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Etude D'Un Facteur Antinutritionnel De La Luzerne: Les Saponines, M Lila, G Genier, W Pietraszek

IGC Proceedings (1977-2023)

Les proteines de luzerne (Medicago sativa) extraites par des procedes industriels ne peuvent etre incorporees qu'en faible proportion dans les rations pour monogastriques a cause d'un effet antinutritionnel du essentiellement a la presence de sapo­nines et plus particulierement d'acide medicagenique (Pie­traszek, 1985). La technologie d'extraction ne permettant pas d'eliminer ces molecules, il a ete envisage d'ameliorer la qualite de ces proteines extraites par la diminution de la teneur dans la plante par voie genetique. Pour cela il fallait etudier la variabilite genetique disponible au sein de l'espece Medicago sativa et definir un test rapide per­mettant de discriminer en grande serie …

Mineral Composition Of Grasses Grown On Peat Soils In Northwestern Hungary And Fertilization Experiments. Manganese, R Schmidt, J Varga, G Tolgyesi

IGC Proceedings (1977-2023)

The main goal of these experiments which were carried out for four years was to study the mineral composition of grasses grown on peat soil, where preliminary studies indicated manga­nese, copper and zinc deficiency. We tried to eliminate these deficiences by agrochemical methods, because in our opinion, intervening in the first part of the foodchain - in the soil - we can contribute to solving of the deficiency problems more fund­amentaly (Ti:ilgyesi et al., 1983).

Characterization Of Biological Properties Of Fodder Value Of Dandelion, Taraxacum Officinale Web., M Falkowski, I Kukulka, S Kozlowski

IGC Proceedings (1977-2023)

In recent years the quantities of dandelion appearing on newly established grasslands has increased quite significantly. In such conditions it can no longer be treated as a meadow herb whose fodder value, according to European literature, equals half of that of valuable fodder plants. Becoming a weed, dan­delion has been the object of investigations on ways of elimina­ting it from the sward by means of herbicides (Schlotter et al., 1988). At the same time, experiments are under way on biologi­cal properties of dandelion with the aim to explain the causes of its expansion. It was found that there is an …

Location Of Polyphenols In Leaves Of Serciea Lespedeza, C O'H Mosjidis, C M. Peterson, J A. Mosjidis

IGC Proceedings (1977-2023)

Preliminary studies in sericea lespedeza, a nonbloating for­age legume, indicated that its palatability and digestibility were reduced by high levels of phenolics (Clarke el al., 1939). Another study suggested that younger parts of the shoots are more palatable than older leaves and stems (Donnelly el al., 1971). Nevertheless, younger leaves have been reported to con­tain higher levels of phenolics (Burns, 1966). Polyphenols have been thought to play a role as growth regulators and in protection against insects and diseases. Also they seem to be associated with lignification (Salatino el al., 1988). The present study was performed to determine whether his­tological …

Effect Of Endophytic Fungus Infection, Water Stress And Genotype On K, Ca And Mg Concentration Of Fescue, S R. Wilkinson, D P. Belesky, W C. Stringer

IGC Proceedings (1977-2023)

Replacement of endophyte infected tall fescue with endo­phyte free tall fescue is recommended to avoid tall fescue toxi­cosis. Fribourg et al. (1988) suggest that the endophyte may enhance tolerance of tall fescue to environmental stresses, including drought. This controlled environment study was undertaken to determine the effect of water stress on the K, Ca and Mg concentration of four genotypic selections of tall fescue with and without fungal endophytes. This paper emphasizes water stress and endophyte effects. The growth characteristics are reported elsewhere (Belesky et al. 1989).

Effect Of Fertilizers On Cutting On Time On Chemical Composition Of Sward From Permanent Meadow, A Golob, Zdenka Berloznik, M Leskosek, Vekoslava Stibilj

IGC Proceedings (1977-2023)

Ecological problems and surpluses of milk and meat have given rise to less intensive systems of grassland utilisation. One of such system is utilisation of air nitrogen via legume sym­biosis with nitrogen fixing bacteria. In Slovenia, where conditions for legume growth are more favourable than in NW Europe, natural meadows fertilized with P and K only give reasonable yields - on average around 7 t DM per ha (Leskosek, 1981). Most legumes suffer after fre­quent defoliation so such meadows should be defoliated only 2- 3 times during the growing season. Under less frequent cutting regime nutritive value of forage is …

The Effect Of N And K Fertilizers On The No3 Content Of Different Grass Species And Mixtures, A Szodfridt, J Varga

IGC Proceedings (1977-2023)

The major quantity of the annual grassland vegetation comes from the first cut in Hungary because of the continental climate of the country. Next to the energy content of grasses it is important to have informations about the amount of some possible toxic components such as nitrate. The critical NO3- value is considered to be 0.25-0.31 % in DM (Andreev, 1981), NO3 content higher than 0.6 % in DM is toxic (Kemp et al., 1977). Ebert et al. (1977) showed that 120 kg/ha N given for the 1st cut did not raise NO3 content higher than the critical value. K …

Determination Of Condensed Tannins In Tropical Legume Forages, L Telek

IGC Proceedings (1977-2023)

The effect of condensed tannins (proanthocyanidins) in ruminant nutrition is complex and needs further interdiscipli­nary reinvestigations with improved analytical methods. With the « cell rupture » theory of legume pasture bloat (Howarth et al., 1978), the role of condensed tannins seems to be secondary; they are acting as protein precipitants (Goplen et al., 1980) and inhibiting microbiological proliferation in cell­ular spaces (Howarth et al., 1982). Their assumed interference with digesting enzymes in vivo is doubtful (Mole and Water­man, 1985). On the importance of condensed tannins in nutrition, several reviews were published (McLeod, 1974; Tempel, 1982; Kumar and Singh, 1984 and …

Screening Sericea Lespedeza Germplasm For Tannin Concentration In The Leaves And Herbage Palatability, J C. Petersen, J A. Mosjidis, N S. Hill

IGC Proceedings (1977-2023)

Several million hectares in the subtropical world are currently used as grazing land for beef and dairy cattle, how­ever, in many cases animal production is very low. To improve animal nutrition, cultivated legume species can be introduced. Sericea lespedeza has potential and could be utilized in the acid soils of the· subtropics. Generally, sericea is low in palatability and nutritive value because its leaves contain tannins, which have long been associ­ated with low intake and reduced digestibility. Tannins are responsible for an astringent or bitter taste caused by the pre­cipitation of salivary glycoprotein (Goldstein and Swain, 1963). Chopping or macerating …

The Effect Of Selenium Fertilizer On The Selenium Status Of Sheep Grazing Annual Pasture In South-Western Australia, B R. Whelan, D W. Peter, N J. Barrow, D J. Buscall, V C. Cox

IGC Proceedings (1977-2023)

White muscle disease was first reported in grazing livestock in Western Australia by Gardiner (1961). Sheep affected by the disease could be divided into two categories : young suckling lambs in winter and early spring, and weaners and hoggets in summer (Gardiner et al., 1962). Subsequent investigations showed that, while there were few clinical symptoms of sel­enium deficiency, there were probably many sheep suffering from ill-thrift. This sub-clinical deficiency caused reduced liveweight gains, reduced wool production and lowered ewe fertility. It was most noticeable in areas of greater than 600 mm of annual rainfall on the lighter sandy soils with …

Synthesis Of Cell Wall Components In Maize Internodes, J H. Cherney, J J. Volenec, G A. Brown

IGC Proceedings (1977-2023)

Cell wall structure affects intake and digestibility of forages by rummants. Before microbial degradation of cell walls can be understood, it will be necessary to have a better understanding of cell wall formation. Internodes of grasses elongate in a_cropetal succession, with two internodes usually elongating s1multaneously. Elongating internodes consist of three regions : 1) a zone of cell division, 2) a zone of cell elongation, and 3) a zone of secondary cell wall deposition. This tissue provides an excellent system for studying cell wall changes in rapidly developing tissues. Our objectives were to : 1) examine changes in cell wall …

Natural And Artificial Drying Effects On Condensed Tannins Of Sericea Lespedeza, T H. University Of Georgia, W R. Windham, J J. Evans, C S. Hoveland

IGC Proceedings (1977-2023)

Sericea lespedeza [Lespedeza cuneata (Dumont-Cours.) G. Don.] is well adapted to acid soils and low fertility but has generally been considered a low-quality forage due to high levels of tannin and indigestible fiber. Tannin levels increase during midsummer (Windham et al. 1988). The most com­monly used assay for tannin in sericea is the vanillin-HCl pro­cedure (Burns, 1963) on oven-dried samples. Oven-drying has been reported to cause increased polymerization or oxidative changes in tannins (Goldstein and Swain, 1963). Fresh-frozen sericea contained higher amounts of extract­able tannin than field-dried forage and fiber digestibility of high-tannin sericea by sheep was much lower …

Restoring Exotic Cool-Season Grass Dominated Landscapes With Clethodim And Glyphosate, Eleanor J. Muzzy, Joshua D. Wiese, Abraham J. Kanz

Transactions of the Nebraska Academy of Sciences and Affiliated Societies

A major threat to grasslands around the world is the spread of exotic cool-season grasses (ECSG). ECSG dominate vegetative communities and degrade critical habitats. One of the most common methods to treat ECSG is herbicide. To compare how the widely-used, non-specific herbicide glyphosate compared to the grass-specific herbicide clethodim, we conducted a fall spray in November 2023 at two different sites located in the Central Platte River Valley of Nebraska. The following June, we used a modified Daubenmire frame sampling method to gather data on relative cover, species richness, and community composition. After analysis, glyphosate appeared to be more effective …

Grassland For Our World, F Riveros

IGC Proceedings (1977-2023)

The present-day role of grasslands and fodder is reviewed with respect agriculture, animal production and environmental concerns. The world 's grazing lands are a finite resource nnd, overall, are being badly mnnaEed; in most developing countries action is required now, before it is too lnte. They will continue to be a major source of animal feed for the foreseeable future; encroachment from cropping will con

Human Impact On Terrestrial Ecosytems- What We Know And What We Are Doing About It, H A. Mooney

IGC Proceedings (1977-2023)

At present the impact of humankind on the Barth System is substantial mul will become greater as we continue to add over 80 million people to the global population each year. Collectively the human species utilises over a third of the total fresh water that is available, as well as an equivalent amount of tho total terrestrial productivity. Possil energy is being consumed at a prodigious rnte and fuels, among other things, over a half a billion vehicles. To support the large human population the Earth has been greatly reconfigured with much of the land utilised for grazing and agriculture. …

Grasslands For Sustainable Ecosystems, Malcolm Hadley

IGC Proceedings (1977-2023)

Grasslnnds present many advantages for examining issues related to sustainability. Grasslands include planted pastures as well as a variety of natural rangelands in situations ranging from semi-arid to subhumid. Diversity is also reflected in the spectrum of grassland users and uses, for example, nomadic pastoralism, extensive ranches, intensive pastures, wildlife tourism, game hunting. And in terms of sustainability of resource management, grasslands encompass a wide range of contrasting situations and conflicts in resource use. Heavy grazing pressure associated with increasing human populations in certain tropical savannas, the implications of rural depopulation to traditional pasture management in alpine regions, and the …

Red Clover Hybrid Ryegrass Associations Results Obtained From 1984 To 1987 In Four French Regions, C Pfitzenmeyer, C Longueval

IGC Proceedings (1977-2023)

In France, red clover is often grown in association with a grass in order, if not to increase the yield of forage, at least to improve its quality by having a larger protein content in the harvested product. Among the grass species associated to red clover, Italian ryegrass, too aggressive a competitor, is replaced more and more by hybrid ryegrass. The aims of the present work were the following

1% to obtain quantitative references on the behaviour o[ hybrid ryegrass/red clover associations in four contrasting regions of France ;

2% to check that the presence of clover, through the transfer …

Potentials Of Summer Fodders Under Intensive Cropping System In India, M S. Tiwana, Thakur Singh

IGC Proceedings (1977-2023)

One of the reasons for low milk production in India is the non-availability of good quality fodders in sufficient quantity. Therefore, it is necessary to bridge the gap of this acute short­age of fodder for increasing the milk production. There seems to be no possibility of increasing area under fodders and the only alternative looks to be the ulilization of vacant land (70 days) after harvesting wheat and before the sowing of main summer season crops. However, the growing of these crops may have some effect on the yield of succeeding crops by depleting or replenishing the nutrient status of …

Competitive Effects On Production Of Lolium Perenne L. And Trifolium Alexandrinum L. In Mixture And Mono-Culture, M S. Tiwana, K P. Puri, I S. Thind

IGC Proceedings (1977-2023)

Berscem (Trifolium alexandrinum L.) is grown as a fodder crop by every farmer of north India. Though it is a very good multi-cul legume fodder, yet its dry matter percentage is low which indirectly affects the total dry matter production over a period of 6 to 7 months. Presently no suitable multicut grass for the same period is available which may be grown separately or in mixture with berseem to produce high dry matter yield. The first successful planting of ryegrass in research trials was made in 1976 (Tiwana and Puri, 1984) in India. After that, we became interested …

Herbage Yield Of Annual Ryegrass (Lolium Multiflorium Lam.) And Common Vetch (Vicia Sativa L.) At Different Seeding Rates, M A. Jimenez, O L. Gallegos, M.J L. Castrellon

IGC Proceedings (1977-2023)

Most of the dairy farms in the Central Valley of Mexico have alfalfa and corn silage as major forages. Winters are mild, how­ever, yield of alfalfa is reduced and no corn can be grown. For­age crops as oats, annual ryegrass and common vetch have been grown successfully to supply winter forage (Avendano, 1978; Victoria, 1981). Annual rycgrass generally outyields oats, but a high input of nitrogen is required by annual rye grass (Ciane, 1978). The high cost of N fertilizers prevents their use and cheaper N sources should be sought. Legumes as common vetch grown with annual ryegrass can be …