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Efecto de la adición de minerales en agua o en alimento sobre variables productivas y fisiológicas en pollos de engorde bajo estrés calórico Texte intégral
2010
Farfán, Charly(Universidad Central de Venezuela Facultad de Agronomía Instituto de Producción Animal) | Oliveros, Yngrid(INIA CENIAP) | De Basilio, Vasco(Universidad Central de Venezuela Facultad de Agronomía Instituto de Producción Animal)
A través de un experimento con 192 pollos mantenidos a 30°C en promedio de temperatura ambiente (TA) entre 28 días y 35 días, se evaluó el efecto de la adición de minerales en el agua o el alimento sobre las variables productivas y fisiológicas durante la etapa de finalización, bajo condiciones de estrés calórico crónico y agudo en pollos de engorde. Luego se simuló a los 36 días de edad, el estrés agudo con 36 °C/6 horas, incluyendo 3 tratamientos: T1= Alimento balanceado sin adición mineral, T2= Alimento balanceado con adición mineral en alimento y T3= Alimento balanceado con adición mineral en agua. El diseño experimental fue un arreglo completamente al azar, con 8 repeticiones/tratamiento, 8 pollos/repetición. La composición del suplemento mineral fue: NaHCO3 (0,83%); NH4Cl (0,07%) y; NaCl (0,30%), obteniéndose un balance de electrólitos de 240 mEq. Se evaluaron, el consumo de alimento, consumo de agua, ganancia de peso, conversión de alimento, temperatura corporal (TC), nivel de hiperventilación (NH), durante el estrés crónico y mortalidad (M) durante el estrés agudo. Los datos fueron analizados mediante pruebas de ANAVAR y de Chicuadrado para la mortalidad. Encontrándose que al adicionar minerales tanto en el agua como en el alimento, no hubo efecto significativo en las variables productivas. Se observó que los pollos que recibieron minerales (T2 y T3), incrementaron el consumo promedio de agua en un 34% (P=0,016) con respecto al T1. La adición de minerales en el agua permitió una disminución (P=0,007) de la TC (42,80 ± 0,16 °C), NH (159,95 ± 4,93 insp/min) y una reducción de la M hasta un 22% durante la simulación del estrés calórico agudo. Se concluye que la adición de minerales afecta principalmente las variables fisiológicas y la mortalidad | In order to evaluate the effect of mineral supplying in water or feed on productive and physiological variables in broilers under acute and chronic heat stress during final growth stage an experiment was conducted. Using a completely randomized design, a total of 195 broilers were randomly assigned to three treatments with 8 replicates of 8 birds each one. The treatments were T1 = basal diet with no mineral addition; T2 = basal diet plus mineral addition in feed; T3 = basal diet plus mineral addition in water, which were applied from 28 days of age. Before this period all broilers were receiving a same balance diet. The composition of the mineral formula used was: NaHCO3 (0,83%); NH4Cl (0,07%); NaCl (0,30%), obtaining an electrolytes balance of 240 mEq. Between 28 to 35 days of age, all these groups of birds were subjected at 30 ºC and the following day an acute heat stress was simulated using 36ºC for 6 hours. At 28 to 36 days old the following parameters were measured: feed and water consumption, body weight gain, feed conversion index, body temperature (BT), hyperventilation level (HL) and mortality (M) during acute stress. An ANOVA test was applied to all variables except M, which a Chi-squared test was performed. No significant effects on productive variables were found with minerals adding, neither to the water nor to the feed. Water consumption was 34% greater in T3 and T2 (P=0,016) regard to T1, which not received minerals. Mineral addition in water reduced significantly (P=0,007) BT (42,80 ± 0,16 °C), HL (159,95 ± 4,93 breaths/min) and M was reduced until 22% during acute heat stress period. It is concluded that mineral supplying affects mostly physiological variables and mortality
Afficher plus [+] Moins [-]A Holistic View of Global Croplands and Their Water Use for Ensuring Global Food Security in the 21st Century through Advanced Remote Sensing and Non-remote Sensing Approaches Texte intégral
2010
Prasad S. Thenkabail | Munir A. Hanjra | Venkateswarlu Dheeravath | Muralikrishna Gumma
A Holistic View of Global Croplands and Their Water Use for Ensuring Global Food Security in the 21st Century through Advanced Remote Sensing and Non-remote Sensing Approaches Texte intégral
2010
Prasad S. Thenkabail | Munir A. Hanjra | Venkateswarlu Dheeravath | Muralikrishna Gumma
This paper presents an exhaustive review of global croplands and their water use, for the end of last millennium, mapped using remote sensing and non-remote sensing approaches by world’s leading researchers on the subject. A comparison at country scale of global cropland area estimated by these studies had a high R2-value of 0.89–0.94. The global cropland area estimates amongst different studies are quite close and range between 1.47–1.53 billion hectares. However, significant uncertainties exist in determining irrigated areas which, globally, consume nearly 80% of all human water use. The estimates show that the total water use by global croplands varies between 6,685 to 7,500 km3 yr−1 and of this around 4,586 km3 yr−1 is by rainfed croplands (green water use) and the rest by irrigated croplands (blue water use). Irrigated areas use about 2,099 km3 yr−1 (1,180 km3 yr−1 of blue water and the rest from rain that falls over irrigated croplands). However, 1.6 to 2.5 times the blue water required by irrigated croplands is actually withdrawn from reservoirs or pumping of ground water, suggesting an irrigation efficiency of only between 40–62 percent. The weaknesses, trends, and future directions to precisely estimate the global croplands are examined. Finally, the paper links global croplands and their water use to a paradigm for ensuring future food security.
Afficher plus [+] Moins [-]A Holistic View of Global Croplands and Their Water Use for Ensuring Global Food Security in the 21st Century through Advanced Remote Sensing and Non-remote Sensing Approaches Texte intégral
2010
Thenkabail, P S | Hanjra, M A | Dheeravath, V | Gumma, M K
This paper presents an exhaustive review of global croplands and their water use, for the end of last millennium, mapped using remote sensing and non-remote sensing approaches by world’s leading researchers on the subject. A comparison at country scale of global cropland area estimated by these studies had a high R2-value of 0.89–0.94. The global cropland area estimates amongst different studies are quite close and range between 1.47–1.53 billion hectares. However, significant uncertainties exist in determining irrigated areas which, globally, consume nearly 80% of all human water use. The estimates show that the total water use by global croplands varies between 6,685 to 7,500 km3 yr−1 and of this around 4,586 km3 yr−1 is by rainfed croplands (green water use) and the rest by irrigated croplands (blue water use). Irrigated areas use about 2,099 km3 yr−1 (1,180 km3 yr−1 of blue water and the rest from rain that falls over irrigated croplands). However, 1.6 to 2.5 times the blue water required by irrigated croplands is actually withdrawn from reservoirs or pumping of ground water, suggesting an irrigation efficiency of only between 40–62 percent. The weaknesses, trends, and future directions to precisely estimate the global croplands are examined. Finally, the paper links global croplands and their water use to a paradigm for ensuring future food security.
Afficher plus [+] Moins [-]Evaluación de la suplementación en el agua y alimento de un complejo enzimático y un complejo de aminoácidos en el engorde de pollos broiler Texte intégral
2010
Cueva Pinzón, Manuel Augusto | Galo Escudero Sánchez
El presente trabajo investigativo titulado "EVALUACIÓN DE LA SUPLEMENTACIÓN EN EL AGUA Y ALIMENTO DE UN COMPLEJO ENZIMÁTICO Y UN COMPLEJO DE AMINOÁCIDOS EN EL ENGORDE DE POLLOS BROILERS", se lo realizó en la ciudad de Loja, en el barrio La Manda., durante los meses de enero a marzo del 2010. Los objetivos fueron: Evaluar el efecto de la suplementación en el alimento de un complejo enzimático frente a un complejo de aminoácidos en el agua de bebida, en el engorde de pollos broiler y determinar el incremento de peso y conversión alimenticia en los grupos experimentales y conocer la rentabilidad económica al adicionar el complejo enzimático y de aminoácidos en el crecimiento y engorde. Para la realización de este trabajo experimental se utilizaron 240 pollos broiler de un día de edad, se conformó tres tratamientos con cuatro repeticiones cada uno. El tratamiento uno correspondió a la aplicación en el alimento balanceado la cantidad de 125 g de PoultIygrow 250 por tonelada de alimento suministrado durante el 1 hasta los 28 días de edad y del 29 a los 49 días se dio alimento sin enzimas; el tratamiento dos que correspondió en administrar en el agua POUVIT AMINOÁCIDOS LIQUIDO en la cantidad de 1 cc por cada litro de agua de bebida que fue suministrada desde el 29 hasta los 49 días de edad, mientras tanto que desde el 1 a los 28 días de edad se dio solo agua; el tratamiento treses el que se le asignó al grupo testigo que consiste en administrarles alimento y agua sin enzimas ni aminoácidos. Se utilizó el diseño de bloques al azar, con tres tratamientos y cuatro repeticiones. Las variables en estudio fueron: incremento de peso, consumo de alimento, conversión alimenticia, mortalidad y rentabilidad. Los resultados obtenidos fueron: El mayor peso promedio semanal lo obtuvo el tratamiento uno, que corresponde a la aplicación dePoultIygrow 250 con2064.53 gramos. En incremento de peso, el mejor resultó ser el tratamiento uno que corresponde a la aplicación del complejo enzimático desde el primer día hasta los 28 días con 336,9 gramos. El mayor consumo de alimento, lo obtuvo el tratamiento tres sin aditivo, con 4109.15 gramos por semana, seguido del tratamiento dos que corresponde a la aplicación del POUVIT AMINOACIDOS desde el primer día hasta los 28 días, con 4133.1 gramos de consumo promedio. La mejor conversión alimenticia la presentó el tratamiento uno con 1.86, seguido del tratamiento tres con 1.89, luego del tratamiento dos con 1.94, y finalmente el tratamiento cuatro sin acidificante con 1.99. El promedio de mortalidad que se registró durante todo el desarrollo del trabajo fue del 2.08. La mejor rentabilidad como se puede notar el tratamiento uno generó mayores ganancias, con una rentabilidad del 16.42%.
Afficher plus [+] Moins [-]Inhibitory effect of Eucalyptus sp. essential oil, pure and in associated to antibiotics, against strains of Escherichia coli and Staphylococcus aureus isolated from handlers, food, sand and seawater | Efeito inibitório do óleo essencial do Eucalyptus sp., puro e associado a antibióticos, frente a cepas de Escherichia coli e Staphylococcus aureus isoladas de manipuladores, alimentos, areia e água do mar
2010
Nascimento, A.R. | Serra, J.L. | Martins, A.G.L. de A. | Filho, J.E.M. | Aragão, N.E. | Andrade, L.S.
The role of the introduced amphipod Gmelinoides fasciatus and native amphipods as fish food in two large-scale north-western Russian inland water bodies: Lake Ladoga and Rybinsk Reservoir Texte intégral
2010
Berezina, N.A. | Strelnikova, A.P.
This paper focuses on the role of invasive, omnivorous/carnivorous amphipods in the food web of lakes and evaluates their significance as food items for fishes in two major lakes and reservoirs of the northwestern region of Russia: Lake Ladoga and Rybinsk Reservoir. Fish samples from both water bodies were collected, there age determined and their stomach content analysed to assess the role of the introduced amphipod in the diet. Fish species mainly analysed were: perch Perca fluviatilis, ruffe Gymnocephalus cernuus, burbot Lota lota, roach Rutilus rutilus, vendace Coregonus albula and kilka Clupeonella cultriventris. Analysis of original and literature data showed that the energy flow from zoobenthos to fish was modified by the Baikalian amphipod Gmelinoides fasciatus, introduced in the 1960s-80s into many lakes and reservoirs of Russia. The invader established successfully in different aquatic systems, rapidly reaching high abundances. Examples from Lake Ladoga and the Rybinsk Reservoir confirmed that the species is an important food item for littoral benthivorous fishes (ruffe, perch, gobies, burbot), especially at early ontogenetic stages and also for several pelagic fish (vendace, kilka). Although these fish species are considered low food quality, they enrich the food supply for large predatory fish species. In Lake Ladoga, G. fasciatus influenced negatively the abundance and biomass of native benthic invertebrates (including Gammarus lacustris and Asellus aquaticus) which were previously important prey items for littoral fishes: in the beginning of introduction up to 24100 m⁻² and 33.5 g m⁻²; after introduction 6200-7800 m⁻² and 16.5 g m⁻², respectively. At the same time, the invader uses food sources (chironomids and oligochaetes) that would otherwise not be available to fishes. Therefore, the introduction of G. fasciatus into lakes and reservoirs of European part of Russia led to a greater share of the benthic productivity available to fishes, thereby allowing the intensive use of new ecosystem components and increasing the overall production in these systems.
Afficher plus [+] Moins [-]Tetrahydrofuran-water extraction, in-line clean-up and selective liquid chromatography/tandem mass spectrometry for the quantitation of perfluorinated compounds in food at the low picogram per gram level Texte intégral
2010
Ballesteros-Gómez, Ana | Rubio, Soledad | van Leeuwen, Stefan
A new solvent extraction system was developed for extraction of PFCs from food. The extraction is carried out with 75:25 (v/v) tetrahydrofuran:water, a solvent mixture that provides an appropriate balance of hydrogen bonding, dispersion and dipole-dipole interactions to efficiently extract PFCs with chains containing 4-14 carbon atoms from foods. This mixture provided recoveries above 85% from foods including vegetables, fruits, fish, meat and bread; and above 75% from cheese. Clean-up with a weak anion exchange resin and Envi-carb SPE, which were coupled in line for simplicity, was found to minimize matrix effects (viz. enhancement or suppression of electrospray ionization). The target analytes (PFCs) were resolved on a perfluorooctyl phase column that proved effective in separating mass interferences for perfluorooctane sulfonate (PFOS) in fish and meat samples. The mass spectrometer was operated in the negative electrospray ionization mode and used to record two transitions per analyte and one per mass-labeled method internal standard. The target PFCs were quantified from solvent based calibration curves. The limits of detection (LODs) were as low as 1-5pganalyteg⁻¹ food; by exception, those for C₄ and C₅ PFCs were somewhat higher (25-30pgg⁻¹) owing to their less favourable mass response. To the best of our knowledge these are among the best LODs for PFCs in foods reported to date. The analysis of a variety of foods revealed contamination with PFCs at levels from 4.5 to 75pgg⁻¹ in 25% of samples (fish and packaged spinach). C₁₀-C₁₄ PFCs were found in fish, which testifies to the need to control long-chain PFCs in this type of food. The proposed method is a useful tool for the development of a large-scale database for the presence of PFCs in foods.
Afficher plus [+] Moins [-]Soil and water resources components of "Conservation agriculture production systems for food security in Cambodia and the Philippines". USAID-SANREM-CRSP Project "Cambodian sub-component". Annual Report (April to September 2010) Texte intégral
2010
Boulakia, Stéphane | Chabierski, Stéphane | Veng, Sar | Lyda, Hok
This report briefly introduces the research and development activities implemented in this first year of operations by the Cambodian team of the SANREM-CRSP. The PADAC team and its local SANREM partners, the NGO AVSF-CICDA (Agronomes et Vétérinaires sans frontière) and the faculty of agronomy of the Royal University of Agriculture have mainly implemented the following actions in the 2 chosen villages of Rattanak Mundul district (Battambang province, west Cambodia): - Initiation of pilot farm extension network for DMC adoption (36 ha with 25 families) combined with farmers organization development - Implementation of the double (DMC vs Plow) plots sub-sample for soil's parameter evolution with T0 soil sampling - Farming systems characterization through a 6 months surveys carried out by 2 master students, supported by CIRAD scientists; requested database for the coming implementation of a Reference Farm Network - Several fields visit to introduce DMC to local farmers (progressive extension of the network) and other stakeholders.(résumé d'auteur)
Afficher plus [+] Moins [-]Tratamiento del condensado vegetal de los concentradores de jugos en frutos de cítricos después de la cosecha con el fin de poder utilizarlo como agua de alimentación de calderas Texte intégral
2010
Roque Chávez, Alexander(Especialista B en beneficio y producción agropecuaria Empresa de Cítricos Héroes de Girón, Jagüey Grande) | Jiménez Armelo, Yosbel(Universidad Agraria de La Habana Facultad de Ciencias Técnicas)
El trabajo se desarrolla con el objetivo de determinar el valor del pH del condensado vegetal obtenido de los concentradores de jugos, su variación en dependencia con el tipo de cítrico y su madures, así como determinar la cantidad de hidróxido de sodio (NaOH) necesario para su tratamiento con el fin de poder utilizarlo como agua de alimentación de calderas, para el estudio se tomaron varias muestras de pH durante la campaña 2008-2009 que abarcaron siete meses, los valores de pH se compararon con el Ratio de la fruta, obteniéndose una correlación de 0,00149, demostrándose mediante métodos estadísticos que el pH del condensado vegetal es constante durante toda la campaña y que es posible utilizarlo como agua de alimentación de calderas, adicionándole a cada metro cúbico 10, 17 g de hidróxido de sodio logrando elevar su pH de 4 hasta 8. | The objective of this paper is to determine the value of the pH on the condensed vegetable obtained from the juice concentrators, its variance depending on the kind of citrus fruits and its maturity as well as to determine the amount of sodium hydroxide needed for its treatment, to be used to feed the boilers. For this study many samples of pH were taken during the campaign 2008-2009, in a 7 month period. The values of pH were compared to the fruit ratio obtaining a correlation of 0,00149, and by statistics methods it is found that the condensed vegetable pH is constant during the hole campaign and that it is possible to use it to feed the boilers adding to every cubic meter 10,17 g of sodium hydroxide to increase values of pH, from 4 to 8.
Afficher plus [+] Moins [-]Tratamiento del condensado vegetal de los concentradores de jugos en frutos de cítricos después de la cosecha con el fin de poder utilizarlo como agua de alimentación de calderas Texte intégral
2010
Alexander Roque Chávez | Yosbel Jiménez Armelo
El trabajo se desarrolla con el objetivo de determinar el valor del pH del condensado vegetal obtenido de los concentradores de jugos, su variación en dependencia con el tipo de cítrico y su madures, así como determinar la cantidad de hidróxido de sodio (NaOH) necesario para su tratamiento con el fin de poder utilizarlo como agua de alimentación de calderas, para el estudio se tomaron varias muestras de pH durante la campaña 2008-2009 que abarcaron siete meses, los valores de pH se compararon con el Ratio de la fruta, obteniéndose una correlación de 0,00149, demostrándose mediante métodos estadísticos que el pH del condensado vegetal es constante durante toda la campaña y que es posible utilizarlo como agua de alimentación de calderas, adicionándole a cada metro cúbico 10, 17 g de hidróxido de sodio logrando elevar su pH de 4 hasta 8.
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