidas de utilização dessa metodologia na predição das variáveis que afetam o conforto térmico para frangos de corte, além de apresentar a potencialidade dessa metodologia que pode ser usada como suporte à tomada de decisão sobre o controle da climatização dos galpões avícolas, garantindo, assim, melhorias na produção. Dentre as variáveis analisadas por meio da lógica fuzzy, destaca-se o controle da temperatura, umidade relativa, luminosidade, poluentes aéreos e concentração de alguns gases. Esses fatores influenciam diretamente a condição de conforto e bem-estar das aves, afetando sua produtividade. Portanto, é de grande importância uma ferramenta que pode contribuir na tomada de decisão, possibilitando, o controle do ambiente térmico no interior de galpões para produção de frangos. SUMMARYThe aim of this review was to discuss the use of fuzzy logic to analyze variables that affect the environment of broiler chickens, to give some examples of successful use of this metodology to predict the variables that affect the thermal comfort for chickens, and to show the potential of this methodology that can be used to support decisions on the climate control in broiler houses, thus ensuring improvements in production. Among the variables analyzed using the fuzzy logic, we highlight the temperature and moisture control inside of broiler houses, light, air pollutants and concentration of some gases. These factors have a direct influence in the comfort condition and welfare of birds, so they affect broiler productivity. Therefore, it is very important when a tool comes to contribute on taking decisions. The fuzzy logic allows the control of thermal environment inside of barns for broilers´ production. INTRODUÇÃOO sistema produtivo avícola tem investido cada vez mais em ferramentas que possam otimizar a produtividade de frangos de corte. Frente às atuais demandas existentes, há uma busca incansável por conhecimento dos parâmetros que afetam essa atividade para que se obtenha a máxima produtividade de carne com o menor custo. Diversos estudos apontam para a interferência que o ambiente de criação exerce sobre a produtividade animal (Moura et al., 2006;Salgado et al., 2007;Nazareno et al., 2009). Nesse sentido, sabe-se que o

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Este trabalho teve como objetivo identificar se variáveis climatológicas e de umidade do solo estão relacionadas com a variação da força de desprendimento dos frutos do cafeeiro (Coffea<em> arabica </em>L<em>.</em>) ao longo do período de maturação. O trabalho foi desenvolvido no Departamento de Agricultura da Universidade Federal de Lavras (UFLA) buscando analisar o comportamento da força de desprendimento dos frutos do cafeeiro nas maturações verde e cereja ao longo do período de maturação mediante as variáveis meteorológicas do ar e de umidade do solo, conduzindo os ensaios sob quatro diferentes condicionamentos de umidade do solo. As alterações nos parâmetros meteorológicos e de umidade do solo acarretam na alteração da força de desprendimento dos frutos, principalmente na maturação verde. Com o aumento de temperatura ocorreu diminuição da força de desprendimento dos frutos verdes e tendência de diminuição para os frutos cereja. A umidade do solo apresentou correlação positiva com a força de desprendimento dos frutos verdes e tendência positiva para os frutos cereja. A precipitação tendeu a diminuir a força de desprendimento dos frutos verde e cereja nos três dias após sua ocorrência.

The objective of this study was to evaluate the potential of the practical application of unmanned aerial vehicles and RGB vegetation indices (VIs) in the monitoring of a coffee crop. The study was conducted in an experimental coffee field over a 12-month period. An RGB digital camera coupled to a UAV was used. Nine VIs were evaluated in this study. These VIs were subjected to a Pearson correlation analysis with the leaf area index (LAI), and subsequently, the VIs with higher R2 values were selected. The LAI was estimated by plant height and crown diameter values obtained by imaging, which were correlated with these values measured in the field. Among the VIs evaluated, MPRI (0.31) and GLI (0.41) presented greater correlation with LAI; however, the correlation was weak. Thematic maps of VIs in the evaluated period showed variability present in the crop. The evolution of weeds in the planting rows was noticeable with both VIs, which can help managers to make the decision to start crop management, thus saving resources. The results show that the use of low-cost UAVs and RGB cameras has potential for monitoring the coffee production cycle, providing producers with information in a more accurate, quick and simple way.

RESUMO:A agricultura de precisão surge como uma importante ferramenta para maximizar o gerenciamento da atividade cafeeira, principalmente para esta cultura, que possui elevado custo de produção. O presente trabalho teve por objetivo fazer um estudo comparativo da viabilidade econômica de dois sistemas de adubação na lavoura cafeeira: o sistema utilizando as técnicas da agricultura de precisão e o sistema de aplicação convencional. Os dados utilizados foram extraídos dos custos de produção da fazenda Brejão, no sul de Minas Gerais, em três áreas (22 ha, 10,52 ha e 6,23 ha), onde foram realizadas aplicações de adubos de forma diferenciada nas safras de 2007/2008 e 2008/2009. O sistema de adubação em agricultura de precisão caracterizou-se por coleta de amostras de solo, georreferenciadas, e aplicação diferenciada de fósforo e potássio. Os custos da adubação convencional foram obtidos por meio de simulações, considerando a amostragem convencional do solo realizada nas glebas. Para efeito comparativo entre os sistemas de adubação, foram consideradas as operações e as quantidades de adubos necessárias em cada sistema. Entre os dois sistemas, observou-se diferenças de aplicação dos elementos fósforo e potássio, e também nas quantidades aplicadas. A adubação diferenciada foi vantajosa para as áreas de 22 ha e 10,52 ha, nas duas safras em estudo, e para a área de 6,23 ha só foi vantajosa (menor prejuízo) na safra de 2008/09. PALAVRAS-CHAVE:adubação a taxas variáveis, agricultura de precisão, custos, viabilidade, cafeicultura, adubação convencional. ECONOMIC VIABILITY OF THE VARIABLE RATE TECHNOLOGY COMPARED TO THE TRADITIONAL SYSTEM OF FERTILIZATION IN A COFFEE FIELD: A CASE STUDY ABSTRACT:The precision agriculture appears as an important tool to improve coffee field management, mainly to this culture that has high production costs. The present work intended to accomplish a comparative study of the economic feasibility of two fertilizer systems: one using the precision agriculture and other using conventional fertilization. The data base used were extracted from the production costs of the Brejão farm, in south of Minas Gerais, in three areas (22 ha, 10.52 ha and 6.23 ha), where were applied fertilizer in variable rates in the 2007/2008 and 2008/2009 harvests. The precision agriculture was characterized by the georeferenced soil sampling and the application of phosphorus and potassium in variable rates. The conventional fertilization costs were obtained by simulations considering the traditional soil sampling performed at these areas. In order to compare the two fertilization systems, it was considered the operations and the amount of fertilizer necessary in each of the fertilization system. It was realized differences in the elements and in the amount that should be applied between the two systems. The variable rate fertilization was more profitable to the area of 22 ha and 10.52 ha in the two harvests studied and to the area of 6.23 ha was profitable (less prejudice) only to the last crop.