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Articles 1591 - 1620 of 16391

Full-Text Articles in Agronomy and Crop Sciences

Production De Viande Bovine Et Ovine Sur Prairie Dans Les Monts Sudetes, Janina Fatyga Jun 2025

Production De Viande Bovine Et Ovine Sur Prairie Dans Les Monts Sudetes, Janina Fatyga

IGC Proceedings (1977-2023)

Par suite du depeuplement des villages et de !'abandon de la culture dans des zones situees en altitude dans !es Sudetes, on y observe l'accroissement de la superficie des paturages perma­nents. Des 1968, on y cree des zones de pature OU en ete de jeu­nes bovins et des ovins provenant des fermes situees plus bas sont conduits en permanence. L'importance du phenomene est illustre par le fait qu'a present, sur le terrain d'une seule region de Walbrzych, il y a 103 bases de pature d'une superficie de 7.000 ha, appartenant a 54 fermes d'etat ou paissent environ 25.000 ovins et …


A Standard Livestock Unit (Slu) For Defining Stocking Rate In Grazing Studies, D J. Minson, P C. Whiteman Jun 2025

A Standard Livestock Unit (Slu) For Defining Stocking Rate In Grazing Studies, D J. Minson, P C. Whiteman

IGC Proceedings (1977-2023)

The weight of animals and hence their intakes vary between grazing experiments and at different stages of the same study but the results are often presented as though these differences do not affect grazing pressure (Roberts, 1980). Thus we have sheep/ha and cattle/ha, with no indication of the effects that differences in intake and hence grazing pressure might have on the pasture/animal interaction. Pastures are utilized by different classes of stock and there is a need to have a common basis for comparing their productivity. These problems would be over­come by the use of a Standard Livestock Unit (SLU).


Temporal Changes In Soil Organic Carbon And Other Near-Surfacesoil Properties Under Native Tallgrass Prairie In The Arkansasriver Valley, Katie Jansson, Kristofor R. Brye, Mike Richardson, Lisa S. Wood Jun 2025

Temporal Changes In Soil Organic Carbon And Other Near-Surfacesoil Properties Under Native Tallgrass Prairie In The Arkansasriver Valley, Katie Jansson, Kristofor R. Brye, Mike Richardson, Lisa S. Wood

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

One climate-change mitigation pathway is soil carbon (C) sequestration. Native prairies have long been known for their soil C sequestration abilities, but the full extent of their sequestration capacity is not completely understood, particularly across diverse regions. This study evaluated the effects of soil depth and soil map unit-prairie combination on changes in various soil properties from 2018 to 2022 in the top 20 cm of two native tallgrass prairies in west-central Arkansas. Soil bulk density, pH, electrical conductivity, total nitrogen, total C (TC), soil organic matter (SOM), and Mehlich-3 extractable soil nutrients were evaluated from the 0- to 10-cm …


Electric Weed Control—How Does It Compare To Conventional Weed Control Methods?, Catherine Borger, Miranda J. Slaven Jun 2025

Electric Weed Control—How Does It Compare To Conventional Weed Control Methods?, Catherine Borger, Miranda J. Slaven

Journal articles

Weed management practices in agroecosystems mainly rely on herbicide, mowing, or tillage. Electric weed control offers a novel alternative, with a range of commercially available products for weed management in agricultural environments. However, electrical weed control efficacy has not been effectively compared with conventional weed management practices. Further, electrical weed control products may have a fire risk, as highlighted but not assessed in prior studies. The current study evaluated an electric weed control machine (Zasso™ XPower) for weed management in four vineyard sites (in 2022 and 2023) in comparison to mowing and herbicide applications. Weed control tactics were applied in …


Effects Of Water Deficit Stress And Mycorrhiza, Azotobacter Chroococcum, And Azospirillum Lipoferum Biofertilizers On Yield And Morphological Traits Of Wheat (Triticum Aestivum L.) Cultivars, Mehdi Rashnou, Farshid Aref, Bahram Amiri, Masoud Rafiee, Mahdi Zare Jun 2025

Effects Of Water Deficit Stress And Mycorrhiza, Azotobacter Chroococcum, And Azospirillum Lipoferum Biofertilizers On Yield And Morphological Traits Of Wheat (Triticum Aestivum L.) Cultivars, Mehdi Rashnou, Farshid Aref, Bahram Amiri, Masoud Rafiee, Mahdi Zare

The Philippine Agricultural Scientist

Crop production in various parts of Iran faces significant constraints due to insufficient water availability, which is a major challenge to agricultural productivity. To study the effects of water deficit stress on shoot and root growth characteristics and seed yield of different wheat (Triticum aestivum L.) cultivars, an experiment was conducted using a randomized complete block design with a split-plot arrangement and 3 replications. The main factor was irrigation treatments (full irrigation during the growing season [S1], water withholding after flowering [S2], and water withholding after grain filling at the milk stage [S3]). The secondary factors were wheat cultivars …


Summaries Of Arkansas Cotton Research 2024, Fred M. Bourland Jun 2025

Summaries Of Arkansas Cotton Research 2024, Fred M. Bourland

Arkansas Agricultural Experiment Station Research Series

Planted cotton acreage in Arkansas increased in 2024 to 670,000 planted acres, which was 160,000 acres more than in 2023 when Arkansas producers planted approximately 510,000 acres of cotton. A wet spring, and two hurricanes in three weeks in late summer/early fall led to a slight decrease in harvested acres that culminated in a final number of 640,000 (https://www.nass.usda.gov/Quick_Stats/Ag_Overview/stateOverview.php?state=ARKANSAS). Producers harvested 640,00 acres of cotton, which ranked third nationally, behind Texas and Georgia (https://downloads.usda.library.cornell.edu/usda-esmis/files/k3569432s/nk324887m/qn59s0097/cropan25.pdf). The total harvested acreage is the greatest amount since 680,000 acres in 2011. The average cotton yield in Arkansas in 2024 was …


Arkansas Corn And Grain Sorghum Research Studies 2024, Jason Kelley, Travis Faske Jun 2025

Arkansas Corn And Grain Sorghum Research Studies 2024, Jason Kelley, Travis Faske

Arkansas Agricultural Experiment Station Research Series

The 2024 edition of the Arkansas Corn and Grain Sorghum Research Studies Series includes research results on topics pertaining to corn and grain sorghum production, including weed, disease, nematode, and insect management; economics; irrigation; agronomics; soil fertility; drone use; and research verification program results.

Our objective is to capture and broadly distribute the results of research projects funded by the Arkansas Corn and Grain Sorghum Board. The intended audience includes producers and their advisors, current investigators, and future researchers. The Series serves as a citable archive of research results.

The reports inform and guide our long-term recommendations, but should not …


Lethal And Sublethal Effects Of Cotton Expressing Single And Pyramided Proteins Of Bacillus Thuringiensis (Bt) On Helicoverpa Armigera (Lepidoptera: Noctuidae), Spodoptera Litura (Lepidoptera: Noctuidae), And Spodoptera Frugiperda (Lepidoptera: Noctuidae), Sharna Holman, Paul Grundy, Helen Spafford, Michael Furlong May 2025

Lethal And Sublethal Effects Of Cotton Expressing Single And Pyramided Proteins Of Bacillus Thuringiensis (Bt) On Helicoverpa Armigera (Lepidoptera: Noctuidae), Spodoptera Litura (Lepidoptera: Noctuidae), And Spodoptera Frugiperda (Lepidoptera: Noctuidae), Sharna Holman, Paul Grundy, Helen Spafford, Michael Furlong

Grain and Other Field Crops Research Articles

The susceptibility to proteins from Bacillus thuringiensis (Bt) can vary among lepidopteran pest species. While Bollgard 3 cotton (BG3) effectively controls the primary pest Helicoverpa armigera (Hübner) in Australia, its effectiveness against other pests, such as Spodoptera litura (Fabricius) and Spodoptera frugiperda (J. E. Smith), is unknown. This laboratory study assessed the survival and development of H. armigera, S. litura, and S. frugiperda larvae when fed foliage from a non-transgenic cotton variety (CC) and 3 transgenic cotton varieties: Bollgard (BG1) expressing Cry1Ac, Bollgard II (BG2) expressing Cry1Ac and Cry2Ab, and Bollgard 3 (BG3) expressing Cry1Ac, Cry2Ab, and Vip3A. Pyramided …


Climate Resilience For Organic Vegetable Growers In The Midwest: Views, Needs, And Priorities Of Technical Service Providers, Natalie Hoidal, Greta Gramig, James Dedecker, Nicholas Frillman, Katie Black, Sarah Hayward, Rue Genger May 2025

Climate Resilience For Organic Vegetable Growers In The Midwest: Views, Needs, And Priorities Of Technical Service Providers, Natalie Hoidal, Greta Gramig, James Dedecker, Nicholas Frillman, Katie Black, Sarah Hayward, Rue Genger

Journal of Extension

As organic vegetable production becomes increasingly important in Upper Midwest food systems, Extension programs and partners must rise to the challenge of supporting growers with climate resilience. These growers are uniquely vulnerable to climate impacts, and addressing this challenge requires a networked approach. We report on a needs assessment and social network analysis process with technical service providers across the region to define the challenges, needs, and opportunities for building individual and institutional capacity to address climate change with growers. Results highlighted several focus areas, including improved communication, better access to funding, sound information, and cultural appropriateness.


Cover-Crop Effects On Near-Surface Soil Physical Properties,Infiltration, And Nematodes Over Time In The Lower Mississippiriver Valley, Cooper Fanning, Kristofor R. Brye, Mike Daniels, Trenton L. Roberts, Sam Fernandes, Lisa Wood May 2025

Cover-Crop Effects On Near-Surface Soil Physical Properties,Infiltration, And Nematodes Over Time In The Lower Mississippiriver Valley, Cooper Fanning, Kristofor R. Brye, Mike Daniels, Trenton L. Roberts, Sam Fernandes, Lisa Wood

Crop, Soil and Environmental Sciences Faculty Publications and Presentations

Human population growth and climate change are stressors that continue to put pressure on current agricultural production systems. Cover crops (CC) as a means to improve soil health remain widely underused, particularly in the Lower Mississippi River Valley. The objective of this study was to evaluate the effects of CC on the change over time in near-surface bulk density, aggregate stability, total infiltration and steady-state infiltration rate, and nematode populations in eastern Arkansas. Averaged across depth, bulk density did not change over time under a no cover crop (NCC) treatment, but increased approximately 0.03 g cm-3 over time under CC. …


Changes In Elephantgrass Plant Components With Maturity: 1. Percentage Dry Yield, P Mislevy, F G. Martin, M B. Adjei May 2025

Changes In Elephantgrass Plant Components With Maturity: 1. Percentage Dry Yield, P Mislevy, F G. Martin, M B. Adjei

IGC Proceedings (1977-2023)

Elephantgrass (Pennisetum purpureum Schum.) biomass can be a source of energy for tropical regions of the world because of its high dry matter production (Mislevy et al., 1986 ; Prine et al., 1987). Research has shown the production of energy (meth­ane) from biomass can be best understood through systems analysis methodology that integrates the availability of land, climate, production inputs, plant quality, etc. To assess avail­able technology and identify information gaps Biomass to Methane (Biomet) models have been developed to determine the impacts of basic growth processes in response to the crops environment (Mishoe et al., 1987). Biomass growth …


Teneurs En Constituants Parietaux Et En Matieres Azotees Des Ligneuz Fourragers D'Afrique Occidentale, A R. Kone, D Richard, H Guerin May 2025

Teneurs En Constituants Parietaux Et En Matieres Azotees Des Ligneuz Fourragers D'Afrique Occidentale, A R. Kone, D Richard, H Guerin

IGC Proceedings (1977-2023)

Dans !es pays intertropicaux d'Afrique, l'elevage est surtout extensif et l'alimentation du betail est essentiellement basee sur le paturage nature! ou la strate ligneuse (arbres, arbustes) fournit des fourrages verts pendant la periode seche de l'annee, periode pendant laquelle le tapis herbace est sous forme de paille sur pied. Les ligneux sont done tres importants dans l'alimentation des ruminants domestiques et ii est necessaire d'en connaitre la composition chimique comme dans le cas des fourrages herbaces.


Evaluation Of Tree Legumes Species At Different Agroclimatic Zones Of Indonesia, Mas'ud Panjaitan, R Jessop, W W. Stur May 2025

Evaluation Of Tree Legumes Species At Different Agroclimatic Zones Of Indonesia, Mas'ud Panjaitan, R Jessop, W W. Stur

IGC Proceedings (1977-2023)

The population of Indonesia is over 145 million and more than 56 % of them earn their living from agriculture (Bi. Stat. Ind., 1983). A major problem in the development of improved animal production has been the shortage of feed and the generally low nutritive value of tropical forages which limit livestock pro­duction in Indonesia (Asian Agriculture Survey, 1969). The production of feed of adequate quality for ruminants is an important consideration particularly for small holders. In many situations, nitrogen fixing legume trees can be used as a high protein feed supplement which improves the utilization of grasses and crop …


Valeur Nutritive D'Un Parcours Mixte A Acacia Cyanophylla, Atriplex Nummularia Et Medicago Arborea, Y Saadani, C Kayouli May 2025

Valeur Nutritive D'Un Parcours Mixte A Acacia Cyanophylla, Atriplex Nummularia Et Medicago Arborea, Y Saadani, C Kayouli

IGC Proceedings (1977-2023)

II existe tres peu de donnees concernant la valeur nutritive des arbustes fourragers ; les rares etudes realisees en Tunisie ont porte surtout sur leur productivite, la charge animale et sur leur appetence (Hamrouni et Sarson, 1975; Ben Boubaker, 1985). L'objectif de ce travail est d'etudier la valeur nutritive des feuilles et brindilles d' Acacia cyanophylla, d' A triplex nummula­ria et de Medicago arborea ainsi que leur contribution dans la ration de caprins et d'ovins.


Utilization Of Native Mediterranean Fodder Trees By Dairy Goats, M Meuret May 2025

Utilization Of Native Mediterranean Fodder Trees By Dairy Goats, M Meuret

IGC Proceedings (1977-2023)

Few data are available on utilization of fodder trees and shrubs by lactating goats. In most cases, predictions of animal performances on the basis of recommendations obtained from standard reference trials, do not correspond with production results achieved on the farm. Using measurements in digesti­bility cages and on rangelands (chromic oxide marker), we recorded intake, apparent digestibility of diets and perform­ances of goats well used to rangelands and browsing fresh oak foliage (Quercus ilex and Quercus pubescens).


Phenols As Defensive Compounds In Birch (Betula Spp.) Metabolism Of Platyphylloside In Goats, Rabbits And Hares, R T. Palo, G Iason, P G. Knutsonn May 2025

Phenols As Defensive Compounds In Birch (Betula Spp.) Metabolism Of Platyphylloside In Goats, Rabbits And Hares, R T. Palo, G Iason, P G. Knutsonn

IGC Proceedings (1977-2023)

Herbivores of the boreal forest like moose (Alces alces), hares (Lepus spp.) and birds (Tetranoidae) use birch as a major feed source. The tree is of medium preference to the animals and is low in available nutrients for most of the year. Apart from a high amount of lignified cell walls it also contains con­siderable amounts oflow molecular phenolic substances (Palo, 1984). A herbivore feeding on birch could thus be excepted to ingest large amounts of phenols. These are in general enough fat soluble to enter animal cells expected to ingest large amounts of …


Forage Production And Nutritive Value Of Leucanea Leucoephala In Southern Puerto Rico, L E. Tergas, R Milton Martinez, A V. Mendez Cruz May 2025

Forage Production And Nutritive Value Of Leucanea Leucoephala In Southern Puerto Rico, L E. Tergas, R Milton Martinez, A V. Mendez Cruz

IGC Proceedings (1977-2023)

Leucaena leucocephala (L.) is a perennial schrub native to Mexico, Central America and the Caribbean, considered by investigators as a valuable forage legume because of its capacity for high production of digestible forage with a high protein content and tolerance to drought in semiarid regions with annual rainfall less than 1,000 mm (Skerman, 1977). The soil fertility of the semiarid region in southern Puerto Rico is adequate, but rainfall distribution is limiting for forage production and nutritive value. There is a demand for a suit­able and inexpensive source of high quality forage to improve the diet of the grazing cattle …


Effect Of Chemical Composition Of Roughages On Their Degradation Characteristics In The Rumen And Their Relationship With The < In Vitro > Organic Matter Digestibility, S Lopez, Dolores Carro, J S. Gonzales, Conchita Carpintero May 2025

Effect Of Chemical Composition Of Roughages On Their Degradation Characteristics In The Rumen And Their Relationship With The < In Vitro > Organic Matter Digestibility, S Lopez, Dolores Carro, J S. Gonzales, Conchita Carpintero

IGC Proceedings (1977-2023)

The microbial fermentation of feeds in the reticulo-rumen allows ruminants the utilization of feeds with amounts of cell wall components, i.e. roughages. This rumen fermentation can be affected by the feed chemical composition and numerous techniques have been developed for its determination (Van Soest, 1982). The objective of the present work is to investigate the effect of the chemical composition of forages preserved under differ­ent methods on their degradation characteristics in the rumen determined by the « in sacco » method and to study the rela­tionships between the « in vitro» organic matter digestibility (IVOMD) and the rumen degradability.


Rumen Degradation Of Various Grass Species At Different Stages Of Growth, L J. Halliday May 2025

Rumen Degradation Of Various Grass Species At Different Stages Of Growth, L J. Halliday

IGC Proceedings (1977-2023)

The species and cultivars sown depends on the farming sys­tem practiced. These developing swards are however, always invaded by native species including Agrostis, Paa and Festuca spp. which are generally referred to as 'weed' grasses. While the merits of Lolium spp. are well documented (Minson et al. 1960; Norton, 1982) information on the weed grasses is limited (Hag­gar, 1976). The potential for milk and meat production is dependent on the supply of utilizable nutrients to the animal's tissues which in turn is largely governed by the ability of rumen microbes to degrade plant cell walls. Although the degradability of dry …


Apparent Digestibility, Dynamics Of Rumen Fermentation And Sites Of Digestion Of Hays Of Leucaena Leucocephala (Lam) De Wit Cv. Peru, N M. Rodreiguez, I Borges May 2025

Apparent Digestibility, Dynamics Of Rumen Fermentation And Sites Of Digestion Of Hays Of Leucaena Leucocephala (Lam) De Wit Cv. Peru, N M. Rodreiguez, I Borges

IGC Proceedings (1977-2023)

Protein deficiency, among others, is a common problem for livestock production in tropical regions. The use oflegumes has been suggested as a solution and Leucaena leucocephala has shown a great potential due to its capacity of nitrogen (N) fix­ation and dry matter (DM) production (NAS, 1984). However, very little is known about its nutritive value regarding its protein-energy balance and the process of digestion. The present work aimed the evaluation of the nutritive value of hays of Leucaena leucocephala cut at two stages of growth, through trials of apparent digestibility, dynamics of rumen fer­mentation and partition of digestion.


In Situ Degradation Of Cell Wall Neutral Sugars Of Normal And Brown Midrib Sorghum X Sudangrass Hybrids, K J. Moore, J O. Fritz, E H. Jaster May 2025

In Situ Degradation Of Cell Wall Neutral Sugars Of Normal And Brown Midrib Sorghum X Sudangrass Hybrids, K J. Moore, J O. Fritz, E H. Jaster

IGC Proceedings (1977-2023)

The nutritive value of forage for ruminants is limited by the digestibility of the complex polysaccharides cellulose and hemicellulose by rumen microbes. In grasses, the polysacchar­ide fraction of the cell wall is composed largely of polymers of neutral sugars and to a lesser extent uronic acids. Cellulose is a high molecular weight linear polymer of B-1 ➔ 4) linked D­gluco-pyranose units. Hemicellulose is a complex mixture of linear and branched-chain heteropolymers containing xylose, arabmose, mannose, galactose, glucose, and uronic acids (Van Soest, 1982). Lignification of the cell wall is a primary factor limiting the digestion of cell wall polysaccharides. Close …


Feed Evaluation Using Mobile Dacron Bags And Influences Of The Diet Composition, H Anzola, F N. Owens May 2025

Feed Evaluation Using Mobile Dacron Bags And Influences Of The Diet Composition, H Anzola, F N. Owens

IGC Proceedings (1977-2023)

The Mobile Nylon Bag (MNB) technique has been used successfully in protein nutrition studies with swine (Sauer et al., 1983) to determine amino acid availability from protein in specific feedstuffs. Canadian researchers also have tested this technique to predict site of digestion in ruminants (Kirkpatrick and Kennelly, 1987). Differences in small intestinal digestion may explain why animal responses differ to dietary protein sources which have similar ruminal escape values (Owens, 1986). The MNB holds promise to appraise the intestinal avail­ability of undegraded dietary protein though further develop­mel).t and testing are needed. The objective of this experiment was to examine the …


Prediction Of Digestibility And Protein From Growing Degree-Days For Crested And Western Wheatgrass, A` B. Franck, J F. Karn May 2025

Prediction Of Digestibility And Protein From Growing Degree-Days For Crested And Western Wheatgrass, A` B. Franck, J F. Karn

IGC Proceedings (1977-2023)

Morphological development of crops, including cool-season forage grasses, is mainly a function of air temperature. Mor­phological development of plants has been predicted from ther­mal units expressed as growing degree-days (GDD) (Franck, 1985 ; Wang, 1960). The use of thermal units also provides a predictive measure for managing forages based on growth stages rather than dates. However, forage digestibility ��nd crude protein (CP) content generally decrease as morphological development and time increase (Kamstra, 1973 ; Kilcher and Troelsen, 1973). The relationship between thermal units and forage digestibility and CP has not been defined for crested and western wheatgrasses. The primary purpose …


Forage Quality Of Coast Cross 1 Bermudagrass On Intestinal Digestion Of Dietary Amino Acids, G Coto, Hanna Meier, Patrica Malgarez May 2025

Forage Quality Of Coast Cross 1 Bermudagrass On Intestinal Digestion Of Dietary Amino Acids, G Coto, Hanna Meier, Patrica Malgarez

IGC Proceedings (1977-2023)

The aim of this work was to study the digestibility of dietary amino acids found in the fibrous material, considering the qual­ity of the forage offered as the sole feeding source.


Sites Of Digestion Of Nitrogen Of Hays Made With The Tropical Legume Neonotonia Wightii, R R. Vera, E A. Pizarro, A Toscano, N M. Rodriguez May 2025

Sites Of Digestion Of Nitrogen Of Hays Made With The Tropical Legume Neonotonia Wightii, R R. Vera, E A. Pizarro, A Toscano, N M. Rodriguez

IGC Proceedings (1977-2023)

Tropical pasture species are of well-known lower quality than temperate species and there is evidence that some tropical legumes may contain antiquality factors that reduce further their nutritive value. Nonetheless, the nutritive value of Neonotonia wightii is generally moderate to high (Pizarro et al., 1983 ; Ribeiro et al., 1980), although there is little information on the factors that affect its quality, and none on the rate and sites of digestion within the gastrointestinal tract of ruminants. The aim of the work reported here was to examine the effect of age on the chemical composition, apparent digestibility and sites of …


Kinetic Study Of The Rumen Microbial Degradation Of Lucerne And Italian Ryegrass Observed By Scanning Electron Microscopy, E Grenet, J Jamot May 2025

Kinetic Study Of The Rumen Microbial Degradation Of Lucerne And Italian Ryegrass Observed By Scanning Electron Microscopy, E Grenet, J Jamot

IGC Proceedings (1977-2023)

For the same digestibility cell wall contents of legumes and grasses differ ; their histological structure is not the same and this may account for the differences in rumen degradation. We studied by scanning electron microscopy (SEM) the histologi­cal structure of these plants with regard to stages of maturity, and their kinetic degradation in the rumen.


Fermentation Characteristics Of Temperate Forage Stems Digested In Vitro, D R. Buxton May 2025

Fermentation Characteristics Of Temperate Forage Stems Digested In Vitro, D R. Buxton

IGC Proceedings (1977-2023)

Digestion of herbage by ruminants is limited primarily by concentration of neutral-detergent fiber (NDF) in herbage and degradability of this cell-wall material. Because mature stems usually contain more NDF than immature stems or leaves the proportion of stems approaching maturity is normally' the dominant morphological factor that determines digestibility of herbage (Buxton and Hornstein, 1986). On the basis of digesti­bility, NDF can be divided into two fractions: potentially digestible NDF (PDNDF) and indigestible NDF (IDNDF; Mertens and Ely, 1982), which is not digested regardless of length of fermentation. Digestion of NDF can be characterized by a two-stage process involving a …


Nitrogen And Organic Matter Disappearance In The Digestive Tract Of Sheep Grazing Three Winter Foggages, W A. Van Niekerk, H H. Meissner, E B. Spreeth, I S. Conradie May 2025

Nitrogen And Organic Matter Disappearance In The Digestive Tract Of Sheep Grazing Three Winter Foggages, W A. Van Niekerk, H H. Meissner, E B. Spreeth, I S. Conradie

IGC Proceedings (1977-2023)

Animal production in the tropics and subtropics is limited by poor intake. This results because of high cell wall content and poor digestibility of tropical forages (Minson & McLeod, 1970). During the dormant (winter) season these negative effects were exaggerated. Also, N declines resulting in a further reduction in intake. The questions addressed here were whether winter foggage of improved subtropical pastures could be ben­eficial and secondly, how three species adapted to the drier areas of South Africa, compare in this regard.


Nutritive Value Of Perennial Ryegrass Swards Grazed By Sheep In Autumn In The Uk, J A. Milne, H Dove, A M. Sibbald May 2025

Nutritive Value Of Perennial Ryegrass Swards Grazed By Sheep In Autumn In The Uk, J A. Milne, H Dove, A M. Sibbald

IGC Proceedings (1977-2023)

A knowledge of the nutrient supply from grazed herbage for ewes in the autumn in N. Europe is required to predict the consequences for their subsequent reproductive performance. Herbage intake has been found to be positively related to sward height over this period at low sward heights but there is no information over a wider range of heights, on the amounts of non-ammonia nitrogen (NAN) available for absorption in the small intestine nor on the digestion of organic matter in the rumen. Experiments on frozen or artificially dried herbage harvested in the autumn have given variable results for the amounts …


Influence Due Niveau De Fertilization Azotee Sur La Degradabilite De L'Azote De La Fetuque Elevee Recoltee En Vert, P Le Goffe, R Verite, G Lemaire May 2025

Influence Due Niveau De Fertilization Azotee Sur La Degradabilite De L'Azote De La Fetuque Elevee Recoltee En Vert, P Le Goffe, R Verite, G Lemaire

IGC Proceedings (1977-2023)

Il est connu que la fertilisation azotee ameliore non seule­ment la biomasse produite mais aussi la teneur en azote de la plante; cependant certains auteurs la soup9onnent de reduire le flux d'azote duodenal (Armstrong, 1974). Cette diminution de la valeur azotee reelle pourrait s'expliquer par la baisse des syntheses de proteines microbiennes et/ou !'augmentation de la degradation ruminale des proteines de l'herbe. Dans ce travail, l'effet de 2 niveaux de fertilisation azotee, appliques sur 4 cycles successifs d'une fetuque, sur la degradabilite de l'azote de la plante verte a ete etudie par 3 methodes differentes ; de plus l'incidence du …