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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Intoxicações experimentais e naturais por Vicia villosa em coelhos e bovinos.

Sonne, Luciana January 2010 (has links)
Vicia villosa foi relacionada a intoxicações em bovinos e causa uma doença granulomatosa sistêmica caracterizada por lesões de pele e múltiplos nódulos esbranquiçados em vários órgãos. Nesse trabalho realizou-se a intoxicação experimental por sementes e folhas de V. villosa em coelhos e bovinos. Os coelhos que receberam 5g/kg de sementes de ervilhaca apresentaram lesões descamativas e crostosas nas orelhas e evidenciação dos tecidos linfóides do intestino. Os coelhos intoxicados por folhas de ervilhaca e que receberam a aplicação para o teste de hipersensibilidade apresentaram evidenciação dos tecidos linfoides do intestino que corresponderam na histologia a infiltrado de histiócitos, linfócitos e células gigantes multinucleadas. O bovino alimentado com sementes de ervilhaca (5g/kg) não apresentou a doença clínica. Na intoxicação experimental por folhas de V. villosa, o bovino não apresentou sinais clínicos, porém houve aumento nodular dos linfonodos que, na histologia, demonstravam infiltrado granulomatoso. Cinco casos de intoxicações naturais por V. villosa foram diagnosticados no Setor de Patologia Veterinária da Universidade Federal do Rio Grande do Sul (SPV-UFRGS) no período de 2005 a 2010. As principais alterações macroscópicas observadas foram lesões alopécicas e crostosas de pele e múltiplos nódulos branco-acinzentados principalmente localizados nos linfonodos, rins e coração. Na histologia dos animais intoxicados visualizava-se macrófagos, linfócitos, células epitelioides e células gigantes multinucleadas, plasmócitos e eosinófilos. A intensidade do infiltrado granulomatoso variou entre os cinco casos analisados e entre os órgãos de cada animal. Os testes imuno-histoquímicos caracterizaram os infiltrados, que foram constituídos principalmente por linfócitos T e macrófagos. Os resultados dos testes de hipersensibilidade cutânea em bovinos com extratos protéicos da planta sugerem que os animais com a doença clínica apresentam uma resposta de hipersensibilidade tardia enquanto que os demais animais modulam a resposta imune diferentemente. / Vicia villosa was associated with poisoning in cattle, causing a systemic granulomatous disease. Hairy vetch poisoning is characterized by skin lesions and multiple whitish nodules in several organs. This work reports experimental poisoning by seeds and leaves of V. villosa in rabbits and cattle and the spontaneous poisoning by V. villosa in cattle is described. Rabbits received 5g/kg of seeds of hairy vetch and presented scaly, crusted lesions in ear and enlargement lymphoid tissue of intestine. Rabbits poisoned by hairy vetch leaves that were tested for cutaneous hypersensitivity showed enlargement of intestine lymphoid tissue. The histologic feature of this, lesion consisted of granulomatous inflammation. Cattle fed with seeds of hairy vetch (5g/kg) did not have clinical disease. Experimental poisoning by leaves of V. villosa in cattle did not present clinical signs; however, nodules in lymph nodes were observed. Histologically, infiltration of macrophages, lymphocytes and multinucleated giant cells were observed. Five cases of poisoning by V. villosa in cattle were diagnosed at Setor de Patologia Veterinária of Universidade Federal do Rio Grande do Sul (SPV-UFRGS) in the 2005 to 2010 period. Gross lesions were alopecia, skin crusts and multiple nodules mainly located in lymph nodes, kidneys and heart. Microscopically, infiltration of lymphocytes, macrophages, multinucleated giant cells, plasma cells and eosinophils were observed. Intensity of granulomatous infiltration varied among the five cattle and between analyzed organs. The inflammatory infiltration was characterized by immunohistochemistry. It was mainly composed of lymphocytes T and macrophages. Cutaneous hypersensitivity tests with hairy vetch proteins suggest that cattle with clinic disease have type-IV hypersensitivity reaction while others show different immune response.
2

Untersuchungen über die Zusammensetzung des deutschen und amerikanischen Rotklees, der Zottelwicke und der Saatwicke während verschiedener Wachstumsstadien sowie über den Einfluss bestimmter Düngemittel auf die Zusammensetzung der Wicke /

Kuntze, Walther. January 1903 (has links)
Thesis (doctoral)--Universität Leipzig, 1903. / Lebenslauf. Includes bibliographical references.
3

Intoxicações experimentais e naturais por Vicia villosa em coelhos e bovinos.

Sonne, Luciana January 2010 (has links)
Vicia villosa foi relacionada a intoxicações em bovinos e causa uma doença granulomatosa sistêmica caracterizada por lesões de pele e múltiplos nódulos esbranquiçados em vários órgãos. Nesse trabalho realizou-se a intoxicação experimental por sementes e folhas de V. villosa em coelhos e bovinos. Os coelhos que receberam 5g/kg de sementes de ervilhaca apresentaram lesões descamativas e crostosas nas orelhas e evidenciação dos tecidos linfóides do intestino. Os coelhos intoxicados por folhas de ervilhaca e que receberam a aplicação para o teste de hipersensibilidade apresentaram evidenciação dos tecidos linfoides do intestino que corresponderam na histologia a infiltrado de histiócitos, linfócitos e células gigantes multinucleadas. O bovino alimentado com sementes de ervilhaca (5g/kg) não apresentou a doença clínica. Na intoxicação experimental por folhas de V. villosa, o bovino não apresentou sinais clínicos, porém houve aumento nodular dos linfonodos que, na histologia, demonstravam infiltrado granulomatoso. Cinco casos de intoxicações naturais por V. villosa foram diagnosticados no Setor de Patologia Veterinária da Universidade Federal do Rio Grande do Sul (SPV-UFRGS) no período de 2005 a 2010. As principais alterações macroscópicas observadas foram lesões alopécicas e crostosas de pele e múltiplos nódulos branco-acinzentados principalmente localizados nos linfonodos, rins e coração. Na histologia dos animais intoxicados visualizava-se macrófagos, linfócitos, células epitelioides e células gigantes multinucleadas, plasmócitos e eosinófilos. A intensidade do infiltrado granulomatoso variou entre os cinco casos analisados e entre os órgãos de cada animal. Os testes imuno-histoquímicos caracterizaram os infiltrados, que foram constituídos principalmente por linfócitos T e macrófagos. Os resultados dos testes de hipersensibilidade cutânea em bovinos com extratos protéicos da planta sugerem que os animais com a doença clínica apresentam uma resposta de hipersensibilidade tardia enquanto que os demais animais modulam a resposta imune diferentemente. / Vicia villosa was associated with poisoning in cattle, causing a systemic granulomatous disease. Hairy vetch poisoning is characterized by skin lesions and multiple whitish nodules in several organs. This work reports experimental poisoning by seeds and leaves of V. villosa in rabbits and cattle and the spontaneous poisoning by V. villosa in cattle is described. Rabbits received 5g/kg of seeds of hairy vetch and presented scaly, crusted lesions in ear and enlargement lymphoid tissue of intestine. Rabbits poisoned by hairy vetch leaves that were tested for cutaneous hypersensitivity showed enlargement of intestine lymphoid tissue. The histologic feature of this, lesion consisted of granulomatous inflammation. Cattle fed with seeds of hairy vetch (5g/kg) did not have clinical disease. Experimental poisoning by leaves of V. villosa in cattle did not present clinical signs; however, nodules in lymph nodes were observed. Histologically, infiltration of macrophages, lymphocytes and multinucleated giant cells were observed. Five cases of poisoning by V. villosa in cattle were diagnosed at Setor de Patologia Veterinária of Universidade Federal do Rio Grande do Sul (SPV-UFRGS) in the 2005 to 2010 period. Gross lesions were alopecia, skin crusts and multiple nodules mainly located in lymph nodes, kidneys and heart. Microscopically, infiltration of lymphocytes, macrophages, multinucleated giant cells, plasma cells and eosinophils were observed. Intensity of granulomatous infiltration varied among the five cattle and between analyzed organs. The inflammatory infiltration was characterized by immunohistochemistry. It was mainly composed of lymphocytes T and macrophages. Cutaneous hypersensitivity tests with hairy vetch proteins suggest that cattle with clinic disease have type-IV hypersensitivity reaction while others show different immune response.
4

Intoxicações experimentais e naturais por Vicia villosa em coelhos e bovinos.

Sonne, Luciana January 2010 (has links)
Vicia villosa foi relacionada a intoxicações em bovinos e causa uma doença granulomatosa sistêmica caracterizada por lesões de pele e múltiplos nódulos esbranquiçados em vários órgãos. Nesse trabalho realizou-se a intoxicação experimental por sementes e folhas de V. villosa em coelhos e bovinos. Os coelhos que receberam 5g/kg de sementes de ervilhaca apresentaram lesões descamativas e crostosas nas orelhas e evidenciação dos tecidos linfóides do intestino. Os coelhos intoxicados por folhas de ervilhaca e que receberam a aplicação para o teste de hipersensibilidade apresentaram evidenciação dos tecidos linfoides do intestino que corresponderam na histologia a infiltrado de histiócitos, linfócitos e células gigantes multinucleadas. O bovino alimentado com sementes de ervilhaca (5g/kg) não apresentou a doença clínica. Na intoxicação experimental por folhas de V. villosa, o bovino não apresentou sinais clínicos, porém houve aumento nodular dos linfonodos que, na histologia, demonstravam infiltrado granulomatoso. Cinco casos de intoxicações naturais por V. villosa foram diagnosticados no Setor de Patologia Veterinária da Universidade Federal do Rio Grande do Sul (SPV-UFRGS) no período de 2005 a 2010. As principais alterações macroscópicas observadas foram lesões alopécicas e crostosas de pele e múltiplos nódulos branco-acinzentados principalmente localizados nos linfonodos, rins e coração. Na histologia dos animais intoxicados visualizava-se macrófagos, linfócitos, células epitelioides e células gigantes multinucleadas, plasmócitos e eosinófilos. A intensidade do infiltrado granulomatoso variou entre os cinco casos analisados e entre os órgãos de cada animal. Os testes imuno-histoquímicos caracterizaram os infiltrados, que foram constituídos principalmente por linfócitos T e macrófagos. Os resultados dos testes de hipersensibilidade cutânea em bovinos com extratos protéicos da planta sugerem que os animais com a doença clínica apresentam uma resposta de hipersensibilidade tardia enquanto que os demais animais modulam a resposta imune diferentemente. / Vicia villosa was associated with poisoning in cattle, causing a systemic granulomatous disease. Hairy vetch poisoning is characterized by skin lesions and multiple whitish nodules in several organs. This work reports experimental poisoning by seeds and leaves of V. villosa in rabbits and cattle and the spontaneous poisoning by V. villosa in cattle is described. Rabbits received 5g/kg of seeds of hairy vetch and presented scaly, crusted lesions in ear and enlargement lymphoid tissue of intestine. Rabbits poisoned by hairy vetch leaves that were tested for cutaneous hypersensitivity showed enlargement of intestine lymphoid tissue. The histologic feature of this, lesion consisted of granulomatous inflammation. Cattle fed with seeds of hairy vetch (5g/kg) did not have clinical disease. Experimental poisoning by leaves of V. villosa in cattle did not present clinical signs; however, nodules in lymph nodes were observed. Histologically, infiltration of macrophages, lymphocytes and multinucleated giant cells were observed. Five cases of poisoning by V. villosa in cattle were diagnosed at Setor de Patologia Veterinária of Universidade Federal do Rio Grande do Sul (SPV-UFRGS) in the 2005 to 2010 period. Gross lesions were alopecia, skin crusts and multiple nodules mainly located in lymph nodes, kidneys and heart. Microscopically, infiltration of lymphocytes, macrophages, multinucleated giant cells, plasma cells and eosinophils were observed. Intensity of granulomatous infiltration varied among the five cattle and between analyzed organs. The inflammatory infiltration was characterized by immunohistochemistry. It was mainly composed of lymphocytes T and macrophages. Cutaneous hypersensitivity tests with hairy vetch proteins suggest that cattle with clinic disease have type-IV hypersensitivity reaction while others show different immune response.
5

Compara??o da toxicidade de Vicia villosa e Vicia sativa na alimenta??o de bovinos / Comparison of the toxicity of Vicia villosa and Vicia sativa in feed for cattle

VERONEZI, Luciane Orbem 27 July 2016 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2018-01-24T19:09:14Z No. of bitstreams: 1 2016 - Luciane Orbem Veronezi.pdf: 3213369 bytes, checksum: 660b54c56b80e667f1e30d110c395df3 (MD5) / Made available in DSpace on 2018-01-24T19:09:14Z (GMT). No. of bitstreams: 1 2016 - Luciane Orbem Veronezi.pdf: 3213369 bytes, checksum: 660b54c56b80e667f1e30d110c395df3 (MD5) Previous issue date: 2016-07-27 / CAPES / In this study the epidemiology, clinical signs, macroscopic and microscopic lesions related to spontaneous and experimental intoxication by Vicia villosa and the evaluation of the possible toxicity of Vicia villosa in cattle were characterized. The systematic granulomatous disease (SGD associated with vetch) was verified in 7 localities distributed in Paran?, Santa Catarina and Rio Grande do Sul States, with main feed that includes oats and/or ryegrass in association and V. villosa and/or ryegrass associated with Vicia sativa, and in lower quantity. All cattle that developed the disease were cows, lactating and Dutch. The SGD associated with vetch was reproduced in six lactating Dutch cows, by supplying green V. villosa in the trough and V. villosa and ryegrass pasture. In the other experimental groups (group 3, V. villosa / V. sativa/cows, grazing; group 4, V. sativa/cows, grazing; group 5, V. villosa/V. sativa/heifers and group 6, V. villosa/heifers, grazing) do not verified clinical and pathological alterations related to the SGD associated with vetch. Six cows developed the SGD, one cow presented a leigh clinical condition (group 2/cow 6/V. villosa, pasture), four cows developed a moderated clinical condition (group 1, cows 1 and 2/V. villosa/trough and group 2, cows 4 and 5/V. villosa, grazing), and just one cow presented a severe clinical condition (group 2, cow 3/V. villosa/pasture. V. villosa was toxic to cattle and produced a chronic granulomatous disease when ingested in amounts greater than 38.2 g/kg/day for 71 days, or in direct grazing for a period of more than 28 days The main clinical signs consisted of alopecia and cutaneous crusts, pruritus, fever, conjunctivitis, diarrhea, reduction of milk production and weight loss. Macroscopically, multiple white-grayish nodules were observed, specifically in the lymph nodes, kidneys and heart, and histology revealed a granulomatous infiltrate composed of macrophages, lymphocytes, giant cells, epithelioid cells, plasma cells and eosinophils. When ingested by young cattle, the V. villosa pasture, for a period of 68 days, do not produce clinical modifications. When ingested by cows with high milk yield, the V. sativa pasture, for a period of 78 days, does not produce chronic granulomatous disease. Ingestion of V. villosa for a long time led to low production rates, such as low milk production, low reproduction rates and predisposition to infection diseases. In the bromatological analysis, the presence of phytate, in low levels, in the samples of Vicia used in experimental works, in different phases of the culture was determined. The biochemical blood and feces results showing lower amounts of serum sinc and loss of Ca and Zn feces in animals poisoned by V. villosa, that developed granulomatous disease in severe and moderate conditions, possibly indicated the presence of a metabolic disorder in the pathogen of the disease. / No presente estudo caracterizou-se a epidemiologia, os sinais cl?nicos, as les?es macrosc?picas e microsc?picas da intoxica??o espont?nea e experimental por Vicia villosa, bem como a avalia??o da poss?vel toxicidade de Vicia sativa em bovinos. A doen?a granulomatosa sist?mica (DGS ervilhaca-associada) foi verificada em 7 propriedades distribu?das nos Estados de Santa Catarina, Paran? e Rio Grande do Sul, onde a alimenta??o principal era aveia e/ou azev?m consorciados com V. villosa e/ou de azev?m consorciado com V. villosa e em menor quantidade V. sativa. Todos os bovinos que desenvolveram a doen?a eram vacas, em lacta??o e da ra?a Holand?s. A DGS ervilhaca-associada foi reproduzida em seis vacas holandesas em lacta??o, atrav?s do fornecimento de V. villosa verde no cocho e em pastagens de V. villosa e azev?m. Nos demais grupos experimentais (grupo 3, V. villosa/V. sativa/vacas, pastejo; grupo 4, V. sativa/vacas, pastejo; grupo 5, V. villosa/V. sativa/novilhas e grupo 6, V. villosa/novilhas, pastejo) n?o verificou-se altera??es cl?nicas e patol?gicas relacionadas a DGS ervilhaca-associada. Das seis vacas que desenvolveram a doen?a granulomatosa sist?mica, uma vaca apresentou quadro cl?nico leve (grupo 2/vaca 6/V.villosa, pastejo), quatro vacas desenvolveram o quadro moderado da doen?a (grupo 1, vacas 1 e 2/V. villosa/cocho e grupo 2, vacas 4 e 5/V.villosa/pastejo) e apenas em uma vaca verificou-se o quadro grave da doen?a (grupo 2, vaca 3/V.villosa/pastejo). V. villosa foi t?xica para bovinos, produzindo doen?a granulomatosa cr?nica quando ingerida em quantidades superiores a 38,2g/kg/dia, por um per?odo de 71 ou, em pastoreio direto por um per?odo superior a 28 dias. As principais manifesta??es cl?nicas consistiam em ?reas de alopecia e crostas na pele, coceira, febre, conjuntivite, diarreia, queda na produ??o de leite e perda de peso. Macroscopicamente verificaram-se m?ltiplos n?dulos branco-acinzentados principalmente em linfonodos, rins e cora??o, e na histologia estes caracterizavam um infiltrado granulomatoso composto por macr?fagos, linf?citos, c?lulas gigantes, c?lulas epitelioides, plasm?citos e eosin?filos. As pastagens de V. villosa quando ingerida por bovinos jovens, por um per?odo 68 dias n?o produziu altera??es cl?nicas. As pastagens de V. sativa quando ingerida por vacas de alta produ??o leiteira por um per?odo de 76 dias n?o produziu doen?a granulomatosa cr?nica. A ingest?o de V. villosa por per?odos prolongados conduziu a baixos ?ndices produtivos como: baixa produ??o leiteira, baixos ?ndices reprodutivos e pode predispor o surgimento de doen?as infeciosas. Na an?lise bromatol?gica determinou-se a presen?a de fitato, em pequenas quantidades, nas amostras de Vicia utilizadas na experimenta??o, em diferentes fases do seu crescimento. Os resultados das an?lises bioqu?micas de amostras de sangue e fezes evidenciaram baixas quantidades s?ricas de zinco e excessivas perdas fecais de Ca e Zn nos animais intoxicados por V. villosa que desenvolveram a doen?a granulomatosa na forma moderada e grave, indicando um poss?vel envolvimento de dist?rbios de ordem metab?lica na patogenia da doen?a.
6

Intersiembra de leguminosa sobre Thinopyrum ponticum como mejoradora de la biomasa forrajera, valor nutricional y estado orgánico del suelo

Menghini, Mariano 17 April 2018 (has links)
La incorporación de leguminosas en los agroecosistemas ganaderos, presenta una serie de ventajas productivas y ambientales, respecto a los sistemas basados únicamente en gramíneas. El objetivo del trabajo fue analizar el efecto de la incorporación de leguminosas en pasturas puras de agropiro alargado (Thinopyrum ponticum) en la región semiárida. Para ello, se condujeron una serie de experimentos con el objetivo de evaluar específicamente (1) el efecto de la intersiembra con vicia (Vicia villosa) sobre la biomasa forrajera, valor nutricional de la pastura y dinámica de las fracciones orgánicas del suelo en tres ambientes del sudoeste bonaerense (Bahía Blanca, Tornquist y Cabildo), (2) el efecto de la densidad de intersiembra con vicia o trébol de olor blanco (Melilotus albus), sobre los cambios de valor nutricional en función de la composición botánica, y por último, (3) determinar el momento de corte óptimo para la confección de reservas (heno o ensilaje) y estudiar el efecto de la incorporación de grano de cereal en ensilaje de pasturas consociadas. Las mezclas forrajeras se realizaron intersembrando vicia o trébol en otoño de cada año, sobre agropiro implantado. El forraje se cortó manualmente, sobre una superficie de 0,4 m2 y la frecuencia de defoliación estuvo basada en el crecimiento de agropiro. Durante un período de dos años sobre una pastura monofítica de agropiro y una consociación con vicia (20 kg ha-1), se evaluó la biomasa forrajera y su valor nutricional (FDN, FDA, LDA, DIVMS y PB). Durante este ensayo se realizó un fraccionamiento físico del suelo, para separar las diferentes fracciones que componen la materia orgánica hasta la profundidad de 0-20 cm. En otro ensayo, se decidió estudiar el efecto de las densidades de intersiembra, se incluyeron en este caso dos especies de leguminosas (vicia o trébol). Ambas, se intersembraron separadamente a tres densidades diferentes, en función de plantas agropiro:leguminosa (80:20, 70:30 y 60:40). Por su parte, para el estudio de reservas forrajeras, en otro ensayo, se cortó una pastura pura de agropiro en cinco estados fenológicos, desde vegetativo (7/11/2012) hasta grano pastoso (14/02/2013) para la elaboración de heno y ensilaje en cada fecha. Con esta información, en un último ensayo se estudió el efecto de la inclusión de una leguminosa (trébol) y grano de avena en ensilajes de agropiro. Las mezclas de forraje y grano se realizaron en laboratorio combinando tres proporciones de trébol (T0: sin trébol, agropiro puro; T20: 20% trébol y T40: 40% trébol) y dos niveles de grano (G0: sin grano y G1: 30% de grano) en base a la MS. Cuando se intersiembra vicia o trébol sobre agropiro, se registró en todos los sitios un aumento en la producción forrajera anual que fue del 28 a 190%, salvo para la localidad de Cabildo que la producción no cambió (p=0,08). Analizando la producción de agropiro separadamente no se observa una disminución con la inclusión de vicia. Por lo tanto, se entiende que la leguminosa acompañante, explora recursos que el agropiro no hace. En cambio, se encontró que trébol ejerció una competencia con agropiro avanzada la primavera, porque a medida que aumentó la biomasa de trébol disminuyó linealmente la biomasa de agropiro. Comparando la producción forrajera de vicia y trébol, ambas especies mostraron una buena capacidad de compensación en el crecimiento, ya que no mostraron diferencias en el rendimiento a diferentes densidades. En general, la intersiembra con leguminosas aumenta el contenido de PB (entre 1,0 y 1,4% cada 10% de leguminosa en la composición), DIVMS y LDA de la pastura, mientras que disminuyó los contenidos de FDN (1,5% cada 10% de leguminosa) y FDA. Además, se identificó trasferencia de nitrógeno de vicia y trébol hacia agropiro por mayor contenido de PB del agropiro consociado, tanto en primavera como en otoño. La inclusión de vicia incrementó el contenido de Carbono orgánico particulado (COP) grueso (hasta 42%) y fino (hasta 13%) del suelo, sin modificar el contenido de carbono orgánico total. Para Cabildo y Bahía Blanca la inclusión de vicia también generó un aumento (12%) del nitrógeno de la materia orgánica particulada. Respecto a la elaboración de reservas de agropiro, se encontró que el heno mantuvo mejor el valor nutricional que el ensilaje. Aunque, la mayor fuente de variación se relacionó al estado fenológico de la pastura en el momento de corte y no al tipo de reserva elaborada. Para la elaboración de un adecuado ensilaje de agropiro, el período óptimo de corte va desde espiga embuchada a antesis, mientras que para henificación el período óptimo es mayor, desde estado vegetativo hasta antesis. La incorporación de una leguminosa como el trébol y el grano de avena al ensilaje de agropiro generó aumentos en el contenido de PB y disminuciones en FDN, FDA. La adición de grano, mejora la DIVMS en los tratamientos con menor cantidad de trébol (T0 y T20). A medida que aumentó la participación de trébol, los valores de pH se incrementaron progresivamente de 3,78 (T0) a 4 (T40). Sin embargo, la adición de grano generó una disminución de pH. El ensilaje con trébol de olor blanco hasta el 40%, no presentó un problema para la realización de un adecuado ensilaje, resultando la mejor alternativa junto con la incorporación de grano. / The inclusion of legumes in livestock agroecosystems have production and environmental advantages, compared to systems based only on grasses. The objective of this work was to analyze the effect of the inclusion of legumes in pure pastures of tall wheatgrass (Thinopyrum ponticum). A series of experiments were conducted with the objective of evaluating, (1) the effect of interseeding hairy vetch (Vicia villosa) over the forage biomass, nutritional value of pasture and dynamics of soil organic matter fractions in three representative semiarid environments of the Buenos Aires province, Argentina (Bahía Blanca, Tornquist and Cabildo), (2) the effect of the density of interseeding with hairy vetch or white sweetclover (Melilotus albus) over nutritional value depending on the botanical composition, and finally, (3) determining the optimal cutting moment for the preparation of reserves and study the effect of the incorporation of grain in silage of mixture pastures. The forage mixtures were made by interseeding hairy vetch or clover in the autumn of each year, on implanted tall wheatgrass. The forage was cut manually, on a surface of 0,4 m2 and the frequency of defoliation was based on the growth of tall wheatgrass. During a two-year period, on tall wheatgrass monoculture and mixture with hairy vetch (20 kg ha-1), biomass yield and its nutritional value (NDF, ADF, ADL, IVDMD and CP) were evaluated. During this period, soil organic matter fractions were separated by size using a wet-sieving method up to the depth of 0-20 cm. Besides, to study the effect of interseeded densities, another test was realized that included two species of legumes (hairy vetch or white sweetclover). Separately, both legumes were interseeded at three different densities based on the tall wheatgrass:legume plant relationships of 80:20, 70:30 and 60:40. Finally, for the study of reserves, a pure pasture of tall wheatgrass was cut in five phenological stages from vegetative (11/7/2012) to dough-grain (2/14/2013) for the preparation of hay and silage on each date. With this information, in another trial the effect of the inclusion of a legume (clover) and grain of oats in silages of tall wheatgrass was studied. The mixtures of forage and grain were made in the laboratory combining three proportions of clover (T0: without clover, pure tall wheatgrass, T20: 20% clover and T40: 40% clover) and two grain levels (G0: no grain and G1: 30 % grain) based on the MS. When hairy vetch or clover was interseeded over tall wheatgrass, an increase in annual yield biomass was recorded from 28 to 190%, except in Cabildo, where production did not change. Analyzing tall wheatgrass biomass separately, there is no decrease in production with hairy vetch inclusion. Therefore, the accompanying legume, seems to use the resources that tall wheatgrass leaves available. Instead, the clover competed with tall wheatgrass in late spring, thus, as the biomass of clover increased, the biomass of tall wheatgrass decreased linearly. Hairy vetch and clover plants showed growth compensation because there was no difference in forage yield at different density. In general, the hairy vetch or clover interseeding increased total CP (between 1,0 - 1,4% every 10% of legume in the composition), IVDMD and ADL, while the NDF (1,5 % every 10% of legume in the composition) and ADF decreased. In addition, the nitrogen transfer from the legume appear to be responsible for the increase in the CP content of tall wheatgrass when growing together. This was evident in both seasons spring and fall. Hairy vetch increased the content of particulate organic carbon (POC) in fraction >105μm (up to 42%) and fraction between 53 and 105 μm (up to 13%) of the soil. The total organic carbon in soil (SOC) content did not change, therefore the relationship (POC/SOC) was increased. For Cabildo and Bahía Blanca hairy vetch inclusion enhanced the N content (12%) of the particulate organic matter. Regarding the preparation of wheatgrass reserves, it was found that hay maintained its nutritional value better than silage. Although, the greatest source of variation can be attributed to the phenological stage of the pasture and to a lesser extent to the type of reserve. For the best silage of tall wheatgrass, the optimal cutting period was from booting to anthesis, whereas, for haymaking the optimal period extends from vegetative to anthesis. Inclusion of clover and grain increased silage CP content and decreased NDF and ADF. In addition, grain incorporation improved IVDMD in treatments with less clover (T0 and T20). The highest proportion of clover in the mixture reduced FDN and FDA. As clover participation was greater, the silage pH values increased progressively from 3.78 (T0) to 4 (T40). However, the addition of grain decreased pH. According to these results, a silage including white sweetclover up to 40%, was not a restriction to obtain a fairly good quality silage, being the best alternative when also combined with grain.

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