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Articles 1 - 18 of 18
Full-Text Articles in Physical Sciences and Mathematics
Developing A Tall Fescue For Reduced Grass Tetany Risk, H F. Mayland, D A. Sleper
Developing A Tall Fescue For Reduced Grass Tetany Risk, H F. Mayland, D A. Sleper
IGC Proceedings (1993-2023)
Tall fescue (Festuca arundinacea Schreb,) is an important forage grass, and like other C3 grasses, has the potential to cause grass tetany in grazing ruminants. Genetic variation in cation uptake by fescue was exploited by selecting for high Mg and Ca relative to K CQncenlration in fescue, The grass tetany ratio, K/(Ca+Mg), was reduced about 18% after 2 selection cycles. The mean Mg and K/(Ca+Mg) values for 20 C1 plants, grown at pH 6.4, were weakly related (r2-0.42 and 0.48) to those of plants grown in calcareous soil pH 8.2. The P, Na, Mn, Fe, Cu, and Zn concentrations …
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 …
Ruminant Animal Production From Forages: Present Position And Future Opportunities, David E. Beever
Ruminant Animal Production From Forages: Present Position And Future Opportunities, David E. Beever
IGC Proceedings (1993-2023)
The utilisation of forages by ruminants for the synthesis of meat and milk is often below expectations both in terms of the quantity and the composition of the product. Recognising that the nutrition of the ruminant is complicated by the need to meet the requirements of the host animal and its rumen ecosystem, it is now possible to identify the causes of some of these inefficiencies and to develop suitable strntegies to overcome them. This paper attempts, through a review of the mechanisms of carbohydrate and protein utilisation in the rumen and in the animal tissues, and identification of the …
Investigations On Energetic Utilization Of A Range Of Fresh, Dried And Ensiled Forages By Wether Sheep, W Jentsch
IGC Proceedings (1993-2023)
The energy utilisation of 29-38 fresh (frozen), dried and ensiled forages was measured In respiration calorimeters with adult wether sheep. Forages were fed alone and in combination with cereals. There were no differences in energetic feed values (digestible and metabolizable energy , as well as efficiency of energy deposition) between fresh and dried forages, Feeding values of silages fed as a sole diet tend to be lower than those of all other rations; the efficiency of energy deposition was on an average 4.2% less than the predicted values.
Formation And Development Of The Center For Grassland Studies At The University Of Nebraska, M A. Massengale
Formation And Development Of The Center For Grassland Studies At The University Of Nebraska, M A. Massengale
IGC Proceedings (1993-2023)
The Center for Grassland Studies was formed at the University of Nebraska in 1994 to implement focused interdisciplinary research, educational, and service programs and activities that emphasize the role of grasslands as a natural resource and conservation measure and that enhance the efficiency, profitability, sustainability, and aesthetic value of grasslands, wetlands, and turf. Although the Center is still in a developmental stage, it appears to be accomplishing those objectives.
Tropical Forage Seed Production In Southeast Asia: Current Status And Prospects, C Phaikaew, L Guodao, A Abdullah, M Tuhulele, E Magboo, B Bouahom, W Stur
Tropical Forage Seed Production In Southeast Asia: Current Status And Prospects, C Phaikaew, L Guodao, A Abdullah, M Tuhulele, E Magboo, B Bouahom, W Stur
IGC Proceedings (1993-2023)
The demand for forage seed in southeast Asia has increased in recent years. More than 1,200 tons of seed were produced in Thailand in 1995 with smaller quantities of seed having been produced in China, Lao PDR, Malaysia, Philippines and Indonesia. Large quantities have been produced of Brachiaria ruziziensis, Stylosanthes hamata, Stylosanthes guianensis and Panicum maximum. There are good prospects to increase forage seed production and to develop trade between countries in the southeast Asian region. There is a need to increase seed production of widely adapted species, and expand production of forages for other purposes such as turf …
Development Of Forage Components Through Farmer Participatory Research, F G. Gabunada Jr, W W. Stur, P M. Horne
Development Of Forage Components Through Farmer Participatory Research, F G. Gabunada Jr, W W. Stur, P M. Horne
IGC Proceedings (1993-2023)
This paper describes farmer participatory research activities aimed at developing appropriate forage technologies with smallholders in Southeast Asia. Farmers are actively involved from the early stages, working as equal partners with researchers. This has led to a better understanding of selected farming systems, identification of technologies that have potential for testing by farmers, and better understanding of the criteria farmers consider important for forages to be useful within those farming systems.
Monitoring Kinetics Of Readily Available Fermentable Components By Means Of In-Vitro Gas Production, G Pichard, G Jaurena, M A. Bruni
Monitoring Kinetics Of Readily Available Fermentable Components By Means Of In-Vitro Gas Production, G Pichard, G Jaurena, M A. Bruni
IGC Proceedings (1993-2023)
In vitro rumen incubations were used for measuring substrate disappearance and gas production dynamics. Samples were neutral detergent extracts of alfalfa and orchardgrass with or without added glucose. A logistic multi-pool model was used for describing feed fractions with distinct kinetic parameters, namely pools A, B1, B2 and C that represent fractions of increasing refractoriness. This technique based on gas measurement allowed to monitor early fermentation kinetics of readily available substrates thus overcoming the limitations encountered in traditional in vitro substrate disappearance. Pools A, B1 and B2 showed specific rates near 0.14 , 0.08 and 0.02 and lags of zero, …
The Energetic Utilization Of Forages In Fresh And Dried Condition By Ruminants, W Jentsch
The Energetic Utilization Of Forages In Fresh And Dried Condition By Ruminants, W Jentsch
IGC Proceedings (1993-2023)
The influence of dehydration of forages on digestibility and energy utilization was measured by indirect calorimetry in respiration chambers with adult wether sheep as a model for ruminants. Comparisons were carried out between fresh and carefully dried forages (experiment 1) and between fresh and not only carefully but also severely dried forages (experiment 2). Careful drying caused no change, but severe drying decreased energy and especially crude protein digestibility. There were no differences in utilization of metabolizable energy between fresh and carefully or severely dried forages.
Forage Productivity Evaluation And Geographic Information Systems In Temperate Semi-Arid Agro-Ecosystem, H Salinas, R Ramirez, J Zegbe, G Medina, R A. Martinez
Forage Productivity Evaluation And Geographic Information Systems In Temperate Semi-Arid Agro-Ecosystem, H Salinas, R Ramirez, J Zegbe, G Medina, R A. Martinez
IGC Proceedings (1993-2023)
700,000 ha of the temperate semi-arid area of Zacatecas state are grown with rainfed crops. Low productivity is obtained from these crops: 350 kg/ha of beans grain and 500 kg/ha of corn grain. This state is characterized by a wide range of topographic and climatic values. A need for alternative crops led to establishment of a trial to evaluate rainfed forages, and to know in what range these could be located. Geographic information systems were used to find out the potential area of the species. Results indicated that sorghum presented a higher yield (5822 kgDM/ha) than sorghum x sudan (5460), …
Use Of The Grazing Animal In Forage Breeding, J H. Bouton, C S. Hoveland, R N. Gates
Use Of The Grazing Animal In Forage Breeding, J H. Bouton, C S. Hoveland, R N. Gates
IGC Proceedings (1993-2023)
The objective of these studies was to determine, in the context of a forage breeding program, the effect of cattle grazing on survival of alfalfa (Medicago sativa L.), red clover (Trifolium pratense L.), and tall fescue (Festuca arundinacea Schreb.). Different cultivars of each species were compared in grazed and ungrazed areas. Results consistently demonstrated that grazing reduced plant stands when compared to ungrazed conditions for each species tested. In alfalfa, however, cultivars developed for grazing tolerance showed much better grazing survival. Infection with the fungal endophyte, Acremonium coenophialum Morgan-Jones & Gams, likewise substantially increased grazing survival in …
Ruminal Fill Effect Of Forages: Prediction And Relationship With Voluntary Intake, R Baumont, A Barlet, J Jamot
Ruminal Fill Effect Of Forages: Prediction And Relationship With Voluntary Intake, R Baumont, A Barlet, J Jamot
IGC Proceedings (1993-2023)
Voluntary dry matter intake (VDMI) and rumen fill were measured on sheep fed with 18 forages ranging from wheat straw to lucerne hay. In vivo fill effect (IVFE i.e. rumen DM pool divided by VDMI), in situ degradability, cell-wall composition, pepsin-cellulase digestibility and in vitro gas production were determined. In situ estimated fill effect (ISFE) was calculated as the retention time of insoluble potential degradable and undegradable fractions using a constant rate of passage. ISFE and IVFE were highly correlated (r2=0.89) but ISFE values were lower than IVFE values because in situ degradability does not integrate comminution time of …
European Cooperation On Forage Genetic Resources, P Marum, T Gass
European Cooperation On Forage Genetic Resources, P Marum, T Gass
IGC Proceedings (1993-2023)
European cooperation on forage genetic resources is coordinated within the framework of ECP/GR. Today 20 specific European forage databases are maintained by different institutions. The databases hold passport data and, to some extent, characterisation data for a total of 43993 accessions maintained in collections throughout Europe. A European Core Collection is has been established in Lolium perenne and is currently under evaluation at 19 sites.
Contribute To A Definition Of Extensive Grazing (Mediterranean), J. Potes, J. P. F. Almeida, C. Matos, A. Teixeira
Contribute To A Definition Of Extensive Grazing (Mediterranean), J. Potes, J. P. F. Almeida, C. Matos, A. Teixeira
IGC Proceedings (1993-2023)
The subject of this paper is a definition of Extensive Grazing from Extensive Systems of Animal Production in Mediterranean environments. The edaphoclimatic characterization is essential to understand the low level of primary productivity as a consequence of irregular precipitation over the year and its absence during the long, dry and hot summer. The powerless of soils justify the limited contribution of plants and make clear the necessary recovery of the soil and storage of water naturally (soil) or artificially (irrigation). Considering the IPBES (Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services) definition of extensive grazing it has been used the …
Development Of Forage Curriculum For Extension Educators In The Southeast Usa, L. S. Silva, L. Dillard, K. Mullenix, M. Wallau, J. J. Tucker, C. Vasco
Development Of Forage Curriculum For Extension Educators In The Southeast Usa, L. S. Silva, L. Dillard, K. Mullenix, M. Wallau, J. J. Tucker, C. Vasco
IGC Proceedings (1993-2023)
In the Southeast USA, livestock production is one of the largest agricultural activities, and forages are the primary feed source. Most livestock systems are highly dependent on off-farm inputs to support forage production and animal performance, which elevates production costs and the activity's carbon footprint. There is a strong need to develop forage educational resources to enhance productivity, environmental sustainability, resilience, and profitability of agricultural systems in the region. This multi-disciplinary initiative was a collaboration among several land-grant Universities across the region. The objective was to develop decision tools and provide in-classroom training associated with hands-on demonstrations to Extension agents …
Barriers/Drivers Of Diverse Perennial Systems: Policy Recommendations, M. L. Krome, A. S. Finan, J. Obudzinski, N. Serrano
Barriers/Drivers Of Diverse Perennial Systems: Policy Recommendations, M. L. Krome, A. S. Finan, J. Obudzinski, N. Serrano
IGC Proceedings (1993-2023)
Despite growing documentation of perennial- and grass-based systems’ importance in addressing many ecological, infrastructural, farmer profitability, and climate concerns, these systems do not predominate on most United States farm and ranch lands. To better understand what impedes their wider adoption, we undertook four focus groups of diverse current and potential farmers using perennial systems. We were especially interested in how these farmers access, or don’t, insurance, credit, and federal programs, identifying patterns among farmers embracing more sustainable practices. Our virtual focus groups comprised 16 farmers in ten states, transecting climate zones and representing both rural and urban production systems and …
Tall Fescue And Orchardgrass Productivity And Persistence Under Grazing Systems In Tennessee, K. Johnson, R. N. Oakes, G. Bates
Tall Fescue And Orchardgrass Productivity And Persistence Under Grazing Systems In Tennessee, K. Johnson, R. N. Oakes, G. Bates
IGC Proceedings (1993-2023)
The primary forage species used by cow-calf producers in grazing systems in Tennessee is tall-fescue. Tall fescue is considered an excellent cool-season perennial forage crop due to its high quality, production, and extended growing season. However, most of these tall fescue grazing systems are composed of tall fescue cv. Kentucky 31, which is known for containing a fungus endophyte that can be toxic to animals. Alternatively, orchardgrass is also a vastly used and important perennial cool-season forage in the United States. It can be used as a pasture, hay, and is a high-quality forage that is desirable for most livestock …
Genotype-By-Environment Interaction In Interspecific Urochloa Hybrids Using Factor Analytic Models, R. N. Jauregui, L. M. Hernandez, J. S. Aparicio, L. J. Mazabel, J. A. Cardoso Arango, L. M. Atencio-Solano, S. L. Mejía Kerguelén, V. Castiblanco, M. Peters
Genotype-By-Environment Interaction In Interspecific Urochloa Hybrids Using Factor Analytic Models, R. N. Jauregui, L. M. Hernandez, J. S. Aparicio, L. J. Mazabel, J. A. Cardoso Arango, L. M. Atencio-Solano, S. L. Mejía Kerguelén, V. Castiblanco, M. Peters
IGC Proceedings (1993-2023)
Environmental factors can influence plant phenotypes shaping the expression of pastures. The ability to test genotypes in multiple environments is critical in a breeding program because important traits are heavily influenced by the environment. Nutritional quality is critical in forage breeding because it affects the rate of live weight gain in livestock as well as the quality of end products such as milk and meat. However, there is not much information on the environmental effect on agronomic and nutritional quality traits in tropical forages. For this reason, the objective of the present study was to investigate the genotype-by-environment interaction in …