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- Grazing (333)
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- Sheep (135)
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- Crude protein (78)
- Grass (78)
- White clover (78)
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- Rangelands (76)
- Tall fescue (75)
- Lolium perenne (73)
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Articles 241 - 270 of 7001
Full-Text Articles in Physical Sciences and Mathematics
Selection For Improved Low Temperature Germination Of White Clover Seed, J R. Caradus
Selection For Improved Low Temperature Germination Of White Clover Seed, J R. Caradus
IGC Proceedings (1993-2023)
Selections were made within 10 cultivars of white clover (Trifolium repens L.) for rapid germination rale al 4°C. There were 2 selection cycles and progeny from crosses between genotypes selected from within cultivars were compared wilh the original unselected cultivar seed lines for ability to germinate at 4°C. There ·was significant variation among control cultivars and among selected lines for germination rate index at 4°C. Cultivars from northern Europe had a higher germination rate index than cultivars from New Zealand, Australia and Israel. Selection for increased germination rate index at 4°C was successful and the relationship between germination rate …
Effects Of Grassland Burning During Early Spring In Korea, Sung Seo
Effects Of Grassland Burning During Early Spring In Korea, Sung Seo
IGC Proceedings (1993-2023)
A field experiment was carried out in 1989 and 1990 to determine the effects of dead material (length 15 cm and 30 cm), date of burning (21 February, 2 March, I I March and 20 March) and a non-burning control treatment during eacly spring on grass growth, yield, and nutritive value in existing pasture dominated by orchardgrass (Dactylis glomerata L.). On average burning treatments increased the soil surface temperature and the 10 cm soil depth temperature by S.5°C and 2.8°C respectively. A little burning damage was present after the burn on 20 March. However, burning, date of burning or …
Factors Required To Sustain Pastoral Farming Systems And Forage Supply In Winter Cold Zones, H T. Kunelius, D A. Kim, H Hirota, T Zhu
Factors Required To Sustain Pastoral Farming Systems And Forage Supply In Winter Cold Zones, H T. Kunelius, D A. Kim, H Hirota, T Zhu
IGC Proceedings (1993-2023)
Forage grasses and legumes are a main component of livestock diets in winter cold zones, There are over 130 million ha of grassland in this zone and there is a large, undeveloped land base in fringe areas suitable for forage production. Regulations on land ownership and use hamper efficient development of forage-based farming systems in some regions. The short growing season Ii mils the grassland farming in the winter cold zones. The winter season is long and cold temperatures, freezing and thawing, and diseases' exert severe stress on overwintering forage plants. The development of persistent cultivars is essential for sustained …
Rangeland Exploitation- The Global Need For Integrated Science, A H. Nordmeyer
Rangeland Exploitation- The Global Need For Integrated Science, A H. Nordmeyer
IGC Proceedings (1993-2023)
The global surge in human population growth is placing major pressures on winter cold rangelands. The need is urgent to develop an international science that comes to grips with local requirements for food and fuel, and combines these with the global requirements of maintaining and increasing stores of carbon. The critical problem for rangelands is that most systems do not generate incomes to allow replacement or enhancement of the nutrients removed by herded animals, by cut-and-carry forage harvesting, and by fuel extraction. Progress in rangeland science that is relevant to subsistence cultures requires a better understanding of the carbon and …
Sustainable Clover-Dominant Swards For Lamb Production Under Low Temperatures, J E. Vipond, G Swift, T H. Mcclelland
Sustainable Clover-Dominant Swards For Lamb Production Under Low Temperatures, J E. Vipond, G Swift, T H. Mcclelland
IGC Proceedings (1993-2023)
ABSTRACT Upland pastures for sheep and beef cattle in the UK typically contain less than 5% clover in the grazed herbage, Use of fertiliser N, low P and K status, low pH and inappropriate choice of grass and clover varieties are implicated in this low pasture clover content, along with temperature constraints. In a 4-year study, swards of tecraploid perenn ial ryegrass (Lolium perenne, cv. Condesa) were compared with swards of a diploid perennial rye grass (cv. Contender) both being maintained at a constant grazing height of 4-6 cm and given 160 kg N/ha/year. Lamb output (kg/ ha) from …
Effect Of Condensed-Tannins In Lotus Pedunculatus On The Digestion And Plasma Metabolism Of Methionine And Cystine In Sheep, W C. Mcnabb, G C. Waghorn, T N. Barry, I D. Shelton
Effect Of Condensed-Tannins In Lotus Pedunculatus On The Digestion And Plasma Metabolism Of Methionine And Cystine In Sheep, W C. Mcnabb, G C. Waghorn, T N. Barry, I D. Shelton
IGC Proceedings (1993-2023)
The effect of condensed tannins (CT) on the digestion and metabolism of methionine and cystine was studied in sheep housed indoors and fed Lotus pedunculatus hourly. The PBO sheep (no CT) lost 30% of ingested methionine and cystine across the rumen, whereas the control sheep (CT acting normally) lost no methionine and cystine across the rumen. The apparent absorption of methionine from the small intestine was 27% higher in control than PBO sheep, but both groups had a similar apparent absorption of cystine from the small intestine. CT had no effect upon plasma methionine irreversible loss rate (IRL), but markedly …
Stockpiling Of Tropical Forage For The Dry Season In Martinique, I Gayalin
Stockpiling Of Tropical Forage For The Dry Season In Martinique, I Gayalin
IGC Proceedings (1993-2023)
In Martinique standing fodder crops were found to be an alternative way to improve dry season feeding to livestock. The stockpiling ability of 4 grasses (Tripsacum laxum, Pennisetum purpureum, • Brachiaria decumbens and Panicum maximum) has been tested for 2 years on 3 sites located in different pedoclimatic zones. Two deferment 1 dates were chosen (1 and: 2 months before the end of the rainy season). During the dry season, from February-June, dry matter (DM). yields and morphological composition (green leaves, stems and dead' materials) were estimated through sampling every fortnight. In the· drier site, accumulated DM yields and …
Breeding Of Apomictic Brachiaria Through Interspecific Hybridisation, C B. Do Valle, C Gilenke, G.O C. Leguizamon
Breeding Of Apomictic Brachiaria Through Interspecific Hybridisation, C B. Do Valle, C Gilenke, G.O C. Leguizamon
IGC Proceedings (1993-2023)
Brachiaria is a tropical grass genus recently introduced on the American continent. Two species are widely sown as pastures in Brazil, n. decumbens (D) cv. Basilisk, and n. brizantha (B) cv. Marandu. These 2 cultivars behave as obligate apomicts (APO), therefore impairing direct hybridisation. A breeding programme was started al the National Center for Research in Beef Callie (CNPGCEMBRAPA), Campo Grande, MS, Brazil in 1988, with the objeclive of obtaining apomictic hybrids with the growth habit and adaptation lo poor soils of D, resistance lo spilllebugs (Homoplera:Cercopidae) of B using sexual B. mzil:iensis (R) as mother plant. R has …
Modelling As Tool For Grassland Science Progress, N G. Seligman
Modelling As Tool For Grassland Science Progress, N G. Seligman
IGC Proceedings (1993-2023)
Simulation modeling in grassland science has a history of more than 20 years. To dnle it has been distinguished more by its continuing and expanding development than by its success in advancing grassland science and practice. This possibly reflects the phenomenal increase in computer technology compared with the much more modest progress in grassland science. Models have nevertheless been the vehicle for identifiable contributions to grassland theory and there are an increasing number of successful applications in management and policy situations. Expectations for future contributions are more realistic today than in the heady early years, but despite much disillusion, the …
Decision Support System In The Transfer Of Grassland Technology, J W. Stuth, W T. Hamilton, J C. Conner, D P. Sheehy
Decision Support System In The Transfer Of Grassland Technology, J W. Stuth, W T. Hamilton, J C. Conner, D P. Sheehy
IGC Proceedings (1993-2023)
A world-wide demand for sustainable development of our grazinglands has placed an unprecedented urgency to determine mechanisms to develop and transfer technology that meets the needs of individual landholders and overarching values of society. Unfortunately, advances in science and technology have outstripped our ability lo organise information into a usable form using traditional institutions. The emergence of computer technology with high power/ cost ratios has accelerated interest in computerised decision support systems (DSS) over the past 10 years. These systems assist resource managers in dealing with complex planning problems by allowing exploration of alternatives and selection of appropriate technology. If …
Software For Grassland Management For The Supply Of Fresh Feed For Stall-Feeding And/Or Grazing And For Conservation In Combination With Feed Production On Arable Land, A Chudy
IGC Proceedings (1993-2023)
Tasks, fundamentals and methodics (algorithms) of software for the projection of feed production (FUPRO) as part of an integrated software program (the package Futterplanung), are described. It covers total feed-economic relations, starting from the use of agricultural acreage up to specific animal requirement.
Sward Production Estimated By Spectral Reflectance, G Nagy, V Zilinyi
Sward Production Estimated By Spectral Reflectance, G Nagy, V Zilinyi
IGC Proceedings (1993-2023)
A non-destructive spectral reflectance method was used for the measurement of aerial biomass yields of different grasslands. Vegetation indices {VI) were calculated from the green, red and near-infrared light reflectance. These indices were compared with actual grass yields cut just after the reflectance measurement. The correlation coefficient between actual yields and VI was significant (r=0.969,n=24). This non-destructive technique is therefore a reliable tool for the estimation of standing biomass of grasslands.
Inference Space Choices In Combined Mixed Model Analyses Of Discrete Grazing Trials, H A. Fribourg, R W. Thompson, J C. Waller, W L. Sanders
Inference Space Choices In Combined Mixed Model Analyses Of Discrete Grazing Trials, H A. Fribourg, R W. Thompson, J C. Waller, W L. Sanders
IGC Proceedings (1993-2023)
Grazing trials are limited by financial and logistical constraints that restrict duration and number of treatments to be investigated. Combining data from independent trials may be a feasible way to circumvent these constraints and provide a more meaningful body of information. Datasets were pooled from 12 independent trials conducted during the last 13 springs at 9 locations in 7 USA eastern states (a total of 37 location/ years) to provide combined estimates of steer (Bos taurus) performance on Festuca arundinacea pastures free of or infested with the endophytic fungus Acrenoium coenophialium, and to demonstrate the effectiveness and …
An Expert System To Advise Tasmanian Farmers On Pasture Mixtures And Fodder Crops, Peter Gillard
An Expert System To Advise Tasmanian Farmers On Pasture Mixtures And Fodder Crops, Peter Gillard
IGC Proceedings (1993-2023)
In Tasmania, the Department of Primary Industry and Fisheries needed to find a more effective method of informing farmers obout the best pasture and forage species. PASTURBPAK, an expert system, was designed to meet this need. The program offers advice on mixtures of species and lists cultivars that are adapted to the environment, and the need of the farmer and livestock type. Seed merchants have installed the software to make the information available when farmers buy seed. Sales starf can now instantly access the corporate expertise of DPIF, and offer customers printed advice specific to their need. The relevance of …
Comparison Of Two Calibration Procedures For Predicting Leaf Percentages From Forage Sorghums And Pearlmillets Using Near-Infrared Reflectance Spectroscopy, T P. Karnezos, A G. Matches, J W. Keeling
Comparison Of Two Calibration Procedures For Predicting Leaf Percentages From Forage Sorghums And Pearlmillets Using Near-Infrared Reflectance Spectroscopy, T P. Karnezos, A G. Matches, J W. Keeling
IGC Proceedings (1993-2023)
A rapid method for determining leaf percentage (LP) from forage sorghums (Sorglium bicolor (L.) Moench) and pearlmillets (Pennisetum americaum (L.) Leeke) is reported. Our objective was to develop and compare two near-infrared reflectance spectroscopy (NIRS) calibration methods for predicting LP. Calibration methods developed were: I) leaves assigned a value of 99.99% leaf and 0.01 % stem, and stems a value of 99.99% stem and 0.01% leaf; and 2) ground leaf and stem samples mixed by weight to obtain a range of LP. Samples were scanned using NIRS and calibration equations developed. Equations had coefficients of multiple determination (R2) …
Computer Simulation To Aid The Development, Transfer An Adoption Of Alternative Forage Conservation Systems, C A. Rotz, D R. Buckmaster
Computer Simulation To Aid The Development, Transfer An Adoption Of Alternative Forage Conservation Systems, C A. Rotz, D R. Buckmaster
IGC Proceedings (1993-2023)
A computer simulation model of forage production, conservation and use was developed to evaluate forage technologies. The model simulates forage losses and quality changes along with the use and costs of machines, structures, labour, fuel, chemicals, etc. Alfalfa and corn produced on the farm arc supplemented with purchased feeds to feed a dairy herd or they are sold. Simulation over many years of weather conditions provides a long-term evaluation of the performance and economics of alternative forage systems. Simulation results provide manufacturers with design-performance constraints which aid the development of new products. Adoption of available forage technology is aided by …
Developing Long-Term Weather Records For Use With Rangeland Management Modelsc, Clayton L. Hanson, J Ross Wight
Developing Long-Term Weather Records For Use With Rangeland Management Modelsc, Clayton L. Hanson, J Ross Wight
IGC Proceedings (1993-2023)
The use of natural resource models for research and management of rangeland ecosystems is limited by the unavailability of long-term weather records. This paper identifies sources of weather information for the United States; suggests methods for estimating missing records; and illustrates the use of double-mass curve procedures for evaluating the quality of data sets. Where weather data are limited in ducat ion or unavailable, stochastic weather generation is an option to simulate daily weather records.
Making Models Easy To Use, J Ross Wight, Clayton L. Hanson
Making Models Easy To Use, J Ross Wight, Clayton L. Hanson
IGC Proceedings (1993-2023)
A major limitation to the application of natural resource models to resource management problems is the unavailability of input information and complexity of model operation and output interpretation. These problems can be moderated by using synthetic weather data, algorithms and expert systems to calculate model parameters and input variables and computer programs to simplify development of input data files and interpretation of output results. This paper summarises some of the procedures and techniques that can be used to make models easier to use and more useful as management tools.
Simulation Models As Decision Aids For Management Of Rangeland Ecosystems, J Ross Wight, Clayton L. Hanson
Simulation Models As Decision Aids For Management Of Rangeland Ecosystems, J Ross Wight, Clayton L. Hanson
IGC Proceedings (1993-2023)
Rangeland simulation models have been used primarily as research tools to synthesise and organise information and to conceptualise and describe the interacting components of the ecosystem. Their application as decision aids for range management has not been developed. This paper discusses ways simulation models, such as SPUR· (Simulation of Production and Utilisation of Rangelands), can be used to forecast herbage p1oduction and the occurrence of biological windows, enhance monitoring, and predict the impacts of management and climate change on the soil, water, and plant resources including species composition.
Models Of Pasture Production To Aid On-Farm Decision Making In New Zealand, J A. Baars, M D. Rollo
Models Of Pasture Production To Aid On-Farm Decision Making In New Zealand, J A. Baars, M D. Rollo
IGC Proceedings (1993-2023)
Two microcomputer-based predictive pasture models, for use in decision making by agricultural consultants and industry, are described. The first model (GRASS) was developed to understand the interactions between environment and management. The second model supplies pasture growth rates for current or predicted weather conditions by adjustment of stored actual average fortnightly pasture growth rates for a wide range of measurement sites. Ways are described in which the models are being used in transfer of technology.
Production Of Dryland Lucerne In The Western And Southern Cape Regions Of South Africa, J M. Van Heerden
Production Of Dryland Lucerne In The Western And Southern Cape Regions Of South Africa, J M. Van Heerden
IGC Proceedings (1993-2023)
Cutting trials were conducted with lucerne (Medicago sativa) cv. S A Standard under dryland conditions over a period of 8 (1982 to 1989) years at 2 sites, one each in the western (Elsenburg) and southern (Tygerhoek) Cape. The sites differed in soil type and rainfall distribution. Replicated plots were harvested at 3 set frequencies (4·, 6- and 8- weekly). Production was lowest during summer and highest in late spring and increased with decreased harvesting frequency at both sites. These data were used to derive equations for the extrapolation of the seasonal yield. Inputs into the model 11cc average …
Graze Model: Importance Of Simulating Conceptual Grazing Areas Within A Paddock, Otto J. Loewer, L D. Parsch, H D. Scott, C P. West, A L. Goetsch
Graze Model: Importance Of Simulating Conceptual Grazing Areas Within A Paddock, Otto J. Loewer, L D. Parsch, H D. Scott, C P. West, A L. Goetsch
IGC Proceedings (1993-2023)
The selective grazing logic within the computer simulation model GRAZE was tested to determine if predicted ·results differed appreciably from situations ·where non-selective grazing logic· was used. Results indicated that predictions would_ differ somewhat." The main cause of the differences was determined to be the simulated levels of plant dry matter availability, which were considerably higher when non-selective· grazing was used.
Development Of An Expert System For New Zealand Seasonal-Supply Dairy Farmers, D I. Gray, G A. Lynch, E G. Todd, J C. Lockhart, W J. Parker
Development Of An Expert System For New Zealand Seasonal-Supply Dairy Farmers, D I. Gray, G A. Lynch, E G. Todd, J C. Lockhart, W J. Parker
IGC Proceedings (1993-2023)
The mechod for developing an expert system for the drying-off decision on seasonal-supply dairy farms is described. The decision-making process ' of 4 expert seasonal-supply dairy farmers and the consultancy process used by 2 New Zealand Dairy Board Consulting Officers were identified in a series e>f interviews. This information ,was used to develop 2 models; one of expertise and the other of user requirements. These models form the basis of an expert system to improve the decision-making ability of. New Zealand seasonal-supply dairy farmers.
Rehabilitation On Public Rangelands In Idaho, Usa: A Change In Emphasis From Grass Monocultures, Mike Pellant, Stephen B. Monsen
Rehabilitation On Public Rangelands In Idaho, Usa: A Change In Emphasis From Grass Monocultures, Mike Pellant, Stephen B. Monsen
IGC Proceedings (1993-2023)
Since the 1940s the Bureau of Land Management has reseeded 485 830 ha of public rangelands in southern Idaho. Introduced wheatgrasses were seeded on most rehabilitation projects, often resulting in monoculture plant communities. Introduced wheatgrasses were relatively inexpensive to seed, established well, excluded weedy annuals and provided additional livestock forage. Concern about extensive shrubland losses after wildfires prompted BLM managers to begin reseeding native shrubs in the early 1980s. Use of different herbaceous plants on rehabilitation projects is increasing. Seed mixtures now include up to 10 species (grass, forb and shrubs) that, when established, meet multiple use resource objectives.
Micro-Computer Version Of The Database On Feed Commodities Derived From Pastures And Green Crops, H T. Ostrowski-Meissner
Micro-Computer Version Of The Database On Feed Commodities Derived From Pastures And Green Crops, H T. Ostrowski-Meissner
IGC Proceedings (1993-2023)
The subunit of the national feed database devoted specifically to feeds derived from grasslands and green crops is presented. This collection of chemical and nutritional data is the result of 20 years of data collection from analyses conducted from 62 laboratories Australia-wide, The data entries are classified according to each Australian state and laboratory which provided the analytical and nutritional characteristics of fodder. Each entry is classified according to the International Feed Numbering (IFN) system as maintained by the International Network of Feed Information Centres (INFIC), The data in the collection as presented in the paper are an integral part …
A Computer Model For Determining When To Start Spring Grazing, Dennis R. Buckmaster, Warren J. Parker
A Computer Model For Determining When To Start Spring Grazing, Dennis R. Buckmaster, Warren J. Parker
IGC Proceedings (1993-2023)
A simple computer model is presented for determining the earliest grazing date after winter freezing. The model also illustrates principles of rotational grazing management and projects when forage should be conserved during the spring. Inputs to the model include initial herbage cover, herbage growth rate, herbage quality, a post•grazing residual dry matter target, a harvest set•aside threshold, and a description of the grazing animals.
Comparison Of Methods For Assessing Productivity Of Native Pastures In Queensland, K A. Day, G M. Mckeon, D M. Orr
Comparison Of Methods For Assessing Productivity Of Native Pastures In Queensland, K A. Day, G M. Mckeon, D M. Orr
IGC Proceedings (1993-2023)
The relationship between seasonal climatic conditions and observed seasonal pasture growth was examined for 3 native pasture sites in south-east Queensland for periods of up to 5 years. Nine indices of seasonal climatic conditions were considered. Across sites, between year differences in observed growth were best accounted for by the average daily ratio of calculated transpiration and vapour pressure deficit, This index accounted for 83% of the between year variation in observed growl h.
Application Of Neural Networks To The Extraction Of Various Types Of Grasslands In Japan Using Landsat Thematic Mapper Data, Mikinori Tsuiki, Shigeo Takahashi, Toshiki Oku
Application Of Neural Networks To The Extraction Of Various Types Of Grasslands In Japan Using Landsat Thematic Mapper Data, Mikinori Tsuiki, Shigeo Takahashi, Toshiki Oku
IGC Proceedings (1993-2023)
A neural network was applied to the extraction of various types of grasslands using Landsat Thematic Mapper (TM) data. Training fields contained 12 classes (water, paddy field, farmland, sands and rocks, urban area, coniferous forest, deciduous forest, golf course, Sasatype grassland, Miscanthus type grassland, meadow before culling and meadow after cutting). Classification performance using the neural network was 99.4%, which was 2.4% higher than that obtained using the maximum likelihood method. For all types of grasslands, classification performance was 99.8%. The results of the classification area obtained using the neural network and the maximum likelihood method resembled each other. …
Use Of A Simple Model Of Continuous And Rotational Grazing To Compare Herbage Consumption, Simon J.R Woodward, G `C Wake, D G. Mccall, A B. Pleasants
Use Of A Simple Model Of Continuous And Rotational Grazing To Compare Herbage Consumption, Simon J.R Woodward, G `C Wake, D G. Mccall, A B. Pleasants
IGC Proceedings (1993-2023)
A simple mathematical model (a linear dynamical system) was constructed to predict herbage consumption by grazing animals. This model was used to compare 3 grazing methods over a range of stocking rates at low pasture mass. The grazing methods compared were: continuous grazing (CTS), rotational grazing with equal time intervals (BQ), and rotational grazing where the time of shift was optimal for maximising intake (OPT). The rotational methods were the simplest possible, the land being subdivided into 2 fields, each of which was grazed once. The order of grazing the fields was also considered. The model predicts (I) that at …
Pasture Plant Identification In The Western Queensland Arid Zone, J A. Milson, I F. Beale, J A. Reynolds, J J. Bushwell, D Phelps
Pasture Plant Identification In The Western Queensland Arid Zone, J A. Milson, I F. Beale, J A. Reynolds, J J. Bushwell, D Phelps
IGC Proceedings (1993-2023)
Since plant species composition is an important indicator of the health or condition of pastures and therefore the land, a first step for graziers interested in conserving the total range resource is to understand vegetation species and thus be able to identify them and to recognise species changes. This project is aimed at producing and distributing colour leaflets of the major native and problem plant species (including woody weeds) in the four major community types in western Queensland. The number of colour leaflels for the series totals 60. The number of species represented is about 230. These leaflets are dislributed …