Efeito da suplementação com fitase sobre o desempenho e digestibilidade de nutrientes para frangos de corte

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Los ferrocarriles transandinos: la interrupción de los servicios y su posible reanudación

Construir la infraestructura y luego operar un ferrocarril que parta desde la costa del Pacífico de Sudamérica y que, a pocas decenas de kilómetros al interior, deba escalar los cerca de 4 000 metros sobre el nivel del mar por la Cordillera de los Andes, siempre ha presentado desafíos, tanto para los ingenieros civiles responsables de la construcción de las vías, como para los gerentes encargados de la operación de los trenes.A mediados de 2001, debido a la adversidad climática de los últimos tiempos, se encuentran paralizados los servicios de dos de los cuatro ferrocarriles transandinos que funcionaban hace veinte años, y un tercero se encuentra inoperante, por problemas institucionales. Sin embargo, dos de los tres ferrocarriles actualmente desactivados podrían volver a prestar servicios en el corto plazo y, además, es dable vislumbrar la construcción de un nuevo ferrocarril transandino, que cruzaría la Cordillera de los Andes más al sur del Continente, a una altitud inferior a 1 750 metros sobre el nivel del mar.

Transandean railroads: the interruption of service and prospects for resumption

Building the infrastructure and then operating a railroad which starts on the Pacific coast of South America and which, a few score kilometres inland, must climb close to 4,000 metres above sea level in the Andes mountains has always presented challenges both for the civil engineers responsible for its construction and for the managers in charge of its operation.As at mid-2001, two of the four transandean railroads that ran 20 years ago are out of service, owing to adverse weather conditions, and a third is not operating as a result of institutional problems.Nevertheless, two of the three railroads that are now shut down could resume service soon. Furthermore, there is a possibility that a new transandean railroad could be built that would cross the Andes mountains further south, at an altitude of less than 1,750 meters.

Controle químico de nematoides em canaviais implantados com Tecnologia Plene

Pós-graduação em Agronomia (Produção Vegetal) - FCAV

Curvas de progresso de doenças foliares do milho, sob diferentes tratamentos fungicidas

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Biologia e comportamento de Diachasmimorpha longicaudata Ashmead (Hymenoptera: Braconidae) criado sobre larvas de Ceratitis capitata Wiedemann (Diptera: Tephritidae) irradiadas e não irradiadas com radiação gama

Pós-graduação em Agronomia (Proteção de Plantas) - FCA

Estabilidade da fitase e sua utilização na alimentação de frangos de corte

This work was designed to evaluate the effect of storage forms and conditions upon the enzyme activity of phytase and bioavaibility of calcium and phosphorus in broiler diets. The work was accomplished in two steps. The first step, made in the laboratory measured the activity of the phytase enzyme along the storage period. In this step, two experiments were performed: Experiment 1, constituted of 5 treatments (pure phytase stored at 0 °C, 4 °C and environmental temperature and mixed to vitamin and mineral supplement, stored at environmental temperature) in CRD and split plot scheme. The activities were evaluated every 14 days for 112 days of storage, being verified that the phytase storage in the pure form at 0o C was superior to the other treatments. Experiment 2, made up of 4 treatments (phytase mixed to the ration directly, directly and afterwards pelleted, via mineral supplement and via vitamin supplement),all the treatments being stored at environmental temperature, in CRD and split plot scheme. The activities were evaluated every 7 days for 56 days' storage, being verified that the storage of the phytase mixed to the ration via vitamin supplement and directly with the ration pelleted later, provoked a fall in phytase activity when compared with the other treatments. In the second step, the effect of phytase on the bioavaibility of calcium and phytic phosphorus was evaluated, 2 experiments being accomplished (3 and 4); in both experiments were utilized 576 broiler line chicks, housed in an array of heated batteries, receiving practical diets on the basis of corn and soybean meal (basal) for 21days. At the end of 27 days of age,96 birds were slaughtered for evaluation of the mineral contents (Ca and P) in the tíbias and plasma phosphorus. The excretae were collected from 22 to 27 days of age of the birds. Experiment 3: A CRD with the treatments in 2 x 3 x 2 +4 factorial arrangement was utilized, namely, two levels of total phosphorus (0.35 and 0.45% of total phosphorus), three leveis of phytase (500, 750 and 1,000 FTU) and four additional treatments with levels of 0.35 and 0.45 % of available phosphorus for each sex, with three replicates per treatment. There was significant interaction among levels of phosphorus and phytase (P< 0.05) for weight gain, ration consumption and feed conversion. Phytase did not indicate significant differences when the level 0.45% was utilized, nevertheless, at the level 0.35% as phytase was supplemented, weight gain, ration consumption and feed conversion were improved, chiefly with 1,000 FTU/Kg, in both sexes. The males presented greater weight gain. The ration consumption and feed conversion were equal to those of females. The contrast 0.45% did not affect the performance of males and females, the same not occurring with the level 0.35%,at which the available phosphorus was superior in both the sexes. The highest contents of ashes, phosphorus and calcium in the tíbias and plasma phosphorus were obtained with the levels of 750 and 1,000 FTU/Kg of phytase and 0.45% of total phosphorus. The males presented higher contents of ashes in the tibias. The level 0.45% of available phosphorus presented the greatest contents of ashes, calcium and phosphorus in the tibias, and phosphorus in the plasma. The lowest excretions of phosphorus occurred at the levels 0.35% of total phosphorus and 1,000FTU/kg of phytase. The lowest contents of ashes and calcium in the excretae were obtained with 0.35% and 1,000FTU/Kg of phytase. The females excreted smallest amounts of ashes, calcium and phosphorus than the males. Experiment 4: a CRD with the treatments in 3 x 4 x 2 factorial arrangement, namely, three levels of phytase (0, 500 and 1,000 FTU), four levels of calcium (0.7, 0.8, 0.9 and 1.0%) with four replicates per treatment. The performance was not affected by the treatments utilized, the males being superior to the females in weight gain, feed consumption and conversion. The contents of ashes in the tibias were not affected by the levels of phytase but as calcium levels raised, the ash contents increased. The contents of calcium and phosphorus in the tibias increased with the supplementation of 500 and 1,000 FTU/kg of phytase and with calcium levels. The utilization of phytase did not decrease the excretion of ashes, calcium and phosphorus.

Nanopartículas de óxido de ítrio dopado com Eu3+ contendo prata

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Desenvolvimento e validação de método de análise por cromatografia gasosa para metabólitos polares de folhas de cana-de-açúcar e aplicação na avaliação da influência do teor de 'CO IND. 2' atmosférico na composição de metabólitos polares de cana-de-açucar

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito do tratamento com GnRH ou hCG no dia 5 pós inseminação artificial sobre a concentração sérica de progesterona e a taxa de concepção em vacas holandesas lactantes durante o verão

Pós-graduação em Medicina Veterinária - FMVZ

Propagação vegetativa de Tamarindus indica L

Pós-graduação em Agronomia - FEIS

Valor nutritivo, pela Tilápia do Nilo, do farelo de algodão suplementado com fitase

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Exigências de lisina e de metionina+cistina digestíveis para aves de corte da linhagem ISA Label em sistemas semi-confinado

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeito da inclusão da fitase sobre o desempenho, densitometria óssea, excreção de fósforo e nitrogênio e viabilidade econômica de frangos de corte

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Propriedade antifúngica de resina para base de prótese modificada com nanopartículas de prata

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)