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Factors Influencing The Yield Proportions Of Plantago Lanceolata L. And Taraxacum Officinale Web. In Lolium Perenne L. Swards, Harald Laser 2021 Justus‐Liebig University, Germany

Factors Influencing The Yield Proportions Of Plantago Lanceolata L. And Taraxacum Officinale Web. In Lolium Perenne L. Swards, Harald Laser

IGC Proceedings (1977-2023)

Diaspores of Plantago lanceolata and Taraxacum officinale respectively were sown in established Lolium perenne swards to determine the dynamics of their yield proportions during five years. The experimental factors were forb species, variety of the grass species (= early or late flowering), N-fertilization, and sward density. The amount of nitrogen fertilizer had the most important effect on yield proportions of the forb species and also on the total dry-matter (= DM) yield. The single creation of gaps in grass swards before sowing forbs had a lasting positive effect on the Plantago lanceolata and Taraxacum officinale proportions. Peak proportions of Taraxacum …


Dynamic Of Native Pasture Influenced By Deferment Of Grazing And Fertilization, K. E. Gomes, G. E. Maraschin, J. Riboldi 2021 EMBRAPA, Brazil

Dynamic Of Native Pasture Influenced By Deferment Of Grazing And Fertilization, K. E. Gomes, G. E. Maraschin, J. Riboldi

IGC Proceedings (1977-2023)

Native pastures of southern Brazil cover 12 million ha and are the main forage feed resource for most domestic livestock. However, their heavy and continuous use has reduced standing biomass and the presence of good forage species, reducing animal performance and jeopardizing the ecosystem sustainability. An alternative for better use of these pastures and their preservation is grazing deferment that allow natural reseeding. The objective of this research was evaluate native pasture dynamic after six years of grazing deferments (GD) periods and soil fertilization effects by point-quadrat method every season. All pasture components were affected by GD, with prostrate grasses …


Evaluation Of Plant Functional Types Response To Grazing And Fertilizer Levels In Natural Grassland, Zélia M. S. Castilhos, V. D. Pillar 2021 Fundação Estadual de Pesquisa Agropecuária, Brazil

Evaluation Of Plant Functional Types Response To Grazing And Fertilizer Levels In Natural Grassland, Zélia M. S. Castilhos, V. D. Pillar

IGC Proceedings (1977-2023)

We report a study on a natural grassland experiment with the objective of finding optimal plant functional types (PFTs) for the description of vegetation response to levels of grazing (ungrazed, grazed) and fertilizer (with, without). The experiment was a split-plot design in randomized blocks, with three replications and the grazing levels in the main plots. Vegetation description was based on species composition and on 12 plant morphology attributes (life-form, growth-form, stem tissue type, leaf cross section, leaf texture, leaf dorsal epidermal surface, leaf ventral epidermal surface, spininess, leaf resistance, leaf width, plant height). Cover-abundance of species was visually estimated. By …


Mountain Pastures Structure And Its Relationship With Grazing, I. Albizu, S. Mendarte, G. Besga, I. Amezaga, M. Onaindia 2021 NEIKER, Spain

Mountain Pastures Structure And Its Relationship With Grazing, I. Albizu, S. Mendarte, G. Besga, I. Amezaga, M. Onaindia

IGC Proceedings (1977-2023)

The present work aims toward an approach to mountain pastures as a system of relationships in which it is needed to point out those environmental factors that reflect more clearly their structure and potential productivity. This initial step of pasture tipification is important as a previous activity before the planning and management of protected areas because these areas support an intensive pastoral activity. In order to achieve this objective a field study was conducted in two areas in the Gorbeia Natural Park (Bizkaia): Arraba and Aldamiñape, located at 900-1100 masl. In each pasture four plots were selected according to orientation …


Structure And Function Vegetation Conditions By Grazing Processes In A Humid Pampean Grassland (Argentina), O. E. Ansín, Estrella M. Oyhamburu, E. A. Hoffmann, M. A. Eirin 2021 Universidad Nacional de La Plata, Argentina

Structure And Function Vegetation Conditions By Grazing Processes In A Humid Pampean Grassland (Argentina), O. E. Ansín, Estrella M. Oyhamburu, E. A. Hoffmann, M. A. Eirin

IGC Proceedings (1977-2023)

Expressed changes were evaluated as consequence of the cattle grazing, or their exclusion, in the structure of plant communities of the Flooding Pampa. We center our interest in the species numbers, plant cover, species diversity and forage availability. The treatments were: a) continuous grazing, b) enclosure grazing and c) controlled grazing. The enclosure grazing area was installed two years before starting the measurements. In the continuous grazing St. Augustine grass (Stenotaphrum secundatum Walt.) holds its initial cover of 64 % and dallis grass (Paspalum dilatatum Poir.) the 15 %. In the enclosure grazing S. secundatum decreased its cover …


Nitrogen Dynamics From Decomposing Litter Of Panicum Maximum With Different Nitrogen And Phosphorus Content In Brazilian Alfissol, R. M. Schunke, J. C. Kiehl, Valdinei T. Paulino, S. Urquiaga, R. M. Bodey, B. Alves 2021 EMBRAPA, Brazil

Nitrogen Dynamics From Decomposing Litter Of Panicum Maximum With Different Nitrogen And Phosphorus Content In Brazilian Alfissol, R. M. Schunke, J. C. Kiehl, Valdinei T. Paulino, S. Urquiaga, R. M. Bodey, B. Alves

IGC Proceedings (1977-2023)

The objective of this study was to measure the dynamics (immobilization and release) of N and to evaluate the effect of the initial chemical composition of four Panicum maximum cultivars grown in a Alfisol and fertilized with different levels of nitrogen (0, 80 e 160 kg ha-1 de N) and phosphorus (0 e 200 kg ha-1), on the release of the N from the litter using the litterbags technique. There was an increase in the litter initial concentration of N with time of decomposition. The Aruana and Vencedor cultivars released about 70 and 60% of N; respectively, …


Impact Of Grazing Management Strategies On Carbon Sequestration In A Semi-Arid Rangeland, Usa, J. D. Reeder, G. E. Schuman, J. A. Morgan, D. R. LeCain, R. H. Hart 2021 U.S. Department of Agriculture

Impact Of Grazing Management Strategies On Carbon Sequestration In A Semi-Arid Rangeland, Usa, J. D. Reeder, G. E. Schuman, J. A. Morgan, D. R. Lecain, R. H. Hart

IGC Proceedings (1977-2023)

The effects of 12 years of grazing management strategies on carbon (C) distribution and sequestration were assessed on a semi-arid mixed-grass prairie in Wyoming, USA. Five grazing treatments were evaluated: non-grazed exclosures; continuous, season-long grazing at a light (22 steer-days ha-1) stocking rate; and, rotationally-deferred, short-duration rotation, and continuous, season-long grazing, all three at a heavy stocking rate (59 steer-days ha-1). Non-grazed exclosures exhibited a large buildup of dead plant material (72% of total aboveground plant matter) and forb biomass represented a large component (35%) of the plant community. Stocking rate, but not grazing strategy, changed …


Contribution Of Dairy Cow Manure To Soil Fertility And Nutrient Redistribution In Pastures, S. R. Aarons, C. R. O'Connor, M. Hall, C. J. P. Gourley 2021 Department of Natural Resources and Environment, Australia

Contribution Of Dairy Cow Manure To Soil Fertility And Nutrient Redistribution In Pastures, S. R. Aarons, C. R. O'Connor, M. Hall, C. J. P. Gourley

IGC Proceedings (1977-2023)

The effects of dairy cow manure on soil fertility were investigated at the site of the long-term phosphorus rate by stocking rate farmlet experiment at the Dairy Research Institute, Ellinbank, in Victoria. Manure increased extractable soil P (Olsen) in the 0 - 5 cm layer after 60 days to 61 mg/kg compared with values of 32 mg/kg in the control soils. Extractable soil K (Colwell) almost doubled under manure pads to 5 cm depth from 642 mg/kg in control soils to 1226 mg/kg in manure treated soils. The effects of grazing management on nutrient redistribution and pasture growth within strip-grazed …


Impact Of Increasing Nitrogen Fertilizer Rates Upon An Irrigated Tanzania Grass Pasture. 1. Dry Matter Yield, F. Queiroz-Neto, G. B. Martha Jr., M. A. Penati, M. Corsi, M. J. T. Menezes 2021 Universidade de São Paulo, Brazil

Impact Of Increasing Nitrogen Fertilizer Rates Upon An Irrigated Tanzania Grass Pasture. 1. Dry Matter Yield, F. Queiroz-Neto, G. B. Martha Jr., M. A. Penati, M. Corsi, M. J. T. Menezes

IGC Proceedings (1977-2023)

An experiment was carried out with irrigated Tanzania grass (Panicum maximum, Jacq.) pasture receiving five nitrogen (N) rates of (0, 30, 60, 90 and 120 kg N ha-¹ cut-¹) during the growing season. N application increased dry matter yield and Tanzania growth rate linearly (P < 0.05). Responses to nitrogen applications were higher in the first two cuts of the growing season than in the last two cuts. The N fertilizer conversion into herbage dry matter was also higher in the beginning of the growing season.


Short-Term Study On 13Carbon Discrimination On Irrigated Tropical Pasture, G. B. Martha Jr., M. Corsi, P. C. O. Trivelin, F. Queiroz-Neto 2021 Universidade de São Paulo, Brazil

Short-Term Study On 13Carbon Discrimination On Irrigated Tropical Pasture, G. B. Martha Jr., M. Corsi, P. C. O. Trivelin, F. Queiroz-Neto

IGC Proceedings (1977-2023)

A better understanding of pasture ecosystem can be obtained through the use of 13C discrimination technique. In this context, an experiment, assigned in a randomized complete block design with four replicates, was conducted to evaluate the Δ 13C (‰) discrimination, nitrogen (N) yield (kg N ha-¹), total nitrogen content (g kg dry matter (DM)-¹) and dry matter yield (kg DM ha-¹) on an irrigated Tanzania grass pasture (Panicum maximum, Jacq.) receiving increasing rates (0, 30, 60, 90 and 120 kg N ha-¹ cut-¹) of N fertilizer during the summer. Dry matter yield, N yield and nitrogen …


Apparent Recovery Of Surface Applied Nitrogen Fertilizer By A Coastcross Pasture, A. C. Primavesi, O. Primavesi, L. A. Corrêa, H. Cantarella, A. G. Silva 2021 EMBRAPA, Brazil

Apparent Recovery Of Surface Applied Nitrogen Fertilizer By A Coastcross Pasture, A. C. Primavesi, O. Primavesi, L. A. Corrêa, H. Cantarella, A. G. Silva

IGC Proceedings (1977-2023)

Nitrogen recoveries from five levels of urea and ammonium nitrate surface-applied on coastcross pasture, grown on a dark red latosol (Hapludox), in São Carlos, SP, Brazil, under tropical altitude climate, were estimated. Significant differences occurred within periods (P < 0.05), depending on climatic conditions. Under adequate plant growth conditions, mean N recovery from urea was about 67%, sometimes reaching 80%, of that from ammonium nitrate. Recovery of ammonium nitrate varied from 45 to 68% of applied N.


Soil Ph Correction Affecting N-Use Efficiency Of Urea By Brachiaria Brizantha Cv. Marandu Pastures, P. P. A. Oliveira, P. C. O. Trivelin, W. S. Oliveira, G. M. Teixeira, M. Corsi 2021 Universidade de São Paulo, Brazil

Soil Ph Correction Affecting N-Use Efficiency Of Urea By Brachiaria Brizantha Cv. Marandu Pastures, P. P. A. Oliveira, P. C. O. Trivelin, W. S. Oliveira, G. M. Teixeira, M. Corsi

IGC Proceedings (1977-2023)

Nitrogen fertilization is one of the largest investment when recovering and intensifying pasture management. Urea nitrogen use efficiency was studied in Brachiaria brizantha pasture under tropical conditions where liming was applied to the soil in two dates ("early" and "late" - March and August, respectively). Lime was broadcasted and urea was either broadcasted or subsurface-band applied. "Early" applied lime caused 16,4% increase in forage dry matter yield in the rainy season. Urea-N recovered in the shoots was higher when subsurface band applied independently from time of lime application.


Evaluation Of “Feeding Intelligence” In Murrah Water Buffaloes Grazing Three Different Tropical Grasses, P. B. Alcântara 2021 Instituto de Zootecnia, Brazil

Evaluation Of “Feeding Intelligence” In Murrah Water Buffaloes Grazing Three Different Tropical Grasses, P. B. Alcântara

IGC Proceedings (1977-2023)

Acceptability and palatability are two terms of large utilization that help to understand animal selection for feed. “Feeding intelligence” is a new theory recently introduced to replace those terms mentioned before. According to most recent research works, the feeding intelligence is acquired and remains for a long period of time in the memory of some animals. The present experiment had the purpose of showing its occurence in water buffaloes aiming, at the same time, to better understand their feeding behaviour. Three tropical grasses were tested: Brachiaria brizantha cv Marandu, Panicum maximum cv Tanzania and Setaria sphacelata var. sericeae cv Kazungula. …


Foraging Strategies On Rangeland: Effects On Intake And Animal Performance, Peter O’Reagain 2021 Department of Primary Industries, Australia

Foraging Strategies On Rangeland: Effects On Intake And Animal Performance, Peter O’Reagain

IGC Proceedings (1977-2023)

Rangelands exhibit extreme spatial and temporal variability in forage quality and availability. The animals that utilise these rangelands have consequently evolved a range of foraging strategies in an attempt to cope with this variability and maintain nutrient intake. In general, animals respond to and exploit spatial variability at all scales by selecting those items or units which optimise the intake of digestible nutrients and hence animal production. Animals similarly employ a variety of strategies to cope with temporal variability on rangelands. These strategies may include adjusting foraging behaviour and/or exploiting critical resources or resource areas to buffer temporal variability in …


On The Scale Dependence Of Foraging In Terrestrial Herbivores, John M. Fryxell, C. B. D. Fortin, J. Wilmshurst 2021 University of Guelph, Canada

On The Scale Dependence Of Foraging In Terrestrial Herbivores, John M. Fryxell, C. B. D. Fortin, J. Wilmshurst

IGC Proceedings (1977-2023)

Meaningful modeling of the spatial and trophic dynamics of terrestrial herbivores demands understanding of the constraints and fitness objectives that presumably underlie behavior. This is complex in terrestrial herbivores, because of scale-dependent constraints on nutrient or energy gain. Mechanistic processes of forage cropping, forage mastication, movements between feeding stations, and forage digestion each have unique constraints that apply on different time, size, and spatial scales. Moreover, competing activities are rarely taken into account. Experimental testing of foraging objectives is therefore clouded by uncertainty regarding which time scale is most relevant from the animal’s perspective, leading to confusion and misrepresentation in …


Influence Of Sward Height, Concentrate Supplementation And Season On Grazing Activity Of Beef Cows, O. J. Gekara, E. C. Prigge, W. B. Bryan, M. Schettini, E. L. Nestor 2021 West Virginia University

Influence Of Sward Height, Concentrate Supplementation And Season On Grazing Activity Of Beef Cows, O. J. Gekara, E. C. Prigge, W. B. Bryan, M. Schettini, E. L. Nestor

IGC Proceedings (1977-2023)

The influence of sward height, concentrate supplementation and season on daily pattern of forage consumption of lactating beef cows grazing cool season pastures was determined. Cows (n=24; BW=535±10.8 kg) were randomly assigned to eight plots maintained at sward heights (SH) of either 4-8 cm or 8-12 cm and fed three levels of concentrate supplement: none = 0 kg/day, low = 3.12 kg/day or high = 6.24 kg/day. Cows on lower SH had greater (P < .08) forage dry matter intake and spent an additional 1.2 hours/day (P < .01) grazing compared to the higher SH. Cows on lower SH consumed 7.7 kg/day of forage dry matter and grazed 9.4 hours/day whereas those on higher SH consumed 7.1 kg/day and grazed 8.2 hours/day. Cows on lower SH grazed 0.7 hours/day (P < .06) and 0.4 hours/day (P < .08) longer at 06:00-10:00 hour and 11:00-13:00 hour, respectively, compared to the higher SH. Grazing efficiency (kg of forage consumed/hour of grazing) decreased (P < .01) as season progressed. Season influenced duration of grazing activity (P < .01). Cows grazed 0.5 hours longer (P < .01) at 06:00-10:00 hour late in summer (August) compared to spring (May) and mid summer (June/July). Cows grazed 0.3 hours longer (P < .08) at 11:00-13:00 hour during spring compared to late summer.


Safflower (Carthamus Tintorius): A Promising Forage Crop For Semi-Arid Regions, Y. Leshem, I. Bruckental, S. Y. Landau, G. Ashbell, Z. Weinberg 2021 Agricultural Research Organization, Israel

Safflower (Carthamus Tintorius): A Promising Forage Crop For Semi-Arid Regions, Y. Leshem, I. Bruckental, S. Y. Landau, G. Ashbell, Z. Weinberg

IGC Proceedings (1977-2023)

The yield, quality, preservation and intake of safflower hay were determined in two successive years - 1998 and 1999. Field experiments carried out at the Bet Dagan experimental station on the coastal plain of Israel under rain-fed conditions. A spineless variety was tested under three sowing dates. Yield decreased and quality improved as the sowing date receded from November 12 to February 3. Respective yields, IVDMD and CP content were: 22 and 8 ton DM/ha, 48.9% and 65.5% , 10.0% and 14.6%. Safflower at 290, 410 and 770 g/kg DM was ensiled in 1.5-l anaerobic glass jars with or without …


Effects Of Different Levels Of Energy On Growth Of Grazing And Drylot Fed Holstein Heifers, L. P. Novaes, C. E. Polan 2021 EMBRAPA, Brazil

Effects Of Different Levels Of Energy On Growth Of Grazing And Drylot Fed Holstein Heifers, L. P. Novaes, C. E. Polan

IGC Proceedings (1977-2023)

Growth of Holstein heifers were studied to evaluate the combination of a drylot phase followed by feeding energy for pasture supplementation during the grazing season of 1988. Heifers grazed a grass-legume mixture in six paddocks of 1.5 ha each. After drylot, animals were equally allotted to pasture and none or 2.0 kg/d of corn were fed in addition to grazing in a changeover design with repeated measurements. Heifers were fed a high (HE) or low energy (LE) diets in confinement and daily gains were 1190 (HE) and 990 g/day (LE) which were different. On pasture, corn supplementation did not enhance …


Leaf Fragment Identification Of Subtropical Native Grass Species, C. H. E. C. Poli, J. M. Rosito, A. G. Schirmer, P. R. Boggiano, P. C. de F. Carvalho 2021 Universidade Federal do Rio Grande do Sul, Brazil

Leaf Fragment Identification Of Subtropical Native Grass Species, C. H. E. C. Poli, J. M. Rosito, A. G. Schirmer, P. R. Boggiano, P. C. De F. Carvalho

IGC Proceedings (1977-2023)

The present study was carried out to characterise leaf fragments of important plant species of a subtropical native sward in the southernmost state of Brazil. Thirteen important grass species were collected from April to May 1999. Both sides of the leaves were observed using a stereomicroscope. In addition, two approaches were tested to provide a clearer characterisation of the leaves of each species: the leaves were either dried or frozen. The kind and number of veins, the kind and number of hair, and the arrangements and number of stomates on both sides of each leaf are the most useful characteristics …


Effect Of Soil Ph On Emergence And Survival Of Austrodanthonia Spp., M. A. Islam, P. M. Dowling, B. C. Jacobs, P. J. Milham, D. L. Garden, M. K. Conyers, R. van de Ven 2021 NSW Agriculture, Australia

Effect Of Soil Ph On Emergence And Survival Of Austrodanthonia Spp., M. A. Islam, P. M. Dowling, B. C. Jacobs, P. J. Milham, D. L. Garden, M. K. Conyers, R. Van De Ven

IGC Proceedings (1977-2023)

We evaluated the effects of soil acidity on seedling emergence and seedling persistence of several ecotypes of Austrodanthonia spp. collected from the Central, Southern and Monaro Tablelands of New South Wales (NSW) in southern temperate Australia. A pot experiment was conducted outdoors to identify the most promising material tolerant to soil acidity for domestication. In the experiment, 183 ecotypes and two commercial cultivars of Austrodanthonia were grown in pots at three levels of pHCa (3.9, 4.4 and 5.3). The pH treatments were achieved by adding either aluminium sulphate or lime to an acid earthy sandy loam soil collected from …


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