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A Typological And Chemical Analysis Of Roman Oil Lamps From Poggio Del Molino, Brandon Tejo Jun 2023

A Typological And Chemical Analysis Of Roman Oil Lamps From Poggio Del Molino, Brandon Tejo

Dissertations, Theses, and Capstone Projects

Terracotta lamps, known to the Romans as lucernae, are small, handheld, often decorated objects which provided ancient people light. To modern researchers, they serve as tools for dating stratigraphy and iconographic studies. Beyond their immediately apparent aesthetic and symbolic value, the chemical compositions of the clay of these lamps reflect their origin. This study complements archaeological typologies with chemometric analyses to describe 16 Late Republican and Imperial Roman lamps recovered from the villa at Poggio del Molino (PdM), Tuscany. These finds were recovered from the 2021 and 2022 PdM excavations. The combined approach of typology with X-ray Diffraction (XRD) …

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Characterization Of Boreal-Arctic Vegetation Growth Phases And Active Soil Layer Dynamics In The High-Latitudes Of North America: A Study Combining Multi-Year In Situ And Satellite-Based Observations, Michael G. Brown Jun 2023

Characterization Of Boreal-Arctic Vegetation Growth Phases And Active Soil Layer Dynamics In The High-Latitudes Of North America: A Study Combining Multi-Year In Situ And Satellite-Based Observations, Michael G. Brown

Dissertations, Theses, and Capstone Projects

This dissertation examined the seasonal freeze/thaw activity in boreal-Arctic soils and vegetation physiology in Alaska, USA and Alberta, Canada, using in situ environmental measurements and passive microwave satellite observations. The boreal-Arctic high-latitudes have been experiencing ecosystem changes more rapidly in comparison to the rest of Earth due to the presently warming climatic conditions having a magnified effect over Polar Regions. Currently, the boreal-Arctic is a carbon sink; however, recent studies indicate a shift over the next century to become a carbon source. High-latitude vegetation and cold soil dynamics are influenced by climatic shifts and are largely responsible for the regions …

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Effect Of Condensed Tannins In Sainfoin On In Vitro Protein Solubility Of Lucerne, J. Aufrère, M. Dudilieu, C. Poncet, R. Baumont May 2023

Effect Of Condensed Tannins In Sainfoin On In Vitro Protein Solubility Of Lucerne, J. Aufrère, M. Dudilieu, C. Poncet, R. Baumont

IGC Proceedings (1977-2023)

Proteins of fresh legume forages such as lucerne are highly degraded in the rumen, resulting in their inefficient use by the animal. The condensed tannins (CT) present in some forages can improve the nutritional value of these forages and of associated feeds in the diet. Previous in vitro work (Waghorn & Shelton, 1997) showed that CT from Lotus corniculatus are able to bind with and precipitate protein from a ryegrass/clover pasture, but when these forages were fed to sheep, the CT effects on digestion and animal performance were weak. This revealed a need for a better understanding of the mechanism …

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Herbage Production, Nitrogen Fixation And Condensed Tannin Concentrations In Lotus Glaber Mill. Germplasm, H. Acuña, M. Figueroa, P. Hellman, A. Concha May 2023

Herbage Production, Nitrogen Fixation And Condensed Tannin Concentrations In Lotus Glaber Mill. Germplasm, H. Acuña, M. Figueroa, P. Hellman, A. Concha

IGC Proceedings (1977-2023)

Lotus glaber (Lg) grows on clay, sandy and medium textured soils in central Chile (32º to 38º S). The diversity of environments where the species grows naturally supports the hypothesis that genetic variability would be found. The objectives of the experiment were to characterise accessions of Lg collected in the region for dry matter (DM) production, comparative capacity to fix atmospheric N and condensed tannins (CT) in Lg grown on clay soils used for cropping rice.

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Condensed Tannins In Different Varieties Of Lotus Corniculatus, Christina L. Marley, Rhun Fychan, R. Jones May 2023

Condensed Tannins In Different Varieties Of Lotus Corniculatus, Christina L. Marley, Rhun Fychan, R. Jones

IGC Proceedings (1977-2023)

Research has shown that Lotus corniculatus may provide benefits as a grazing forage for ruminants, because of improved efficiency of protein utilisation in part due to the presence of condensed tannins (CT) in the forage. Lotus species have been found to contain different CT (Aerts et al., 1999). The aim of this experiment was to determine if differences exist in CT concentration among L. corniculatus varieties.

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Ariation In Tannin Content And Morphological Traits In Lotus Corniculatus L. (Bird’S-Foot Trefoil), A. H. Marshall, F. Ribaimont, R. P. Collins, D. Bryant, M. T. Abberton May 2023

Ariation In Tannin Content And Morphological Traits In Lotus Corniculatus L. (Bird’S-Foot Trefoil), A. H. Marshall, F. Ribaimont, R. P. Collins, D. Bryant, M. T. Abberton

IGC Proceedings (1977-2023)

Lotus corniculatus L. (bird's-foot trefoil) is a potentially valuable species for UK grassland agriculture. The herbage contains proanthocyanidins, or condensed tannins (CT's), which help to reduce bloat, have anthelmintic properties, can protect protein in the rumen, and thus potentially reduce N losses to the environment. It is currently a relatively minor species within UK grassland, as available varieties lack persistence in mixed swards (Hopkins et al., 1996). The seed used is of foreign bred varieties with no varieties bred specifically for the UK environment. To explore the feasibility of breeding L. corniculatus for the UK, variation in morphological traits, …

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Light Intensity Is Positively Correlated With The Synthesis Of Condensed Tannins In Lotus Corniculatus, Sergio Arcioni, T. Bovone, F. Damiani, F. Paolocci May 2023

Light Intensity Is Positively Correlated With The Synthesis Of Condensed Tannins In Lotus Corniculatus, Sergio Arcioni, T. Bovone, F. Damiani, F. Paolocci

IGC Proceedings (1977-2023)

The importance of Condensed Tannins (CT) in forage legumes has been well documented in several studies. The role of plant genetics in this field is the acquisition of competences in order to be able to modulate CT synthesis in leaves of these species. The role of light has been investigated in this work on the increase of condensed tannin levels in leaves of two contrasting genotypes of birdsfoot trefoil (Lotus corniculatus).

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Condensed Tannin Concentration And Herbage Accumulation Of A White Clover Bred For Increased Floral Condensed Tannin, V. T. Burggraaf, S. L. Woodward, D. R. Woodfield, E. R. Thom, G. C. Waghorn, P. D. Kemp May 2023

Condensed Tannin Concentration And Herbage Accumulation Of A White Clover Bred For Increased Floral Condensed Tannin, V. T. Burggraaf, S. L. Woodward, D. R. Woodfield, E. R. Thom, G. C. Waghorn, P. D. Kemp

IGC Proceedings (1977-2023)

White clover is a high quality feed for ruminants, however, its high protein content results in excessive urea excretion in urine and can cause bloat, reducing its potential value for animal production. The condensed tannins (CT) in some forages can reduce these problems, but plants may have poor agronomic performance. White clover produces CT in its flower heads, but herbage CT concentrations are normally too low to benefit animals. This paper reports CT concentrations and herbage accumulation over 2 years of an experimental line of white clover (HT) selected for increased flowering and floral CT concentrations.

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Effects Of Simulated High-Sugar Forages On Grazing Behaviour Of Sheep, Gerald P. Cosgrove, A. J. Parsons May 2023

Effects Of Simulated High-Sugar Forages On Grazing Behaviour Of Sheep, Gerald P. Cosgrove, A. J. Parsons

IGC Proceedings (1977-2023)

Sustaining an optimum composition in mixed-species pasture and in the diet of grazing animals is constrained by many factors. Altering the concentration of water soluble carbohydrate (WSC) of one species to improve its nutritional value for animals may not deliver the benefits in the assumed manner if it also affects preference and the balance of species in the pasture. Furthermore, associated changes in other constituents (e.g. fibre, protein) make it difficult to attribute animal responses solely to the manipulated trait (e.g. Lee et al. 2000). The objective of this study was to simulate changes in the concentration of water soluble …

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High Floral Tannin White Clover Reduces Rumen Ammonia Concentrations In Dairy Cows, V. T. Burggraaf, G. C. Waghorn, S. L. Woodward, D. R. Woodfield, E. R. Thom, P. D. Kemp May 2023

High Floral Tannin White Clover Reduces Rumen Ammonia Concentrations In Dairy Cows, V. T. Burggraaf, G. C. Waghorn, S. L. Woodward, D. R. Woodfield, E. R. Thom, P. D. Kemp

IGC Proceedings (1977-2023)

White clover produces high quality forage for ruminant production, but it results in high rumen ammonia concentrations, indicating extensive protein degradation. The excess ammonia is absorbed through the rumen and excreted as urea in urine, at a cost to the animal and the environment. Condensed tannins (CT) contained in some forages reduce proteolysis in the rumen, which can lead to increased amino acid absorption and therefore improved animal performance. White clover produces CT in its flower heads, but concentrations are normally too low to benefit animals. This paper reports on comparisons of rumen ammonia concentrations in dairy cows grazing HT …

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Substrate-Dependent Activation Of Polyphenol Oxidase In Red Clover, Ana L. Winters, F. R. Minchin, P. Morris May 2023

Substrate-Dependent Activation Of Polyphenol Oxidase In Red Clover, Ana L. Winters, F. R. Minchin, P. Morris

IGC Proceedings (1977-2023)

Polyphenol oxidases (PPO) are copper metaloproteins that catalyse the oxidation of o-diphenols to quinones, highly reactive molecules which readily bind to nucleophilic sites on cellular components and proteins. Red clover protein, due to this enzyme is resistant to protease degradation during. Theses enzymes (circa. 60-65 kDa) are located in the thylakoid lumen and can be converted to a 40-45 kDa form by proteolysis both in vitro and in vivo (Gelder et al., 1997). Conversion to the smaller form has been demonstrated to confer activity at neutral pH. Other treatments, such as the presence of lipids or detergents …

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Variation In Protein Quality Of Forage Legumes During Spring Growth, M. Gierus, J. Kleen, F. Taube May 2023

Variation In Protein Quality Of Forage Legumes During Spring Growth, M. Gierus, J. Kleen, F. Taube

IGC Proceedings (1977-2023)

The utilisation of forage legumes in combination with reduced N inputs as fertilisers is an alternative for the production of high quality forage. Although white clover (WC) is widely used in grassland and has a high content of crude protein (CP), a combination of this high CP content with a high proportion of rapidly-available proteins and fast degradation rate in the rumen may reduce the efficiency of N use by ruminants in comparison with other forage legumes. The objective of the present study was to investigate the variation in content of CP fractions A, B and C in different forage …

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Effects Of Particle Size In Forage Samples For Protein Breakdown Studies, G. Pichard, C. Tapia May 2023

Effects Of Particle Size In Forage Samples For Protein Breakdown Studies, G. Pichard, C. Tapia

IGC Proceedings (1977-2023)

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 …

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Ruminal Disappearance And Passage Rates In Fresh Nezasa Dwarf Bamboo Growing In Japanese Native Pasture, Masato Yayota, J. Karashima, T. Kokestu, M. Nakano, Shigeru Ohtani May 2023

Ruminal Disappearance And Passage Rates In Fresh Nezasa Dwarf Bamboo Growing In Japanese Native Pasture, Masato Yayota, J. Karashima, T. Kokestu, M. Nakano, Shigeru Ohtani

IGC Proceedings (1977-2023)

Nezasa dwarf bamboo (Pleioblastus chino makino) is one of major native forages for grazing in Japan. However its nutritional utilisation in the rumen has been little studied. The object of this research was to measure ruminal disappearance and passage rates in fresh Nezasa dwarf bamboo compared with improved grass.

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Ruminal Dry Matter, Neutral Detergent Fibre And Acid Detergent Fiber Degradation Kinetics Of Dominant Pasture Forages In Kurdestan Province Of Iran, A. A. Sadeghi, P. Shawrang, A. Nikkhah May 2023

Ruminal Dry Matter, Neutral Detergent Fibre And Acid Detergent Fiber Degradation Kinetics Of Dominant Pasture Forages In Kurdestan Province Of Iran, A. A. Sadeghi, P. Shawrang, A. Nikkhah

IGC Proceedings (1977-2023)

Neutral detergent fiber (NDF) is a major chemical component of forages and its degradability (dNDF) is an essential parameter in predicting their energetic value. Moreover, dNDF has been used in models to estimate the physical fill of fibrous feeds in the rumen and, therefore, the intake capacity of animals. As the available information on the nutritive value of pastoral forages is limited a study was undertaken to measure chemical composition and cell wall degradation kinetics of eight pasture forages in the rumen.

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The Effects Of Urease Source And Moisture Content On The Nutritive Value Of Brachiaria BrizantHa Hay Treated With Urea, Ricardo A. Reis, L. M. A. Bertipaglia, G. M. P. Melo, A. P. Oliveira, S. Luca May 2023

The Effects Of Urease Source And Moisture Content On The Nutritive Value Of Brachiaria BrizantHa Hay Treated With Urea, Ricardo A. Reis, L. M. A. Bertipaglia, G. M. P. Melo, A. P. Oliveira, S. Luca

IGC Proceedings (1977-2023)

Ammoniation has a high potential to increase the nutritive value (NV) of mature tropical grasses hays. Urea utilisation, like ammonia, seems to be a promising alternative for on-farm treatment of low quality forage in Brazil. Urea has the advantages over anhydrous ammonia of being widely available, easier to handle and, in some countries, less expensive. The aim of this work was to study the effects on the efficiency of urea treatment of palisade grass (Brachiaria brizantha cv. Marandu) hay of the moisture level, and the urease source.

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Herbage Mass And In Situ Dry Matter Ruminal Degradation Kinetics Of Brachiaria Spp, E. Valencia-Chin, A. A. Rodríguez-Carías, R. Ramos-Santana, S. Pagán-Riestra May 2023

Herbage Mass And In Situ Dry Matter Ruminal Degradation Kinetics Of Brachiaria Spp, E. Valencia-Chin, A. A. Rodríguez-Carías, R. Ramos-Santana, S. Pagán-Riestra

IGC Proceedings (1977-2023)

In Puerto Rico, Brachiaria decumbens cv. Basilisk has been promoted as a potential forage for acid soils and humid areas, but with limited success. Recently, B. brizantha cv. Marandú and a hybrid (B. brizantha x B. Ruziziensis) cv. Mulato were introduced for evaluation on acid soils and as a potential replacement for cv. Basilisk, but little information is available on yield performance under grazing or nutritive value. The objective of this study was to assess herbage mass and nutritive value of grazed pastures consisting of Basilisk, Marandú, and Mulato and determine the rate of in situ dry matter …

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Physical Impediment Towards Digestive Breakdown In Leaf Blades Of Brachiaria Brizantha, B. Lempp, Cacilda B. Do Valle, M. Das G. Morais, R. A. Borges, E. Detmann May 2023

Physical Impediment Towards Digestive Breakdown In Leaf Blades Of Brachiaria Brizantha, B. Lempp, Cacilda B. Do Valle, M. Das G. Morais, R. A. Borges, E. Detmann

IGC Proceedings (1977-2023)

Consumption of grasses is influenced by the physical properties of forages which confer resistance to digestive breakdown. Such barriers may be the proportion of indigestible tissues, girder structure and epidermal cell arrangements. Anatomical factors, if identified early are invaluable tools in breeding and selection programmes for forages of high quality. The objective of this study was to verify which anatomical attributes might be interfering in the physical resistance to rumen breakdown in Brachiaria brizantha ecotypes.

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Effects Of Forage Species And Stage Of Maturity On In Situ Disappearance Of Organic Matter And Fibre Fractions, H. S. Hussein May 2023

Effects Of Forage Species And Stage Of Maturity On In Situ Disappearance Of Organic Matter And Fibre Fractions, H. S. Hussein

IGC Proceedings (1977-2023)

Nutrient utilisation by ruminants is altered by the forage species and its maturity. Maturity is the major factor affecting forage morphology and quality. Forage quality is reduced with maturity due to a decrease in the leaf:stem ratio and an increase in fibre components (Ugherughe, 1986). Improving forage utilisation by ruminants depends on accurate measurements of their nutritive value by using in vitro and in situ methods. The objective of this study was to assess the nutritive value (i.e., extent of in situ disappearance of organic matter [OM], neutral detergent fibre [NDF], and acid detergent fibre [ADF]) of four grass species …

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The Effect Of Nitrogen Fertiliser And Season On The In Situ Degradability Of Irish Perennial Ryegrass In Cattle, V. Olsson, J. J. Murphy, F. P. O'Mara, K. O'Connell, J. Humphreys, F. J. Mulligan May 2023

The Effect Of Nitrogen Fertiliser And Season On The In Situ Degradability Of Irish Perennial Ryegrass In Cattle, V. Olsson, J. J. Murphy, F. P. O'Mara, K. O'Connell, J. Humphreys, F. J. Mulligan

IGC Proceedings (1977-2023)

In light of increasing environmental and economic pressure on agriculture to utilise resources more efficiently, protein feeding and its effects are fundamentally important. As grazed grass is the predominant feed in Irish dairy and beef cattle production systems, it is necessary to establish protein values for different grass varieties and cultivars fed. It is also important to investigate the extent of ruminal nitrogen (N) degradability for these grasses since this characteristic greatly influences environmentally damaging urinary N excretion.

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The Effect Of Cow-Diet On The Fermentation Of Forages, J. L. Burke, G. C. Waghorn, S. L. Woodward, I. M. Brookes May 2023

The Effect Of Cow-Diet On The Fermentation Of Forages, J. L. Burke, G. C. Waghorn, S. L. Woodward, I. M. Brookes

IGC Proceedings (1977-2023)

In vitro fermentation of fresh forages minced to resemble chewed material have enabled net proteolysis and volatile fatty acid (VFA) production to be measured using rumen inocula from a cow fed lucerne hay (Burke et al., 2000). However both cow and diet affect the rumen cellulolytic bacterial populations (Weimer et al., 1999) and are able to influence in vitro digestion kinetics (Mertens et al., 1998). The objective of this study was to measure cow-diet effects on in vitro digestion and fermentation of perennial ryegrass (P; Lolium perenne), sulla (S; Hedysarum coronarium), maize (M; Zea maize …

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Fibre Degradation Rate Of Perennial Ryegrass Varieties Measured Using Three Techniques: In Situ Nylon Bag, In Vivo Rumen Evacuation And In Vitro Gas Production, H. Z. Taweel, B. M. Tas, B. A. Williams, A. Elgersma, J. Dijkstra, S. Tamminga May 2023

Fibre Degradation Rate Of Perennial Ryegrass Varieties Measured Using Three Techniques: In Situ Nylon Bag, In Vivo Rumen Evacuation And In Vitro Gas Production, H. Z. Taweel, B. M. Tas, B. A. Williams, A. Elgersma, J. Dijkstra, S. Tamminga

IGC Proceedings (1977-2023)

In Western Europe, perennial ryegrass is the most widely used grass species for grazing cattle, because of its high productivity, palatability and nutritive value. However, the low dry matter intake (DMI) of perennial ryegrass pasture has been identified as a major factor limiting milk production of high producing dairy cows. Altering the chemical, physical and mechanical characteristics that contribute to its low DMI through grass breeding and the choice of variety may be a way forward in trying to maximise its DMI. This study aimed to examine whether perennial ryegrass varieties differ in their NDF degradation rates (kdNDF).

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Perennial Ryegrass Variety Differences In Nutritive Value Characteristics, T. J. Gilliland, R. E. Agnew, A. M. Fearon, F. E. A. Wilson May 2023

Perennial Ryegrass Variety Differences In Nutritive Value Characteristics, T. J. Gilliland, R. E. Agnew, A. M. Fearon, F. E. A. Wilson

IGC Proceedings (1977-2023)

Animal grazing performance at grass is predominately determined by herbage intake rates, with high yielding dairy cows requiring up to 20 kg/d DM within a limited grazing time (Gibb, 1998). Grass nutritional factors such as seasonal patterns in digestibility and water-soluble carbohydrate levels have been linked to animal productivity (Davies et al., 1991), while sward surface height, herbage mass, bulk density and green leaf mass have been shown to promote high grazing intake (Barrett et al., 2001). Furthermore, fatty acid profiles have been shown to improve the unsaturated fatty acid composition of milk, with potential human health benefits …

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The Nutritional Value Of Cocksfoot (Dactylis Glomerata L.) And Perennial Ryegrass (Lolium Perenne L.) Under Leaf-Stage Based Defoliation Management, L. R. Turner, D. J. Donaghy, P. A. Lane May 2023

The Nutritional Value Of Cocksfoot (Dactylis Glomerata L.) And Perennial Ryegrass (Lolium Perenne L.) Under Leaf-Stage Based Defoliation Management, L. R. Turner, D. J. Donaghy, P. A. Lane

IGC Proceedings (1977-2023)

The perception that cocksfoot is of lower nutritional value and less productive than perennial ryegrass is largely the result of studies in which management was based on perennial ryegrass (to the detriment of cocksfoot) or involved defoliation of both species at the same time (Greenhalgh & Reid, 1969; Johnson & Thomson, 1996). Maintaining plants in a vegetative state through species-specific management is essential to retain the high quality and productivity of cocksfoot. Defoliation at or before 4-5 fully expanded live leaves per tiller is recommended as the ideal physiological regrowth stage for defoliation of cocksfoot, resulting in metabolisable energy (ME) …

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Effect Of Ferulic Acid Esterase Enzyme Application On The In Vitro Digestibility And In Situ Rumen Degradability Of Tropical Grasses, Adegbola T. Adesogan, N. Krueger, C. R. Staples, D. B. Dean, W. Krueger May 2023

Effect Of Ferulic Acid Esterase Enzyme Application On The In Vitro Digestibility And In Situ Rumen Degradability Of Tropical Grasses, Adegbola T. Adesogan, N. Krueger, C. R. Staples, D. B. Dean, W. Krueger

IGC Proceedings (1977-2023)

Tropical grasses are the primary staple diet of most of the domesticated ruminants in the tropical and subtropical regions of the world. However, dry matter (DM) digestibility (DMD) and intake levels of these C4 grasses are considerably low, partly because of high lignin contents. Ferulic acid also impedes fibre digestion in such forages due to formation of cross linkages with digestible xylans. Certain esterase enzymes have been shown to cleave ferulic acid cross linkages in wheat bran but no studies have examined whether such enzymes can be used to increase the digestion of tropical grasses. Therefore, the objective of …

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Influence Of Internode Length On Degradability Of Lucerne Stems, H. G. Jung, F. M. Engles, J. F. S. Lamb May 2023

Influence Of Internode Length On Degradability Of Lucerne Stems, H. G. Jung, F. M. Engles, J. F. S. Lamb

IGC Proceedings (1977-2023)

Lignification of plant tissues restricts degradation of forages by ruminants. The undegradable lignified middle lamella/primary cell wall prevents rumen microbes from accessing undamaged adjacent plant cells. In contrast, walls of non-lignified tissues are completely degradable. Preliminary observations of how deeply rumen microbes could degrade different tissues within 20- to 30-mm long lucerne (Medicago sativa L.) stem pieces indicated a two-fold range in depth of degradation among stem samples. Studies were undertaken to determine if extent of cell wall degradation in lucerne was influenced by length of stem internodes.

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Mating Ewes On Condensed Tannin-Containing Forages Increases Ewe Reproductive Rate And Reduces Lamb Mortality, T. N. Barry, C. A. Ramirez-Restrepo, E. L. Mcwilliam, N. Lopez-Villalobos, P. D. Kemp May 2023

Mating Ewes On Condensed Tannin-Containing Forages Increases Ewe Reproductive Rate And Reduces Lamb Mortality, T. N. Barry, C. A. Ramirez-Restrepo, E. L. Mcwilliam, N. Lopez-Villalobos, P. D. Kemp

IGC Proceedings (1977-2023)

Action of condensed tannin (CT) reduces forage protein degradation in the rumen and increases the absorption of amino acids from the small intestine (Barry & McNabb 1999). This paper reports the effects of grazing ewes on two CT-containing forages during mating upon ewe reproductive rate and lamb mortality.

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Ruminal Proteolysis In Forages With Distinct Endopeptidases Activities, G. Pichard, C. Tapia, R. Larraín May 2023

Ruminal Proteolysis In Forages With Distinct Endopeptidases Activities, G. Pichard, C. Tapia, R. Larraín

IGC Proceedings (1977-2023)

Improving livestock efficiency in utilization 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.

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Polyphenol Oxidase Activity And In Vitro Proteolytic Inhibition In Grasses, J. M. Marita, R. D. Hatfield, G. E. Brink May 2023

Polyphenol Oxidase Activity And In Vitro Proteolytic Inhibition In Grasses, J. M. Marita, R. D. Hatfield, G. E. Brink

IGC Proceedings (1977-2023)

Harvesting and storing high quality forage in the cool humid regions remains a challenge due to the potential for protein degradation during ensiling. Red clover is an exception as high protein levels are maintained during ensiling. Decreased proteolytic activity in red clover is due to polyphenol oxidase (PPO) activity and appropriate o-diphenol substrates (Jones et al., 1995, Sullivan et al., 2004). This project was undertaken to determine if PPO activity is present in a range of grasses and the potential role in proteolytic inhibition in the presence of the o-diphenol caffeic acid.

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The Death Of Plants In Animals, M. K. Theodorou, A. Kingston-Smith, P. Morris May 2023

The Death Of Plants In Animals, M. K. Theodorou, A. Kingston-Smith, P. Morris

IGC Proceedings (1977-2023)

It is necessary first to understand some of the basic concepts associated with the digestion of the plant biomass within the rumen when considering mechanisms for altering/enhancing N-conversion efficiency in the forage-fed ruminant. Although it is generally assumed that breakdown of plant proteins in the rumen is mediated by microbial enzymes, there is increasing evidence to suggest that both plant and microbial proteases are active during degradation of ingested fresh forage (Beha et al., 2002; Kingston-Smith & Theodorou, 2000; Kingston-Smith et al., 2003, 2004). After fresh plant biomass enters the rumen and prior to extensive plant cell wall …

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