University of Nebraska at Lincoln
Utah State University
Department of Primary Industries and Regional Development, Western Australia
Michigan Technological University
Langston University
Patterns And Sources Of Variation In Heterospecific Pollen Deposition In Flowers Of The Native Blue Cardinal Flower (Lobelia Siphilitica),
2023
East Tennessee State University
Patterns And Sources Of Variation In Heterospecific Pollen Deposition In Flowers Of The Native Blue Cardinal Flower (Lobelia Siphilitica), Allie Drinnon
Undergraduate Honors Theses
Plants species interactions via pollinators are a model system to understand the mechanisms that generate plant diversity in nature. However, most studies have focused on plant-plant interactions via pollinator attraction while ignoring the role of plant-plant interactions via pollen transfer. Heterospecific pollen transfer (henceforth HP) can be common and have negative fitness effects. Negative HP fitness effects may prompt the evolution of adaptive strategies to minimize them. However, the extent of spatial variation in HP load size within and among populations, a tenet for natural selection, remains unexplored. Such knowledge would hence constitute a first step in advancing our understanding …
Ruminal Proteolysis In Forages With Distinct Endopeptidases Activities,
2023
Pontificia Universidad Católica de Chile
Ruminal Proteolysis In Forages With Distinct Endopeptidases Activities, G. Pichard, C. Tapia, R. Larrain
International Grassland Congress Proceedings
Improving livestock efficiency in utilisation of nitrogen resources continues to be a major environmental and economic objective. Zhu et al. (1999) have shown that plant endopeptidases are activated as a response to cutting stress. Previous work in our laboratory explored over 300 entries of forage genotypes and found a broad diversity in enzymatic activity by means of hydrolysis in gelatine and direct autolysis assays in forage tissues. The objective of this work was to assess if the species previously identified as having high or low endopeptidase activity, would behave consistently when exposed to ruminal microbial proteolysis.
Effects Of Particle Size In Forage Samples For Protein Breakdown Studies,
2023
Pontificia Universidad Católica de Chile
Effects Of Particle Size In Forage Samples For Protein Breakdown Studies, G. Pichard, C. Tapia
International Grassland Congress Proceedings
Coupling ruminal processes of hydrolysis and synthesis continues to be a research issue where more progress is needed. This requires the development of good protein assessment methods, particularly when representing the breakdown processes that occur in fresh pastures eaten by herbivores. Laboratory analyses need to deal with small and homogeneous samples, but the mechanical reduction of particle size may not reflect the actual digestion kinetics occurring when the original fresh forage is consumed. Such physical traits may alter the release of non-structural compounds and the penetration of microbial enzymes (Boudon et al., 2002). The objective of this work was …
Prediction Of Indigestible Ndf Content Of Grass And Legume Silages By Nirs,
2023
Valio Ltd., Finland
Prediction Of Indigestible Ndf Content Of Grass And Legume Silages By Nirs, L. Nyholm, M. Rinne, M. Hellämäki, P. Huhtanen, J. Nousiainen
International Grassland Congress Proceedings
The future feed evaluation systems based on mechanistic digestion models require reliable estimates of forage digestible and indigestible NDF content (DNDF and INDF). The objective of this study was to examine the potential of near infrared reflectance spectroscopy (NIRS) in predicting INDF content of grass and legume silages.
A New System For The Evaluation Of The Fermentation Quality Of Silages,
2023
Humboldt-University of Berlin, Germany
A New System For The Evaluation Of The Fermentation Quality Of Silages, K. Weiß, E. Kaiser
International Grassland Congress Proceedings
Depending on the content of nitrate in green forage, the pattern of fermentation products in silages differ significantly (Weiß & Kaiser, 2001). The systems, which are now common in practice for evaluating the quality of silage fermentation, characterise fermentation quality incorrectly because the evaluation is influenced by the chemical composition of green forage. The aim of this work was to derive an evaluation system for fermentation quality, which is independent from the chemical composition of green forage.
Analysis Of Silage Fermentation Characteristics Using Transflectance Measurements By Near Infrared Spectroscopy,
2023
Servicio Regional de Investigación y Desarrollo Agroalimentario, Spain
Analysis Of Silage Fermentation Characteristics Using Transflectance Measurements By Near Infrared Spectroscopy, A. Martínez, A. Soldado, R. Garcia, D. Sánchez, B. De La Roza-Delgado
International Grassland Congress Proceedings
The fermentation end products as lactic acid, volatile fatty acids and ammonia-nitrogen, are important indicators of the efficiency of silage fermentation and are closely related to nutritive value of them (Jaster, 1995). Drying is problematic in the case of silage as many fermentation products are volatile and may get lost during the drying process. This may be a reason why NIR technology is being little used for the evaluation of silage fermentation characteristics. The feasibility of using near infrared transflectance spectroscopy to evaluate the content in fermentation end products of grass and maize fresh silage was investigated in this study.
Development Of A Method For The Fast And Complete Assessment Of Quality Characteristics In Undried Grass Silages By Means Of An Nir-Diode Array Spectrometer,
2023
Federal Agricultural Research Centre, Germany
Development Of A Method For The Fast And Complete Assessment Of Quality Characteristics In Undried Grass Silages By Means Of An Nir-Diode Array Spectrometer, H. Gibaud, C. Paul, J. M. Greef, B. Ruser
International Grassland Congress Proceedings
Traditionally, the determination of grass silage is very time consuming and needs a lot of manpower and chemicals. The advantages of conventional laboratory NIRS instruments are well known but their disadvantage lies in their lacking suitability for on-farm use. A new type of spectrometer based on diode arrays may be used for this purpose. However, these new instruments still need to be calibrated for an accurate estimate of the fermentative and nutritive value of wet and unchopped grass silage.
A Simple Method For The Correction Of Fermentation Losses Measured In Laboratory Silos,
2023
Elmenhorst, Germany
A Simple Method For The Correction Of Fermentation Losses Measured In Laboratory Silos, F. Weissbach
International Grassland Congress Proceedings
Dry matter (DM) losses caused by formation of gaseous fermentation products can be measured by different methods. The most common method (A) is measuring the difference between the DM input and output of a silo. Other methods are based on the measurement of the fermentation gases which spontaneously leave the silo, either directly by collecting them (B) in a special absorbent like KOH or, much more easily, by weighing the filled silo at the beginning and the end of the fermentation process (C). The figures obtained by B and C are substantially smaller than those by A. This difference represents …
Prediction Of Red Clover Content In Mixed Swards By Near-Infrared Reflectance Spectroscopy,
2023
Catholic University of Louvain, Belgium
Prediction Of Red Clover Content In Mixed Swards By Near-Infrared Reflectance Spectroscopy, B. Deprez, D. Stilmant, C. Clément, C. Decamps, A. Peeters
International Grassland Congress Proceedings
Because of the legume fixation capacity, their high protein content, digestibility and intake characteristics, more and more attention is paid to grassland clover content. In field experiments, clover content must often be determined, for example to quantify nitrogen flux or the best practices to manage such species (Stilmant et al., 2004). However hand sorting of clover and grass, even if accurate, is time-consuming and has a high labour cost. In comparison, accuracy of visual estimation of clover content, directly in the field, varies according to training and experience. Near-infrared reflectance spectroscopy (NIRS) has been proposed as a method for …
Intake And Milk Production Of Lactating Dairy Cows Grazing Diverse Forage Mixtures Over Two Grazing Seasons,
2023
U.S. Department of Agriculture
Intake And Milk Production Of Lactating Dairy Cows Grazing Diverse Forage Mixtures Over Two Grazing Seasons, K. Soder, M. A. Sanderson, J. L. Stack, L. Muller
International Grassland Congress Proceedings
Voluntary intake and stocking rate are key determinants of animal performance on pasture. Greater plant diversity in grassland plant communities has been linked to increased primary production, greater stability in response to disturbance, and reduced weed pressure. Thus, increasing plant diversity may be one approach to improving animal productivity. An experiment was conducted to determine the effects of forage diversity on intake and milk production of lactating dairy cows over two grazing seasons.
A Comparison Of Perennial Ryegrass Cultivars Differing In Heading Date And Grass Ploidy For Grazing Dairy Cows At Two Different Stocking Rates,
2023
Teagasc, Ireland
A Comparison Of Perennial Ryegrass Cultivars Differing In Heading Date And Grass Ploidy For Grazing Dairy Cows At Two Different Stocking Rates, M. O'Donovan, G. Hurley, L. Delaby, G. Stakelum
International Grassland Congress Proceedings
Animal productivity is the ultimate performance indicator of any new grass cultivar. Direct assessment is complex and expensive. Recent research has identified a number of important sward factors that influence intake and production. The most important factor appears to be green leaf mass. The objective of this two year study was to investigate the effects on milk yield, composition and grass intake of grass cultivars with contrasting heading dates (HD) and grass ploidies (PL) when grazed at different stocking rates.
In Situ Rumen Degradability Of Perennial Ryegrass Cultivars Differing In Ploidy And Heading Date In Ireland,
2023
Teagasc, Ireland
In Situ Rumen Degradability Of Perennial Ryegrass Cultivars Differing In Ploidy And Heading Date In Ireland, V. Olsson, J. J. Murphy, F. P. O'Mara, M. O'Donovan, F. J. Mulligan
International Grassland Congress Proceedings
Grazed grass is the predominant feed in Irish dairy and beef cattle production systems. Knowledge of the degradability characteristics of protein in Irish forages is necessary for the establishment of protein values (PDIE and PDIN values) for these. This knowledge would also facilitate more accurate formulation of supplements for grass diets with the potential to reduce nitrogen (N) excretion.
Grazing Behaviour Of Beef Steers Grazing Kentucky 31 Endophyte Infected Tall Fescue, Q4508-Ar542 Novel Endophyte Tall Fescue, And Lakota Prairie Grass,
2023
Virginia Polytechnic Institute and State University
Grazing Behaviour Of Beef Steers Grazing Kentucky 31 Endophyte Infected Tall Fescue, Q4508-Ar542 Novel Endophyte Tall Fescue, And Lakota Prairie Grass, H. T. Boland, G. Scaglia, J. P. Fontenot, A. O. Abaye, R. Smith
International Grassland Congress Proceedings
Tall fescue is the most dominant grass used for pasture in the U.S. covering over 14 million ha. As a result, fescue toxicosis is a major concern among producers, especially during the summer months when the symptoms, such as reduced weight gains, are most pronounced. Producers need alternative forages for grazing cattle that do not have the negative effects associated with endophyte infected tall fescue. The objective of this experiment was to determine the grazing behaviour of cattle on Kentucky 31 endophyte infected (E+) tall fescue (Festuca arundinacea Schreb.), Q4508-AR542 (Q) novel endophyte tall fescue, and Lakota (L) …
Caucasian Clover Is More Productive Than White Clover In Temperate Pastures,
2023
Teagasc, Ireland
Caucasian Clover Is More Productive Than White Clover In Temperate Pastures, A. D. Black, D. J. Moot, R. J. Lucas
International Grassland Congress Proceedings
White clover (wc) (Trifolium repens) is present and is often the dominant legume in the >11 m ha of grassland in New Zealand (NZ). However, wc has limitations and normally contributes less than 20% of total annual pasture dry matter (DM) production. The use of a wider range of legume species is one way to increase legume percentage in wc/grass pastures. Caucasian (Cc) or Kura clover (Trifolium ambiguum) is a persistent legume which is slower to establish than wc but can increase total legume production (Cc plus volunteer wc) and hence N2 fixation and animal productivity. …
Response Of Warm-Season Grass Pasture To Grazing Period And Recovery Period Lengths,
2023
University of Nebraska-Lincoln
Response Of Warm-Season Grass Pasture To Grazing Period And Recovery Period Lengths, B. E. Anderson, W. H. Schacht
International Grassland Congress Proceedings
Grazing period and recovery period lengths are key variables influencing grassland production and composition. Systems with short grazing periods and lengthy recovery periods require numerous pastures. Relatively high facility and management costs associated with multiple-pasture systems can be justified only if plant response is favorable and/or if livestock production is improved. This study determined the effects of 4 different combinations of grazing period/recovery period lengths on percentage basal cover (PBC) and relative species composition (RSC) of seeded, warm-season grass pasture.
Yield Components In A Signal Grass-Clitoria Mixture Grazed At Different Herbage Allowance,
2023
Campo Experimental Chilpancingo, Mexico
Yield Components In A Signal Grass-Clitoria Mixture Grazed At Different Herbage Allowance, R. Jiménez-Guillen, S. Rojas-Hernández, J. Olivares-Pérez, A. Martínez-Hernández, J. Pérez-Pérez
International Grassland Congress Proceedings
A Signal grass-Clitoria mixture provides good quality forage in the dry tropic of southern Mexico. However, its response in leaf and stem yields to grazing at different daily herbage allowances is not well documented. The objective of this study was to determine available and residual leaf and stem yields in a Signal grass (Brachiaria decumbens)-Clitoria (Clitoria ternatea) mixture grazed at different daily herbage allowance.
Renovation-Year Forage Quality Of Grass Pastures Sod-Drilled With Kura Clover,
2023
University of Minnesota
Renovation-Year Forage Quality Of Grass Pastures Sod-Drilled With Kura Clover, P. R. Peterson, P. Seguin, G. Laberge, C. C. Sheaffer
International Grassland Congress Proceedings
Including legumes can enhance yield, quality, and animal performance potential of grass pastures. Kura clover is an exceptionally winter hardy forage legume with high forage quality (Taylor & Smith, 1998). However, its seedling vigor is poor. Herbicide sod suppression prior to sod drilling enabled kura clover to establish in the north central USA and eastern Canada (Cuomo et al., 2001; Laberge et al., 2005), but its percentage of renovation-year forage yield was less than for sod-seeded red or white clover. The objective of this study was to determine the influence of herbicide suppression and clover species on renovation-year …
Farm Performance From Holstein-Friesian Cows Of Three Genetic Strains On Grazed Pasture,
2023
Dexcel, New Zealand
Farm Performance From Holstein-Friesian Cows Of Three Genetic Strains On Grazed Pasture, K. A. Macdonald, B. S. Thorrold, C. B. Glassey, J. A. S. Lancaster, G. A. Verkerk, J. E. Pryce, C. W. Holmes
International Grassland Congress Proceedings
Dairy selection objectives and farm production systems in USA and Europe are different from those in New Zealand (NZ). The use of overseas semen in NZ in the last 20 years has changed the genetics of the former NZ Holstein-Friesian (HF) strain. This trial was designed to demonstrate the genetic progress in the NZ HF dairy herd in the last 25 years and how high production potential North American HF cows perform under pasture-based feeding systems.
Forage Yield And Quality Of Signal Grass-Clitoria Mixture Grazed At Different Frequencies,
2023
Campo Experimental Chilpancingo, Mexico
Forage Yield And Quality Of Signal Grass-Clitoria Mixture Grazed At Different Frequencies, R. Jiménez-Guillen, J. Olivares-Pérez, S. Rojas-Hernández, A. Martínez-Hernández
International Grassland Congress Proceedings
A Signal grass-Clitoria mixture provides good quality forage in the dry tropic of southern Mexico. Grazing frequency is a management tool that determines yield, botanical components and quality of pastures. The objective of this study was to determine forage yield, quality and botanical components in a Signal grass (Brachiaria decumbens)-Clitoria (Clitoria ternatea) mixture when grazed at different frequencies.
Genetic Alternatives For Dairy Producers Who Practise Grazing,
2023
U.S. Department of Agriculture
Genetic Alternatives For Dairy Producers Who Practise Grazing, H. D. Norman, J. R. Wright, R. L. Powell
International Grassland Congress Proceedings
The decline in cow fertility has had a negative impact on all dairy producers, especially those that practise seasonal calving with pasture-based dairying. One alternative that is being tried in the United States (US) by a few graziers is to use bulls from New Zealand (NZ) because NZ producers have practised seasonal calving for some time. However, genotype-environment interaction is a concern; genetic correlations that were derived by the International Bull Evaluation Service (2004) between bull rankings from different countries were often lower for NZ than for other countries. The objective of this study was to compare the performance of …
