Weed Science Commons^™

Optimizing The Use Of Grazed Dryland Pasture In Western Oregon, T E. Bedell

IGC Proceedings (1977-2023)

When they are properly fertilized, western Oregon dryland pastures of subterranean dover with grasses such as perennial rp:g:rass, tall fescue, and resident annuals produce total annual dry-matter yields averaging 6,500 kg/ha. Some sites are capable of over 9,000 kg/ha. Optimum use of this forage is complicated by its highly seasonal availability. Over 50 % of the total growth occurs from late April to mid-June. Only about 10% takes place during autumn-early winter, and virtually none occurs during summer. Research shows livestock weight gains from 300 to over 700 kg/ha can be expected depending upon pasture mixture and kind of grazing …

Value Of Lucerne As A Grazing Supplement For Sheep Grazing Natural Pastures In A Semiarid Area Of Australia, D L. Michalk, G E. Robards, E A. Armstrong, J Lacy

IGC Proceedings (1977-2023)

In the central areas of New South Wales, the natural pastures are dominated by annual species that grow during the cooler months, producing good-quality grazing that is particularly abundant during spring. -However, these species mature rapidly in late spring and provide poor-quality summer grazing. The 4-year study reported here was designed to examine the value of sown lucerne, equivalent to one-third of the total area, as a supplement to be grazed mainly during late spring and summer. The availability of lucerne for spring grazing by ewes and lambs was of benefit only in one year when maturing grass seeds were …

Animal Production From Brazilian Tropical Pastures, G L. Rocha, V.B G. Alcantara, P B. Alcantara

IGC Proceedings (1977-2023)

This review deals with the potential for beef production from nitrogen- and legume-based pastures in tropical Brazil. Possibilities for impr􀀞ving the beef industry supported by grass-legume pastures are very promising. According to the literature examined, legume-based pastures produced an annual average of 329 kg gain/ha, and nitrogen (N) fertilization resulted in 4.56 kg gain/ha. Phosphorus (P) was the main fertilizer utilized in addition to N, followed by potassium (K), lime, and micronutrients. An­nual rainfall averaged 1430 mm. Grasses used were of the genera Melinis, Hyparrhenia, Panicum, Cenchrus, Digitaria, Cynodon, Brachiaria, and Pennisetum, and the legumes were of the genera Macroptilium, …

Effect Of Sheep And Cattle Grazing On A Mixed Pasture Of Perennial Ryegrass, Kikuyu, And White Clover, G J. Goold

IGC Proceedings (1977-2023)

Mixed pastlkes of perennial ryegrass (Lolium perenne L. ), kikuyugrass (Pennisetum clandestinum Hochst. ), and white clover (Trifolium repens L.) are commonly found within warm-zone areas of New Zealand but are frequently disliked because of prob­lems associated with kikuyugrass dominance. A grazing experiment was conducted to provide basic information on the response of such swards to grazing by cattle and sheep. The pastures were rotationally grazed with young sheep or cattle at two stocking levels each year from 1970 to 1975, with stocking rates adjusted twice yearly according to seasonal pasture growth. The pastures grazed by cattle …

Relationship Of Forage-Evaluation Techniques To The Intake And Digestibility Of Tropical Grasses, S M. Abrams, H Hartadi, C M. Chaves, J E. Moore, W R. Ocumpaugh

IGC Proceedings (1977-2023)

Seventy-six grass hays, harvested at 2, 4, 6, and 8 weeks of regrowth, were fed ad libitum to wethers in a digestibility and in­take trial. Range of organic-matter digestibility (OMD) was 54.l % to 72.3% and that of organic-matter intake (OMI) 17.3 to 27.4 g/kg. Lignin was the chemical component most highly related to OMD (r = - 0.72). Neutral detergent fiber (NDF) was bet­ter than acid detergent fiber (ADF) as a predictor of OMD (r = - 0.66 vs. - 0.45). In-vitro NDF digestibility (IVNDFD) was superior to in-vitro organic-matter digestibility (IVOMD) and all other analyses as a predictor …

Effect Of Feeding Level And Forage: Concentrate Ratio On The Digestibility Of Pelleted Diets By Sheep And Cattle, G.M J. Horton, M J. Farmer, B E. Melton, S Sklane

IGC Proceedings (1977-2023)

Sheep are frequently used to determine the nutritive value of cattle feeds. However, there is some evidence that digestion coef­ficients for cattle and sheep may differ and that digestibility may be influenced by feeding level. The purpose of this study was to investigate the effects of feeding level and animal species on the digestibility of pelleted diets containing different ratios of alfalfa hay to barley grain. Five 4O-kg yearling crossbred lambs and four 35O-kg yearling steers were used to evaluate each diet. The six diets were isonitrogenous, containing the following proportions of barley grain and alfalfa hay (percentage as fed …

Effect Of Solvent Treatments On Intake And Digestibility Of Corn Stover, D M. Schaefer, M R. Ladisch, C H. Noller, V L. Lechtenberg

IGC Proceedings (1977-2023)

Treatment of crop residues with low levels of sodium hydroxide has been shown to improve organic-matter digestibility and animal performance. One objective of these experiments was to evaluate the effects of three treatments -water, sodium hydrox­ide, and chelating metal cellulose-swelling solution-on solubilization of cell-wall components in corn (Zea m£rys) stover. The two latter treatments were balanced for level of sodium hydroxide application, which was .3 .2 % of stover dry matter. The second objective was to determine the effects of these treatments on in-vitro and in-vivo digestibility as well as on consumption of corn stover. Twelve growing ram lambs were …

Seed And Seedling Dynamics Of Annual Medic Pastures In South Australia, E D. Carter

IGC Proceedings (1977-2023)

Annual species of Medicago (i.e., medics) are the key to successful cereal-pasture rotations in the integrated crop-livestock farming systems on the neutral to alkaline soils of southern Australia. However, many medic stands have deteriorated in recent years. This deterioration has prompted research on the effects of grazing sheep on the seed-seedling dynamics of annual medic­based pastures in the Mediterranean environment of South Australia, aiming to quantify the impact of medic seed reserves in or on the soil upon pasture establishment and productivty.

Animal-house experiments involving the feeding of purepod and pod-chaff diets to sheep and a field experiment have been …

Physiology Of Growth Of A Grazed Sward, E L. Leafe, A J. Parsons

IGC Proceedings (1977-2023)

To improve our understanding of grassland utilization under grazing, the physiology of a grazed sward was investigated. An enclosure method, infrared gas analysis, and radiocarbon were used to measure sward and single-leaf photosynthesis and assimilate utilization. Intake by sheep was also measured. Expanding and recently expanded leaves had high rates of net photosynthesis but leaf sheaths, whose projected area in a "hard" grazed sward equaled that of the lamina, had low efficiency and contributed little to canopy photosynthesis. But because high leaf efficiency did not compensate for the small leaf area, canopy photosynthesis decreased markedly as grazing intensity increased. Twice …

Value Of White Sweet Lupin In Production Of Protein Fodder And Feeding Of Animals, O Saric, I Ramosevac

IGC Proceedings (1977-2023)

The potential of white sweet lupin (Lupinus albus L.) as a grain or forage feed for livestock was investigated in a series of ex­periments. Grain yield of lupin was greater than or equal to that of soybeans (Glycine max [L.] Merrill) in most evaluations. The quality of lupin seed compared favorably with that of soybean meal and fishmeal. Lupin is capable of producing large amounts of forage in a short period, making it a good prospect for forage production in regions that have a short growing season.

A Case Study Of Suspected Sheep Losses Due To Chokecherry Not Death Camas, Kevin D. Welch, Clint A. Stonecipher, Stephen T. Lee, Daniel Cook, Benedict T. Green

Poisonous Plant Research (PPR)

Death camas (Zigadenus paniculatus) is a toxic plant often associated with poisoning cases in livestock, especially in sheep, in the spring on mountain foothills. Consequently, when sheep are found dead in mountain foothills, and death camas is present, it is often implicated as the potential cause of death. However, this may be over simplistic as there may be other plants that may also contribute to, or are the cause of, death in sheep. In this study, we present a case of approximately 200 sheep out of a band of 400 that died within 24 hours of beginning to …

Feeding Values Of Alfalfa And Its Dried Press Cake, R Kayama, H Tano, T Nagatomo, I Tasaki

IGC Proceedings (1977-2023)

In order to utilize forage crops effectively, extraction of leaf protein is quite useful, and its utilization has been extensively investigated. When leaf protein is extracted from plants, tremendous amounts of press cake are produced, however, only a few works on its utilization has been conducted. In the present experiment, the digestion trial with sheep was conducted and the feeding value of dried alfalfa press cake was compared with that of sun-cured alfalfa hay. In general, content of dry matter and organic matter was not so much.different between the press cake and the hay, however, the press cake was comparatively …

Seed, Seedling And Species Dynamics Of Grazed Annual Pastures In South Australia, E D. Carter, A Lake

IGC Proceedings (1977-2023)

The self-regenerating annual legumes mainly the medics (Medicago spp.) and subterranean clover (Trifolium spp.) are vital for maintaining the nitrogen economy of some 40 million hectares of crop and pasture land in Australia. However, new pests and diseases and poor management practices have caused serious decline of these annual legumes in many districts. In recent years a research program to identify the main factors causing legume decline has been started at the Waite Agricultural Research Institute. This research involves (i) studies of seed-seedling dynamics of the annual species of medics in the cereal-livestock zone (350-500mm annual rainfall) where legumes· are …

Comparison Of Nitrogen Utilization From Wilted And Direct-Cut Silages By Growing Sheep, Elisabeth Grenet, C Demarquilly, C Beranger, D Micol

IGC Proceedings (1977-2023)

The influence of wilting on the conservation quality, intake, digestibility and nitrogen balance of silages was studied. 32 silages made from 10 fresh crops were fed to growing sheep. For each crop a direct-cut silage without additive, a direct-cut silage with formic acid and a wilted silage were prepared. Conservation of wilted silages was not as good as that of direct-cut silages with formic acid but was better than that of silages without additive. However, both intake and protein digestibility of wilted silages were the lowest of the three types. The nitrogen balance was also lower with wilted silages than …

Composition And Nutritive Value Of Diets Selected By Sheep And Goats On Four Pasture Types, E C. Prigge, D B. Mpiri, W B. Bryan

IGC Proceedings (1977-2023)

Esophageally fistulated sheep (Ovis aries) and goats (Capra hircus) were compared in relation to the composition and nutritive value of ingesta collected by grazing four pasture types. The pasture types are described as Improved Pasture, Unimproved Pasture, Unimproved Pasture with Low Scrub and High Scrub. The scrub consisted mainly of hawthorne (Crataegus sp.) and blackberry (Rubus sp.). Samples of herbage and esophageal extrusa were visually separated into four forage classes (legumes, grass, forbs/browse and dead material). A significant (P < .01) animal species x type of pasture interaction was evident in regard to the preference for the various forage classes. The goats consumed much larger proportions of browse than the sheep on the pastures containing scrub. Few differences were evident between goats and sheep in nutritive value of the ingesta within pasture type.

The Cultivation And Feeding Value Of Persian Clover, P C. Flinn, K.F M. Reed, G R. Saul, G N. Ward, J G. Graham

IGC Proceedings (1977-2023)

Research with Persian clover (Trifolium resupinatum, ssp. majus) cv. Mara!, in south eastern Australia shows it to be productive and well adapted to waterlogged soils. It is particularly productive in spring when compared with other clovers. Winter production can be increased by sowing Persian clover with Westerwolds ryegrass or oats but the yield of clover in the spring is therby reduced. Persian clover conserved as hay was found to have a low neutral detergent fibre content (28.1 % ). In a 60 day feeding trial, lambs were fed Persian clover hay (78.5% digestible dry matter), lucerne hay (63.0% …

Effect Of Grazing On Pasture Production In South-West Western Australia, K.M S. Curtis, A C. Dunlop, T O. Albertson

IGC Proceedings (1977-2023)

INTRODUCTION With a mediterranean climate in the south-west of Western Australia, pastures are composed of annual species from the genera Trifolium, Hordeum, Lolium, Bromus, Vulpia, Erodium and Artotheca. The length of the growing season ranges from 9 months near the coast to less than 5 months in the eastern wheatbelt. Seven million hectares of pastures are grazed predominantly by Merino sheep (about 33 millions). Stoking rate is the major factor affecting wool production on farm. An increase in stocking rate reduces wool production per sheep.Increasing the stocking rate reduces total pasture growth (Dunlop, et al., 1984) and changes the botanic …

Mixed Animal Species Grazing Under Temperate And Semi-Arid Conditions, T Nolan, J Connolly, L M. Guillon, C Sall, K Dieye, K Dieye, H Guerin

IGC Proceedings (1977-2023)

Mixed grazing has been practiced for a long time, under a variety of climatic conditions, combinations of animal species and grazing managements (Nolan and Connolly, 1977). They suggested that although mixed grazing research progress was impeded by difficulties associated with the increased number of variables involved it offered greater opportunity to improve resource use. The purpose of this paper is to present results from recent research carried out under temperate and semi-arid conditions related to individual animal and per unit area outputs, animal/vegetation relationships and complemetary patterns of grazing behavious in relation to more efficient and balanced use of vegetation …

Effect Of Combining Hay Cube On The Digestibility Of Whole Crop Paddy Rice Haylage At The Ripe Stage, L F. Quinitio, K Taji

IGC Proceedings (1977-2023)

The study of paddy rice (PR) as feedstuff started at the National Agricultural Experiment Station in 1962. The original subject of the study was the utilization method of green PR by soiling as roughage. Subsequently, many results in the feeding value of PR soiling, hay, silage and grain have been reported by many workers. The structure of PR, as it results from the plants' growth and development, determines the foliage and grain parts, the former is roughage and latter is concentrate. In a series of PR utilization trials as feedstuff, the present study was conducted to investigate the effect of …

The Role Of Goats In New Zealand Hill Country Farming, D A. Clark, M G. Lambert

IGC Proceedings (1977-2023)

The predominant domesticated ruminants in New Zealand are sheep and cattle. However in the last decade other animal species have been incorporated into farming systems, particu­larly goats which have increased from 10 thousand to 1 million over that time. The motives for this change have primarily been economic ones, in an attempt by farmers to increase income and reduce costs. Goats provide direct financial returns to hill farmers through sale of fibre (mohair, cashgora, cashmere) and meat. In many instances however, the motivation has been one of reduction of weed control costs. Aspects of weed control, pasture response and grazing …

Effect Of Repeated Applications Of Fluidized Bed Combustion Residue To Reclaimed Surface Mined Pastures, M A. Cochran, J P. Fontenot, H D. Perry, V G. Allen

IGC Proceedings (1977-2023)

Reclaimed surface mined land is potentially valuable for use as pasture, but its low fertility limits its use without soil amend­ment (Armiger et al., 1976). The usual acidic nature of these soils may result in mineral deficiencies and toxicities in forage (Vogel, 1981). Fluidized bed combustion residue (FBCR) is the residue from combustion of coal with limestone mixed in a jet air stream in coal-burning power plants (Fennelly, 1984). The procedure is used to trap pollutants such as sulfur dioxide, nitrogen oxides, and volatile elements that would normally be emitted into the atmosphere. The FBCR retains about 50 % of …

Synthese De La Recherche Sur Les Especes Annuelles De Medicago En Elgerie, L Adem

IGC Proceedings (1977-2023)

En Algerie, ii existe pratiquement une dichotomie entre la cerealiculture dans la zone Nord (300 a 500 mm de pluie) et l'elevage ovin relegue en zone steppique (250 mm de pluie). Le cheptel ovin ne peut survivre uniquement sur !es maigres res­sources de la steppe; !es apports de fourrages secs et !es migra­tions estivales vers le Nord restent necessaires. Pour !'integration cerealiculture-elevage, la creation des piiturages annuels de Medicago au depens des jacheres impro­ductives (mains de 250 UF/ha) etait imperative et a debute des octobre 1972. Ces piiturages ameliores contribueraient a reduire un deficit de 3 milliards d'UF sur un …

Productivity And Nutritive Value Of Coastal And Valley Bottom Plant Communities In The Falkland Islands, J A. Kerr, J H. Mcadam

IGC Proceedings (1977-2023)

In the Falkland Islands, short dense grassland communities ("greens") in valley-bottoms, and in coastal areas often associated with dense populations of seabirds, are selectively grazed by livestock and wild geese within the extensive grazing systems. Annual and seasonal herbage productivity, botanical composition, digestibility and utilisation, of greens were experimentally assessed at 6 sites on Bast Falkland. Herbage productivity, digestibility and utilisation were higher than reported for the dominant Cortaderia communities and compared favourably with Improved pastures. Botanical composition of green types were similar. Despite their uneven distribution and low area, greens are an important forage resource and could be used …

Digestion And Rumen Metabolism Of Forages By Red Deer, Goats And Sheep, T N. Barry, B M.F Dominngue, D O. Freudenberger

IGC Proceedings (1977-2023)

Digestive efficiency was compared in Red deer, goats and sheep fed chaffed lucerne hay (Experiment 1), Goats digested fibre more efficiently than sheep and had the greatest rate of rumen ammonia production, Red deer showed the capacity to increase VFI from winter (W) to summer (S) without depressing apparent digestibility, through slowing the rate of rumen particulate outflow. Fractional outflow rate (FOR) of water from the rumen and the ratio FOR water/ FOR particulate matter were both considerably greater for deer than for sheep and goats. It was concluded that this would enable deer to digest soluble ration components more …

Behavior Of Goats And Sheep On An Eroded Hill Country Pasture In Winter, L A. Greaves, M E. Wedderburn

IGC Proceedings (1977-2023)

The behaviour of cashmere-producing does was compared with that of Romney ewes on an area of surface erosion in pasture-dominated hill country during winter. Five ewes and 5 does were monitored. Each group was observed for 4 days, during June-July, from dawn to dusk. A fixed, remote video camera was used to record the animals' behaviour. Tapes were later analysed, noting animal activity, position and time. Bwes spent 13% of their day on the eroded surfaces compared to 2% for the does, Does were observed on the erosion mainly in the afternoon, whereas the ewes were present at all stages …

A Slow Release Intra-Ruminal Device For Protection Against Facial Eczema In Sheep, R Munday, E A. Fowke, A M. Thompson, C Wesselink, N R. Towers

IGC Proceedings (1977-2023)

Facial eczema (FE) is a hepatogenous photosensitization disease of ruminants which causes severe losses in agricultural revenue in New Zealand. It is caused by sprophytic, a myotoxin produced by the saprophytic pastoral fungus Pilllomyces chartarum. Zinc (Zn) salts, given to animals before exposure to the toxin, protect against the harmful effects of sporidesmin. Large amounts of Zn are required and dosing must be continued, at regular intervals, throughout the period when animals are exposed to the fungus. While practicable for dairy cattle, these requirements preclude the routine use of Zn for FB prophylaxis in sheep. For these animals, a …

System Research: Preliminary Results From A Farmlet Comparison Between A Biological And Conventional Sheep And Beef System, A D. Mackay, D I. Gray, I M. Brookes, P J. Budding, B Devantier

IGC Proceedings (1977-2023)

Initial findings of a farm let study comparing biological (agrochemical­ free) and conventional sheep and beef production are presented and discussed. Little difference was found in sheep production between the two systems in 1991-92, despite large differences in the level of internal parasitism, particularly in young sheep. In contrast! growth rates of rising 1 year steers and heifers on the conventional unit were superior to those of the biological farmlet throughout spring and summer of the first year. While a reduction in the use of anthelmintic drench would have little impact on the productivity of sheep systems, the productivity of …

Intake Of South African Mutton Merino Ewes On Wheat Stubble Grazing, T S. Brand, J M. Van Heerden, F Franck

IGC Proceedings (1977-2023)

Wheat stubble was grazed continuously for 154 days during the summer (December-April) by reproducing and dry ewes (n-8) at 2 stocking rates ( 1 or 2 ewes/ha), Samples were collected for chemical analysis from oesophageally fistulated (OF) sheep. Intake was determined using controlled chromium-release devices. The mean CP, ADF and NDF contents and iii vitro OM digestibility of samples were respectively 16.1:t0.4%; 40.7:t0.8%, 59.0:tl.1% and 48.5±0.7% t 1 ewe/ha and 10.8±1.1%; 53.9±1.1%, 72.1±0.9% and 48.8:t0.7% at 2 ewes/ha. The mean CP intake of dry ewes was 202±7 g/day (I ewe/ha) and 113:t6 g/day (2 ewes/ha), while the CP intake of …

Effect Of Percentages Calluna Vulgaris Cover And Cow And Ewe Physiological Status On Animal Production On Mountain Pastures, K Osoro, R Celaya, Mamen Olivan

IGC Proceedings (1977-2023)

The effect percentage cover of Calluna vulgaris (30 or 70%) on performance of dry and lactating ewes and cows with their lambs and calves was studied during 1990 and 1991. Lactating cows had greater body weight losses than dry ones, the difference being 0.3 and 0.S kg/day for 1990 and 1991 respectively. Percentage C.vulgaris cover (30 or 70%) caused differences in body-weight losses· similar to those caused by physiological status. Milk production from the cows, and therefore calf live-weight gain, were significantly higher in the group grazing on the plot with 30% Calluna (0.62 and 0.71 kg/day for 1990 …

Integrated Grazing Of Goats With Sheep Or Cattle On Continuously Grazed Pasture, A M. Nicol, A.J F. Russel, I A. Wright

IGC Proceedings (1977-2023)

Oroups of ewes (10) and their twin lambs were grazed on sown ryegrass• white clover (Lolium perenne L.-Trifollum repens L.) pastures maintained at a sward surface height of 4 or 8 cm and a further group grazed with yearling goats (in a proportion of 1/3 ewe plus lamb live weight) also at fi cm. A second concurrent experiment consisted of 3 similar treatments using young cattle with sward surface heights of 8 and 12 cm. Results over the 140-day grazing period showed that allhough the diet selected by sheep and cattle grazed with goats contained more green grass …