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Effects of sowing and fertilisation in the establishment of annual legume rich permanent pastures

Aguiar, Carlos; Pires, Jaime; Rodrigues, M.A.; Fernández-Núñez, E.
Fonte: European Grassland Federation (EGF) Publicador: European Grassland Federation (EGF)
Tipo: Artigo de Revista Científica
ENG
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35.92%
A field experiment tested the effect of three fertilisation strategies (nil, mineral and organic fertilisation) on pasture establishment, measured by plant species composition in spring sward in the two first years after sowing two pasture types (simple annual, legume-rich mixture and complex annual legume-rich mixture) compared with unsown pastures. There was a positive effect of organic fertilisation on the spring floristic composition through the increase of sown annual legumes, without an increase of ruderal species. Farmyard manure substituted, with advantages, conventional sowing mineral fertilization in these conditions.

Avaliação de pastagem de Capim-Braquiária em degradação e sua recuperação com suprimento de nitrogênio e enxofre.; Evaluation of signal grass pastures under degradation and its recovery through the supply of nitrogen and sulfur.

Mattos, Waldssimiler Teixeira de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 28/06/2001 PT
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O presente trabalho foi desenvolvido com o objetivo de avaliar as condições de pastagens em degradação e a influência do nitrogênio e do enxofre na recuperação de Brachiaria decumbens Stapf. em estado de degradação. O estudo foi realizado em duas etapas. A primeira consistiu no levantamento das condições nutricionais da forrageira em duas áreas contíguas, sendo uma não recentemente adubada e outra recentemente adubada. Foram coletadas folhas diagnósticas e raízes, bem como foram realizadas avaliações do teor de clorofila. Amostras de solo nas camadas de 0 a 10 cm e 10 a 20 cm também foram coletadas para a avaliação de fertilidade do solo. O solo amostrado na área recentemente adubada apresentou teores mais elevados de matéria orgânica, B, Cu, Fe e Zn em ambas camadas, que aquele da área não recentemente adubada. O capim na pastagem da área recentemente adubada apresentou concentrações mais elevadas de N, Cu, Fe e Zn que o capim da área não recentemente adubada. A segunda etapa, constituída de dois experimentos, foi conduzida em casa-de-vegetação com a utilização de 96 cilindros de solo contendo capim-braquiária, coletados nas áreas em estudo e colocados em vasos plásticos. Empregou-se um esquema fatorial 4 x 3 (doses de nitrogênio e de enxofre) perfazendo 12 combinações...

"Respiração do solo sob florestas e pastagens na Amazônia Sul-Ocidental, Acre"; soil respiration under forests and pastures in Southwestern Amazonia, Acre

Salimon, Cleber Ibraim
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 14/05/2003 PT
Relevância na Pesquisa
26.1%
A conversão de florestas em pastagens e seu subseqüente abandono tem ocorrido por toda Amazônia, e embora exista muita pesquisa sobre as conseqüências desta mudança de cobertura do solo, ainda existem muitas perguntas sobre os processos biogeoquímicos associados a estas mudanças. Neste estudo, nós avaliamos os efeitos da mudança de cobertura sobre a respiração do solo em pastagens e florestas secundárias e intactas próximo de Rio Branco, Acre. Utilizou-se o método de câmaras dinâmicas associadas com analisador de gás por infravermelho. As folhas de gramíneas dentro dos anéis de medida nas pastagens foram responsáveis por cerca de 50% do fluxo durante a estação chuvosa, mas na estação seca, sua influência pode ser confundida com a variabilidade entre os anéis de medida. Os maiores fluxos de CO2 são observados em pastagens e não em florestas, mesmo se descontado o efeito das folhas em pastagens. As maiores amplitudes de variação sazonal também foi observada em pastagens. Devido aos maiores fluxos em pastagens, o fluxo anual de CO2 do solo para atmosfera foi 20% maior em pastagens em comparação com as florestas. A respiração heterotrófica é similar em pastagens e florestas secundárias e intactas...

Avaliação de co-produtos na alimentação de vacas leiteiras mantidas em pastagens tropicais durante a estação chuvosa e alimentadas no cocho durante a estação seca do ano; Evaluation of byproducts inclusion on concentrate supplements for dairy cows grazing tropical pastures during rainy season and confined during dry season

Martinez, Junio Cesar
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 05/08/2008 PT
Relevância na Pesquisa
36.1%
O presente estudo teve por objetivo avaliar o uso de co-produtos na composição de concentrados fornecidos para vacas em lactação em pastagens de capim elefantes durante a estação chuvosa e alimentadas no cocho com cana-de-açúcar durante a estação seca. Todos os trabalhos foram conduzidos no Departamento de Zootecnia da ESALQ/USP, Piracicaba - SP. O primeiro experimento estudou a inclusão de 0, 14 e 34% de caroço de algodão na dieta de 16 vacas Holandesas alimentadas no cocho durante a estação seca e tendo cana-de-açúcar como base (62,7% da MS), em delineamento de QL 4x4 com quatro repetições. As análises estatísticas foram realizadas utilizando-se o procedimento GLM do SAS. Os tratamentos afetaram a produção e composição do leite, consumo de matéria seca e consumo de lipídios, mas não afetaram o peso vivo, condição corporal e parâmetros sanguíneos. Portanto, o caroço de algodão pode ser utilizado em dietas com cana-de-açúcar quando incluído em até 17% da MS total. O segundo experimento substituiu o milho moído fino em até 75% por farelo de glúten de milho no concentrado oferecido para vacas mantidas em pastagens tropicais durante a estação chuvosa. A pastagem foi adubada com 80 kg de N/ha para cada ciclo de pastejo que teve intervalo de desfolha de 23 dias. O delineamento estatístico adotado foi em Quadrado Latino 4 x 4 com quatro repetições das os dados de desempenho e comportamento ingestivo. O estudo avaliando metabolismo ruminal foi realizado com somente um Quadrado Latino. As análises estatísticas foram realizadas através dos procedimentos GLM e MANOVA do SAS (2002). Utilizou-se 16 animais da raça Holandesa com 485 kg de PV e 141 dias de lactação. Os tratamentos não afetaram a produção e a composição do leite...

Pre- and post-calving forage systems and reproductive performance of primiparous cows

Lobato, Jose Fernando Piva; Menegaz, André Luís; Pereira, Antônio Carlos Gonçalves
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
ENG
Relevância na Pesquisa
26.15%
Durante os períodos pré e pós-parto, foi avaliada a influência de sistemas forrageiros no desempenho reprodutivo de vacas primíparas: pastagem natural nos períodos pré e pós-parto; pastagem natural no pré-parto e pastagem melhorada no pós-parto; pastagem melhorada no pré-parto e pastagem natural no pós-parto; pastagem melhorada nos períodos pré e pós-parto. Os menores pesos e condições corporais foram observados nas vacas mantidas em pastagem natural no pré-parto, (384,3 kg e 3,31; 391,4 kg e 3,60), seguidas daquelas em pastagem melhorada no pré-parto e natural no pósparto (424,4 kg e 3,60); e, por ultimo, das vacas em pastagem melhorada no pré e pós- parto (421,2 kg e 3,59). As vacas em pastagem melhorada no pré e pós-parto tiveram maior peso e condição corporal ao início do acasalamento (442,1 kg e 3,76), maior taxa de prenhez (82,3%) e emprenharam mais cedo. Os sistemas com pastagem natural no pré-parto e melhorada no pós-parto e aquele com pastagem melhorada no pré-parto e natural no pós-parto não diferiram quanto a peso ao início do acasalamento (417,2 e 409,8 kg) e taxa de prenhez (65,8 e 62,8%), respectivamente. Entretanto, as vacas em pastagem natural no pré-parto e melhorada no pós-parto emprenharam mais cedo. As vacas mantidas em pastagem natural tiveram o menor peso ao início do acasalamento (391...

Evaluation of long-term use of precision agriculture techniques in permanent pastures in Alentejo

Serrano, João M.; Peça, José M.; Shahidian, Shakib; Marques da Silva, José
Fonte: CIGR-AgEng Publicador: CIGR-AgEng
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
35.99%
This work evaluates the results of implementing precision agriculture technologies in dry land permanent pastures in the southern region of Portugal over a six year period. A project provided the means for the acquisition of precision farming technologies and demonstration of their potential and limitations in experiments carried out on a 6 ha field with a biodiverse pasture. The technologies sought, on the one hand, to simplify the time-consuming and expensive process of evaluating the soil characteristics and productivity of the pasture and on the other, to optimize the application of fertilizers, the main practice used by farmers to improve pastures. The use of a "DUALEM 1S" electromagnetic induction sensor in association with a GPS receiver allowed the identification of areas in the plot with different potentials and production capacities. The use of a "GRASSMASTER II" probe associated with a GPS receiver, after calibration, proved to be a very interesting tool in non-destructive and rapid assessment of pasture productivity. Through the combination of "FIELDSTAR" and "FERTICONTROL" systems it was possible to control a "VICON RS-EDW" centrifugal fertilizer distributor equipped with variable rate technology (VRT). Closing the cycle in precision agriculture with differentiated application of phosphate fertilizers is an important step in rationalizing the use of economic resources and environmental protection.

Organic C distribution and N mineralization in soil of oak woodlands with improved pastures

Gómez-Rey, Maria Xesús; Garcês, Ana; Madeira, Manuel
Fonte: SCAP Publicador: SCAP
Tipo: Artigo de Revista Científica
Publicado em //2011 ENG
Relevância na Pesquisa
26.07%
Cork oak woodlands in Portugal are a multipurpose agroforestry system occurring in areas mostly degraded by former cereal crops and overgrazing. The objective of this study was to evaluate the effect of scattered cork oak trees (Quercus suber L.) on soil quality, considering two land use systems: unmanaged pastures and improved pastures. Soil samples were collected in a square grid around scattered cork oak trees to evaluate the spatial variability of soil bulk density and chemical properties. In soil samples taken beneath tree canopy and in the open, net N mineralization was evaluated by aerobic incubations. Also, laboratory incubations were carried out to evaluate the effect of roots (tree or/and herbaceous) and water solutions (bulk precipitation, throughfall or stemflow) on net N mineralization. Contents of organic C, total N and extractable P were increased beneath the tree canopy, and gradually decreased with the increase of distance to the tree trunk. Improved pastures established 26 years ago increased organic C (0.76 kg m-2), total N (0.06 kg m-2) and extractable P (2.70 g m-2) amounts in the 0-10 cm soil layer beneath the tree canopy relatively to those of unmanaged pastures. Net N mineralization was significantly greater (about 2 times) in soils beneath the tree canopy than in those of open areas. N mineralization was unaffected by addition of throughfall or stemflow...

Phenology, fruit set and dispersal of Cordia multispicata Cham., an important weed shrub of abandoned pastures in eastern Amazonia

Vieira,Ima Célia Guimarães; Silva,José Maria Cardoso da
Fonte: Sociedade Botânica de São Paulo Publicador: Sociedade Botânica de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/1997 EN
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ABSTRACT - (Phenology, fruit set and dispersal of Cordia multispicata Cham., an important weed shrub of abandoned pastures in eastern Amazonia). The reproductive ecology of the distylous tropical shrub Cordia multispicata was studied in an abandoned pasture in Paragominas County , Pará state, Brazil. It is a common species in the Amazon basin where it occurs as a weed in open and disturbed habitats. C. multispicata has many flowers per inflorescence (85 ± 12) but 84% abort before fertilization. Flowering occurs throughout the year. Fruits are small, with a red fleshy pericarp (skin-pulp) attractive to birds. Fruit set is lower during the dry season (less than 30%) and higher during the rainy season when there are many visits of insects to the flowers. Fruiting has a peak between the end of the dry season and the middle of the rainy season. Nineteen bird species were observed foraging for the fruits of C. multispicata, and 79% of those species can be considered as potential dispersal agents. The efficient seed dispersal and aggregated spatial distribution associated with some characteristics of the dispersors greatly contributed to the success of this species in abandoned pastures of eastern Amazonia.

Sward structure and livestock performance in guinea grass cv: Tanzania pastures managed by rotational stocking strategies

Euclides,Valéria Pacheco Batista; Montagner,Denise Bataglin; Difante,Gelson dos Santos; Barbosa,Rodrigo Amorim; Fernandes,Wellington Souza
Fonte: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz" Publicador: São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2014 EN
Relevância na Pesquisa
26.07%
Grazing strategy is a key element in the determination of sward structure, herbage nutritive value and animal performance. We aimed to compare the herbage characteristics and performance of livestock in pastures of Panicum maximum cv. Tanzania managed, using two rotational stocking strategies, which provided either a fixed-length rest period (FRP) of 35 days in the spring and fall and 30 days in the summer, or a variable-length rest period (VRP), determined by the time required for the canopy to achieve 70 cm in height. The pastures were evaluated in the pregrazing condition for forage mass (FM); leaf (LP), stem (SP) and dead matter (DP) percentages; and nutritive value (NV). The animals were weighed every 28 days. Pastures managed with the FRPs exhibited greater FMs, SPs and DPs and lower LPs and NVs than those managed with the VRPs. The average daily livestock weight gain was greater during the spring and summer for the VRP than for the FRP pastures, resulting in an average animal weight gain per area of 990 and 860 kg ha−¹ wet period−¹ for the pastures managed with the VRPs and FRPs, respectively. Thus, pasture rest periods that were maintained after the sward reached 70 cm in height reduced the animal performance on Tanzania guinea grass.

Pre- and post-calving forage systems and reproductive performance of primiparous cows

Lobato,José Fernando Piva; Menegaz,André Luís; Pereira,Antonio Carlos Gonçalves
Fonte: Sociedade Brasileira de Zootecnia Publicador: Sociedade Brasileira de Zootecnia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2010 EN
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26.15%
During pre and post calving periods, it was evaluated the influence of the following forage systems on reproductive performance of primiparous cows: natural pasture during pre and post-calving periods; natural pastures during pre-calving period and improved pastures during post-calving period; improved pastures during pre-calving and natural pasture during post-calving; improved pasture during pre- and post-calving periods. The lowest body weights and body condition scores were observed on cows kept on natural pastures pre-calving (384.3 kg and 3.31; 391.4 kg and 3.60), followed by those on improved pastures during pre-calving and on natural pasture during post-calving period (424.4 kg and 3.60), finally, cows on improved pasture during pre- and post-calving period (421.2 kg and 3.59). Cows on improved pastures pre and post-calving showed higher body weight and body condition score in the beginning of the breeding season (442.1 kg and 3.76), higher pregnancy rate (82.3%) and they conceived earlier. Natural system during pre-calving and improved on post-calving and that with improved pasture in pre-calving and natural in post-calving did not differ on weight at the beginning of breeding season (417.2 and 409.8 kg) and on pregnancy rate (65.8 and 62.8%)...

Natural and improved natural pastures on the reproductive performance of first-calf beef cows

Tanure,Soraya; Pötter,Bernardo Augusto Albornoz; Lobato,José Fernando Piva
Fonte: Sociedade Brasileira de Zootecnia Publicador: Sociedade Brasileira de Zootecnia
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2011 EN
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This work evaluated the reproductive performance of first-calf cows at three years of age, submitted or not to protein supplementation at yearling on natural pastures. After calving, cows were managed on natural or improved pastures. The feeding managements were the following: on natural pastures as yearlings and during pregnancy, post-calving period and breeding season; on natural pastures with protein supplement as yearlings and only natural pasture during pregnancy, post-calving and breeding season; on natural pastures as yearlings and during pregnancy and on improved natural pastures (Lolium multiflorum L., Trifolium repens cv. Yi and Lotus corniculatus cv. São Gabriel) during the post-calving period and breeding season; on natural pastures with protein supplement at yearling, on natural pastures during pregnancy, and on improved natural pasture during post-calving period and breeding season. Cows did not differ on body weight, but from calving to the beginning of breeding season, cows on improved natural pastures presented higher weight gain than those on natural pastures (0.203 vs. 0.109 kg/day). Cows in post-calving on natural pastures lost 1.0 point of body condition score during mating, determinant of the lowest pregnancy rate and later conception in relation to cows on improved natural pasture. Pregnant cows presented higher body weight (440 vs. 413 kg) and body condition score (4.14 vs. 3.66 points) than open cows at the end of the breeding season.

Performance of dairy heifers grazing on Urochloa decumbens pastures deferred for two periods

Teixeira,Fábio Andrade; Silva,Fabiano Ferreira da; Bonomo,Paulo; Pires,Aureliano José Vieira; Nascimento,Paulo Valter Nunes; Gonçalves Neto,João
Fonte: Editora da Universidade Estadual de Maringá - EDUEM Publicador: Editora da Universidade Estadual de Maringá - EDUEM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2014 EN
Relevância na Pesquisa
36.04%
Voluntary intake and performance of dairy heifers grazing on Urochloa decumbens pastures with two deferral periods are evaluated. The totally randomized experimental design consisted of two treatments and seven replications, with two deferral periods: T1 = 95 and T2 = 140 days. Fourteen Holstein-Zebu heifers, average body weight (BW) 300 kg, were used. Intake of forage dry matter was 2.5% and 1.2 BW respectively for treatments 95 and 140 days. In treatment T2 the animals had an intake of only 139.5 g of CP, due to low nutrient content, or rather, 3.4% of CP in the forage available. There was an intake of NDF of 1.7% and 1.0 of BW for T1 and T2, respectively. The average daily weight gain was 785.8 g day-1 for T1 and average weight loss of -31.1 g day-1 for T2. Deferral of pastures Urochloa decumbens for 95 days to allow a 1.5 lodging index provides greater consumption and performance of dairy heifers. Deferral of Urochloa decumbens pastures to allow a 1.5 lodging index provides greater intake and performance of dairy heifers.

Cool-season annual pastures with clovers to supplement wintering beef cows nursing calves

Gunter, Stacey A; Whitworth, Whitney A; Montgomery, T Gregory; Beck, Paul A
Fonte: BioMed Central Publicador: BioMed Central
Tipo: Artigo de Revista Científica
Publicado em 24/07/2012 EN
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26.1%
In December of 3 years, 87 beef cows with nursing calves (594 ± 9.8 kg; calving season, September to November) at side were stratified by body condition score, body weight, cow age, and calf gender and divided randomly into 6 groups assigned to 1 of 6 cool-season annual pastures (0.45 ha/cow) that had been interseeded into a dormant common bermudagrass (Cynodon dactylon [L.] Pers.)/bahiagrass (Paspalum notatum Flugge) sod. Pastures contained 1 of the following 3 seeding mixtures (2 pastures/mixture): 1) wheat (Triticum aestivum L.) and ryegrass (Lolium multiflorum Lam., WRG), 2) wheat and ryegrass plus red clover (Trifolium pretense L., WRR), or 3) wheat and ryegrass plus white (Trifolium repens L.) and crimson clovers (Trifolium incarnatum L., WRW). All groups had ad libitum access to grass hay (12% crude protein; 58% total digestible nutrients). The second week in December, cow estrous cycles were synchronized and artificially inseminated. In late December, a bull was placed with each group for 60-d. Data were analyzed with an analysis of variance using a mixed model containing treatment as the fixed effect and year as the random effect. Body weight and condition scores did not differ (P ≥ 0.27) among cows between February and June. Calf birth weights or average daily gain did not differ (P ≥ 0.17) among treatments; however...

Monitoramento das pastagens cultivadas no cerrado goiano a partir de imagens MODIS índices de vegetação (MOD13Q1); Monitoring cultivated pastures in the Cerrado Goiano Image from MODIS vegetation index (MOD13Q1)

GARCIA, Fanuel Nogueira
Fonte: Universidade Federal de Goiás; BR; UFG; Mestrado em Geografia; Ciências Humanas Publicador: Universidade Federal de Goiás; BR; UFG; Mestrado em Geografia; Ciências Humanas
Tipo: Dissertação Formato: application/pdf
POR
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Cattle ranching is extremely important for the economy of Brazil. This activity is characterized by the intensive explotation of pastures, which occupy a vast area of the Brazilian territory, i.e. approximately 150 million hectares. Currently, Brazil is the largest meat exporter in the world. Concerning its biomes, this occupation occurs mainly in the Cerrado, where the 546.251 km² of area under utilization correspond to about 37% of the total pasture area in the country. Among the states encompassed within the Cerrado limits, Goiás has the largest pasture occupation, over 38.7% of its area. In addition, it has one of the largest livestock, with about 21.3 millions of heads, producing, on average, 600.000 tons of meat a year. Within this context, arises the concern with the quality of the Goias state pastures, since several studies show that a large portion of these pastures are already degraded (i.e. low capacity), with low cattle occupation. This study, based on remote sensing data, as well as on spatial and census data, aimed at evaluating the quality of the pastures in Goias through the estimation of the net primary productivity (NPP). The distribution of pastures in relation to soil types, cattle occupation at the municipality level...

Relaciones entre el índice espectral de vegetación NDVI y la cobertura vegetal en pastos de puerto del Pirineo Occidental; Relationship between Normalized Difference Vegetation Index (NDVI) and total plant cover in Pyrenean summer pastures

Campo, Arancha; García-González, Ricardo; Marinas, A.; Gartzia, Maite
Fonte: Asturias (Comunidad Autónoma). Consejo de Gobierno Publicador: Asturias (Comunidad Autónoma). Consejo de Gobierno
Tipo: Comunicación de congreso Formato: 131215 bytes; application/pdf
SPA
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7 págs.-- Comunicación presentada a la XLV Reunión Científica de la Sociedad Española para el Estudio de los Pastos: "Producciones agroganaderas: gestión eficiente y conservación del medio natural" (Gijón, 28 de mayo al 3 de junio de 2005).; [ES] En los pastos de puerto de alta montaña la cobertura total de la vegetación condiciona fuertemente la capacidad de carga. En grandes superficies a menudo es difícil evaluar esta variable con precisión. Las técnicas de teledetección vía satélite que incorporan sensores espectrales para establecer índices de vegetación, se han demostrado muy útiles para paliar este problema. En este trabajo se calcularon índices de vegetación de diferencia normalizada (NDVI) a partir de tres escenas espectrales de un puerto del Pirineo occidental y se relacionaron con la cobertura vegetal establecida a partir de un mapa de vegetación escala 1:5000. Se pretende encontrar un modelo de predicción generalizable que permita la clasificación por clases de cobertura vegetal de los pastos de puerto pirenaicos a partir de imágenes de satélite. De las tres escenas satelitales (junio'93, agosto'91 y octubre'99), la que mejor discriminó los intervalos de cobertura fue la de agosto'91. Se tomaron tres métodos de clasificación de los NDVI y se analizó su correspondencia con la clasificación de coberturas establecida en el mapa 1:5000. Ninguno de ellos proporcionó una clasificación satisfactoria. Se concluye que son necesarios nuevos ensayos de clasificación reduciendo los intervalos de cobertura...

Evaluation of sheep grazing as a tool to restore mountain pastures invaded by Euphorbia polygalifolia; Evaluation d'ovins au pâturage comme instrument pour restaurer les pâtures de montagne infestées par Euphorbia polygalifolia

Mora Martínez, Manuel José; Busqué, Juan; Hervás, Gonzalo; Mantecón, Ángel R.; Fernández, Begoña; Frutos, Pilar
Fonte: Centre international de hautes études agronomiques méditerranéennes; Food and Agriculture Organisation of the United Nations Publicador: Centre international de hautes études agronomiques méditerranéennes; Food and Agriculture Organisation of the United Nations
Tipo: Comunicación de congreso Formato: 4657211 bytes; application/pdf
ENG
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26.1%
6 pages, 1 table, 2 figures.-- Contributed to: 11th Seminar of the FAO-CIHEAM Sub-Network on Sheep and Goat Nutrition (Catania, Italy, Sep 8-10, 2005); [EN]Two experiments were conducted to (i) study whether sheep grazing pastures infested by a spurge (Euphorbia polygalifolia) consume this invasive weed and its consequences on animal performance, and (ii) detect differences betwen sheep and cattle in ruminal degradation of infested pastures. In the first trial, sheep grazed fenced paddocks highly invaded by spurge at instantaneous stocking rates of 120 ewes/ha/week Spurge offtake, sward height and ewes body weight were measured weekly from mid-June to September. An average of 63% of the initial spurge growing points was defoliated per week. Sward height showed a negative curvilinear relationship with the proportion of spurge defoliated, with high spurge defoliation occurring when sward height was lower than 4 cm. Variation in body weight was mainly related to sward height (r = 0.86; P<0'10) and apparent signs of intoxication were never observed. In the second experiment, 6 cows and 8 ewes were distributed according to a factorial design: 2 species (cattle vs sheep) x 2 grazing areas (infested vs non-infested pastures). After seventeen days...

The soil seed bank in abandoned tropical pastures: source of regeneration or invasion?

López-Toledo,Leonel; Martínez-Ramos,Miguel
Fonte: Instituto de Biología Publicador: Instituto de Biología
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2011 EN
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26.1%
We assessed the availability of both pioneer and non-native species in the soil seed bank of old-growth forest and recently abandoned pasture, to evaluate whether the soil seed bank in these pastures represents a source of regeneration of species from adjacent old-growth forest or of invasion by non-native species. Our study was conducted at Selva Lacandona, Chiapas, Mexico. Soil samples were randomly collected from 6 sites in old-growth forest, and 6 sites in abandoned pastures. Seedlings from soil samples were identified and classified into pioneer, non-native (weeds/graminoids), and other forest species. Pioneer species seeds were virtually absent in pastures, but represented ~30% of seeds in the forest. Non-native species comprised ~99% of the soil seed bank in pastures. In the forest, soil seed bank density of weeds and graminoids decreased with increasing distance (up to 4 km) from agricultural fields, and comprised up to 25% (Mean ± 1SE= 16 ± 7) of the seed bank. Our results show a near total elimination of pioneer species from the soil seed bank in pastures, and considerable invasion of the borders of the Montes Azules reserve by seeds of non-native species. Thus, in the region studied, the soil seed bank in abandoned pastures represents a source of invasion by non-native species into old-growth forest rather than a potential source of forest regeneration.

The economic viability of finishing Nguni weaners on natural veld and permanent pastures

Nowers,C.B.; Welgemoed,J.
Fonte: South African Journal of Animal Science Publicador: South African Journal of Animal Science
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2010 EN
Relevância na Pesquisa
36.07%
The objective of this study was to investigate the economic viability of finishing Nguni weaners on natural veld and permanent pastures under dry land conditions. A group of 30 Nguni calves (7-9 months age) were randomly divided into two treatment groups: a group on Eastern Province Thornveld (Veld group) and a group managed on Panicum maximum pastures. The average daily gain (ADG) of the weaners in the Pasture group (0.606 kg/day) during this period was significantly higher than weaners on natural veld (0.434 kg/day). The profit per weaner (margin above direct allocated costs) in the Veld group was R246.56 higher than that of calves in the Pasture group but the highest return per ha was obtained from weaners raised on permanent pastures. These findings suggest that it was still more economic viable to finish Nguni weaners on the more costly Panicum pastures than on natural Eastern Province Thornveld.

Ticks on pastures and on two breeds of cattle in the Eastern Cape province, South Africa

Nyangiwe,Nkululeko; Goni,Sindisile; Hervé-Claude,Louis P.; Ruddat,Inga; Horak,Ivan G.
Fonte: Onderstepoort Journal of Veterinary Research Publicador: Onderstepoort Journal of Veterinary Research
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2011 EN
Relevância na Pesquisa
26.14%
Many studies on the population dynamics of questing ticks on pastures and of parasitic ticks on cattle have been conducted. Few, however, have attempted to link the two in a single study. This study aimed to assess the population dynamics of questing ixodid ticks on pastures and of adult ticks on two breeds of cattle with different levels of susceptibility to tick infestation on the same pastures. Between January 2005 and December 2009 questing ixodid ticks were collected monthly from natural pastures at the Döhne Agricultural Development Institute and at the adjacent Campagna Production System in the Amahlathi District, Eastern Cape province, South Africa. Between February 2007 and January 2010 adult ticks were collected monthly from Bonsmara and Nguni cattle grazing these pastures. Ten tick species were collected from the pastures and 12 from the cattle. Significantly more questing larvae of Rhipicephalus appendiculatus, Rhipicephalus decoloratus, Rhipicephalus evertsi evertsi and Rhipicephalus microplus were recovered from the pastures grazed by Bonsmara cattle than from those grazed by Nguni cattle (p <0.05). Significantly more adult Hyalomma rufipes, Rhipicephalus follis, R. appendiculatus, R. decoloratus, R. evertsi evertsi and R. microplus were collected from the Bonsmara cattle than from the Nguni cattle (p < 0.05). The study showed that Nguni cattle are less susceptible to tick infestation than are Bonsmara cattle and fewer questing ticks are collected from pastures grazed by Nguni cattle than by Bonsmara cattle.

Production response of lambs receiving creep feed while grazing two different pastures

Terblanche,S.; Brand,T.S.; Jordaan,J.W.; van der Walt,J.C.
Fonte: South African Journal of Animal Science Publicador: South African Journal of Animal Science
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2012 EN
Relevância na Pesquisa
35.99%
The aim of the study was to determine the production responses of lambs receiving either creep feed or not while grazing two different pastures. The production of ewes within each treatment was also recorded. The study was conducted at both the Kromme Rhee and Langgewens Research Farms. At Kromme Rhee, sheep grazed kikuyu (Pennisetum clandestinum) pasture under irrigation. Dohne Merino (n = 47) ewes, with their lambs, were randomly allocated to four groups. At Langgewens, the sheep grazed medic (Medicago parrabinga) pastures under dry-land conditions. South African Mutton Merino ewes (n = 89), with their lambs, were randomly divided into four groups. At Langgewens creep feed was provided at 200 g/lamb/day from the start of the study. This was increased by 100 g/lamb/day every week up to a maximum of 600 g/lamb/day. At Kromme Rhee, creep feed was provided at 200 and 300 g/lamb/day for the first and second week, respectively. From week three creep feed was provided ad libitum. At both locations ewes and lambs were weighed once a week. Live weight data of lambs and ewes were analysed by means of a multifactor analysis of variance with treatment (creep feed or no creep feed) and birth status (single and twins) as main factors. Provision a creep feed at Langgewens significantly increased lamb weight...