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Articles 6151 - 6180 of 59532

Full-Text Articles in Earth Sciences

Historical Structural Analysis Of The Rileyville Quadrangle, Page County, Virginia, Sydney Fergen Jul 2024

Historical Structural Analysis Of The Rileyville Quadrangle, Page County, Virginia, Sydney Fergen

2024 Symposium

The Northwest corner of Virginia, within the Appalachian Mountains, formed during a collision of continents called the Alleghenian Orogeny roughly 250 million years ago(Ma). This event caused tectonic plates to collide, reforming the fractured continental crust back into a new supercontinent, Pangaea. This process took over 100 Ma and closed the Rheic Ocean. These large-scale compressional tectonics had several effects including formation of the Allegheny Plateau and Taconic Mountain range, which has gradually eroded exposing a series of plunging folds and imbricated thrust faults. This poster presents a structural analysis of the Rileyville quadrangle to help decipher regional geologic history …


U/Pb Zircon Ages Of Saltese Upland Conservation Area, Priest River Core Complex, Jessica M. Lawrence, Natalie Potter, Chad Pritchard Jul 2024

U/Pb Zircon Ages Of Saltese Upland Conservation Area, Priest River Core Complex, Jessica M. Lawrence, Natalie Potter, Chad Pritchard

2024 Symposium

The Saltese Upland Conservation Area provides a window into the Priest River Core Complex with Lake Hauser gneiss grading to migmatite, garnet-baring amphibolite juxtaposed with felsite to orthogneiss rocks. U/Pb ages from LA-ICP-MS of separated zircon grains show trends very similar to detrital 207Pb/206Pb ages of the Belt Supergroup. The amphibolite displays a much stronger peak at 1.4 to 1.5 Ga , possibly related to the emplacement of Mesoproterozoic dikes. The amphibolite and granitic rocks also contain a number of grains with 238U/206Pb around 60 Ma preserving events from the uplift of the Priest River Complex in the Spokane area. …


Paleohydraulic Analysis Of Megaripples From Outburst Floods In Omak, Washington, Jessica M. Lawrence Jul 2024

Paleohydraulic Analysis Of Megaripples From Outburst Floods In Omak, Washington, Jessica M. Lawrence

2024 Symposium

Located in Omak, Washington atop what is observed to be a gravel point bar are giant current ripples associated with outburst floods that took place during the Pleistocene (O’Connor et al. 2020 and Minard 1985). Thorough breakdown of these giant current ripples was conducted using their geomorphologies associated with stream flow mechanisms for gravel bedforms such as hydraulic radius of cross- sectional area and velocity using Manning’s equation to determine Froude’s Number (USDA 2007). Ripple index associated with ripple wavelength and height was then compared to additional megaripples located throughout Scablands of Washington that have been correlated to the Great …


Geotechnical Analysis Of Soil Sample Pp-7 From The Ewu Palouse Prairie Restoration Site, Cheney, Wa, Jessica M. Lawrence, Sydney Fergen, Kai L. Valentine, Annika Smith Jul 2024

Geotechnical Analysis Of Soil Sample Pp-7 From The Ewu Palouse Prairie Restoration Site, Cheney, Wa, Jessica M. Lawrence, Sydney Fergen, Kai L. Valentine, Annika Smith

2024 Symposium

The Eastern Washington University Palouse Prairie Restoration Project is a program set to restore 120 acres of Palouse prairie back to its native habitat. The land is currently leased as a no till annual wheat field. The soil lies atop Pleistocene loess from the Cordilleran Ice Sheet and glaciofluvial deposits from the Great Missoula Floods. There were 9 different soil samples collected from the Palouse prairie restoration project area. Group 7 analyzed soil sample PP-7 collected at 47.492747°N, -117.593442°W, on September 21st, 2023, and over 10 weeks, tested the specific gravity (ASTM D854), particle size distribution (ASTM D422, D7928), soil …


A Seasonal Decomposition Comparison Between Forest And Turf Habitats: Implications For Climate Change, Amanda Shirmer Jul 2024

A Seasonal Decomposition Comparison Between Forest And Turf Habitats: Implications For Climate Change, Amanda Shirmer

DePaul Discoveries

Decomposition is an essential ecosystem service in which microorganisms breakdown organic matter. This process improves soil health and acts as a vital step in global carbon cycles. In this study, we examined decomposition rates and associated soil properties in turf and forest habitats across summer and fall seasons in order to determine how land management practices and climate change may be altering local decomposition regimes. Our study determined that there was a statistically significant difference between decomposition rates in turf and forest ecosystems (P=0.003) and a significant difference in decomposition rate across season (P


Gnss And Insar Observations Of Vertical Motion In The Valles Caldera, Nm, Savannah Chase Devine Jul 2024

Gnss And Insar Observations Of Vertical Motion In The Valles Caldera, Nm, Savannah Chase Devine

Earth and Planetary Sciences ETDs

The Valles caldera is a rhyolitic “supervolcano” formed 1.231 Ma. An understanding of whether Valles caldera is currently deforming is needed to inform volcanic hazard estimates for northern New Mexico and will allow for a better understanding of the hazards presented by other rhyolitic caldera systems. Here, we present an InSAR time series of the Valles Caldera using 37 interferograms, spanning 2014 to 2022, which show a small but consistent signal of broad pattern subsidence/yr. We also present GNSS observations from a survey conducted in October 2022 and compare the results to surveys in 2002 and 2003 to estimate the …


Data Requirements For Whole-Farm Economic Analysis Of Grazing Alternatives, R O. Burton Jr Jul 2024

Data Requirements For Whole-Farm Economic Analysis Of Grazing Alternatives, R O. Burton Jr

IGC Proceedings (1977-2023)

The purpose of this paper is to contribute to better communications among the agronomists, animal scientists, and agricultural economists on interdisciplinary teams, that wish to provide useful information to forage producers. This is accomplished by discussing major issues and data requirements for whole-farm economic analysis.


Native Grasslands Of Yugoslavia As A Potential For "Biologically High Quality Food" Production - To Be Preserved And Used For The Benefit Of All, Djordjevic-Milosevic Suzana, Negovanovic Dragan, Zakonovic Miodrag Jul 2024

Native Grasslands Of Yugoslavia As A Potential For "Biologically High Quality Food" Production - To Be Preserved And Used For The Benefit Of All, Djordjevic-Milosevic Suzana, Negovanovic Dragan, Zakonovic Miodrag

IGC Proceedings (1977-2023)

Natural grasslands are the base of the livestock production in the hilly-mountainous regions of Yugoslavia. Poor economic power of the owners of these areas brought about a complete dying out of agricultural production in these regions in the last few years. In the same time, the lack of financial resources made it impossible for the farmers to use the fertilisers, protective and other chemical agents which result in a high degree of environmental preservation. Due to current economic policy at this time the population has moved out and there is no industrialisation. The revival of agriculture on the hilly-mountainous regions …


Some Economics Problems Of Range Resource Analysis In Free And Open Access Environment, E Tedonkeng Pamo Jul 2024

Some Economics Problems Of Range Resource Analysis In Free And Open Access Environment, E Tedonkeng Pamo

IGC Proceedings (1977-2023)

Economic analysis has been the traditional means by which the costs and benefits of rangeland conservation and sustained development have been identified. Conventional analysis has proved inadequate for dealing with the following realities : (1) open access in circumstances of poorly defined common-resource ownership tends to encourage over exploitation; (2) many costs of rangeland degradation involve externalities that will occur in the future; (3) the values of preservation and sustained management are substantial and can be translated into financial assistance; and (4) benefits from rangeland are not often appreciated because of lack of knowledge from rangeland. Recent approaches to economic …


Studies On The Distribution And Formation Of The Meadows In China, Feng Guojun, Zhang Xiujun, Zhu Libuo, Wei Shaocheng, Zhang Yongliang Jul 2024

Studies On The Distribution And Formation Of The Meadows In China, Feng Guojun, Zhang Xiujun, Zhu Libuo, Wei Shaocheng, Zhang Yongliang

IGC Proceedings (1977-2023)

The lowland meadows are distributed on the Northeast Plains in the temperate zone in China, and its area became less and less with an increase of longitude. There are some regularities for the distribution of montane meadows, sub-montane meadows and cold-alpinal meadows. And the distribution and formation for meadows are independent upon the zonal climate and their environmental soil moisture.


Sward Structure Under Continuous And Rotation Grazing, V Pavlu, J Velich Jul 2024

Sward Structure Under Continuous And Rotation Grazing, V Pavlu, J Velich

IGC Proceedings (1977-2023)

Sward structure under continuous (CG) and rotational (RG) grazing system was studied at an experimental pasture in the Jizerské hory mountains. Herbage mass and vertical distribution was assessed by cutting ten quadrats (0.1 x 0.5 m) and separated into grass, white clover, dandelion, other forbs and dead material. The proportions of grasses was higher at RG (on average 51% of the pasture mass) than at CG (41%). In the years with normal amount and distribution of precipitation the proportion of white clover was higher at CG (17%) than at RG (9%). The lack of summer precipitation damaged more significantly the …


Beef Cattle Production On Renovated Grass Pastures In Savannas Of Brazil, V.P B. Euclides, M.C M. Macedo, M P. Oliveira Jul 2024

Beef Cattle Production On Renovated Grass Pastures In Savannas Of Brazil, V.P B. Euclides, M.C M. Macedo, M P. Oliveira

IGC Proceedings (1977-2023)

A 3-year grazing trial was conducted, to study animal production on degraded grass pastures, renovated by two levels of fertilization. All paddocks were divided into halves: one received 1.5 t/ha of dolomitic limestone, 400 kg/ha of a fertilizer formula 0-16-18 and 50 kg/ha of microelements (FL1); and the other 3.0 t/ha , 800 kg/ha and 50 kg/ ha of the same fertilizers (FL2). Productivity on FL2 pastures was greater than that on FL1 pastures, averaging 565 and 395 kg of liveweight gain (LWG)/ha/year, respectively. For all grasses the productivity in both fertilizer treatments decreased linearly from the first to the …


Pasture Attributes And Live-Weight Gain Of Lambs Grazing With Different Supplementation Levels, P A. Martinez-Hernandez, M Meza-Nieto, J Perez-Perez, R Barcena, J G. Herrera Jul 2024

Pasture Attributes And Live-Weight Gain Of Lambs Grazing With Different Supplementation Levels, P A. Martinez-Hernandez, M Meza-Nieto, J Perez-Perez, R Barcena, J G. Herrera

IGC Proceedings (1977-2023)

The purpose of this study was to determine pasture attributes, liveweight gain and stocking rate from a mixed pasture grazed by lambs recieving different supplementation levels. There were four treatments: in two, lambs grazed at 4 or 8% herbage allowance, no supplement; in the other two, lambs grazed at 4% herbage allowance plus a concentrate to cover 25 and 30 or 50 and 60% of estimated daily needs of metabolizable energy and crude protein. Pasture was of perennial and annual ryegrass, orchard grass and red clover. Pre and postgrazing forage mass, crude protein and dead material were not different (P …


Characteristics Of Grass Species In Pasture For High Producing Cows In Northern Japan, K Sudo, K Ochiai, T Ikeda Jul 2024

Characteristics Of Grass Species In Pasture For High Producing Cows In Northern Japan, K Sudo, K Ochiai, T Ikeda

IGC Proceedings (1977-2023)

The prupose of this research was to investigate characteristics of grass species under different conditions appropriate to the intensive grazing system for high producing cows (8000 kg for a 305-day lactation) in northern Japan. Meadow fescue (Festuca elatior L.), timothy (Phleum pratense L.) and perennial ryegrass (Lolium perene L.) white clover (Trifolium repens L.) pastures were established and divided into two plots by difference of regulated plant height (meadow fescue and timothy) or of stocking intensity (perennial ryegrass). Each plot was 60m2 and was grazed when plant height reached 20cm or 30cm. Meadow fescue and perennial …


Agenda De Investigación Para El Manejo Sustentable Del Manglar En Tamaulipas, México [Research Agenda For The Sustainable Management Of Mangroves In Tamaulipas, Mexico], Carlos Zamora-Tovar, Alejandro Fierro-Cabo, Glenda Nelly Requena-Lara Jul 2024

Agenda De Investigación Para El Manejo Sustentable Del Manglar En Tamaulipas, México [Research Agenda For The Sustainable Management Of Mangroves In Tamaulipas, Mexico], Carlos Zamora-Tovar, Alejandro Fierro-Cabo, Glenda Nelly Requena-Lara

School of Earth, Environmental, & Marine Sciences Faculty Publications

Se presenta un análisis de la información ecológica disponible sobre los manglares de Tamaulipas, México. El objetivo fue establecer una línea base de conocimiento que defina el estado del arte a partir de la información publicada; actualizar la estructura forestal con datos propios observados en el año 2018; y determinar una agenda de investigación prioritaria para el manejo sostenible del ecosistema de man-glar, ecosistema de vital importancia por la gran variedad de recursos y servicios ambientales que aporta a la sociedad. La investigación bibliográfica recopiló 32 trabajos relevantes: 16 publicaciones formales, siete ediciones institucionales y nueve consideradas literaturas gris; recopilación …


Preliminary Analysis Of Per-And Polyfluoroalkyl Substances (Pfas) In Surface Waters Of The West Plains Region Of Spokane County, Jerusha Hampson Jul 2024

Preliminary Analysis Of Per-And Polyfluoroalkyl Substances (Pfas) In Surface Waters Of The West Plains Region Of Spokane County, Jerusha Hampson

2024 Symposium

Per-and Polyfluoroalkyl Substances (PFAS) have become a national issue as regulatory limits for these toxins have just recently been put into the Clean Water Act. The West Plains has been significantly impacted by PFAS contamination due to the decades-long use of aqueous film-forming foam (AFFF) for firefighting training at both Fairchild Airforce Base and the Spokane International Airport. Though research is still underway, it is known that PFAS contamination in West Plains groundwater is significant and widespread. This study focuses on West Plains surface waters, as there is currently less information about how these water bodies are impacted by PFAS. …


Live-Weight Gain Of Steers Grazing African Star Grass Four Herbage Allowances, J Perez-Perez, J O. Hernandez-Velez, J G. Herrera-Haro, R Barcena-Gama Jul 2024

Live-Weight Gain Of Steers Grazing African Star Grass Four Herbage Allowances, J Perez-Perez, J O. Hernandez-Velez, J G. Herrera-Haro, R Barcena-Gama

IGC Proceedings (1977-2023)

The objective was to determine weight changes of steers grazing African star grass (Cynodon plectostachyus) at four herbage allowances (2.0, 2.5, 3.0 and 3.5 kg of dry matter/100 kg of live weight day-1). A rotational grazing system with 10 grazing days and 30 days rest was followed. A Split Plot Design with four replications was used. Response variables were: daily gain per steer (DGS) and per hectare (DGH), dry matter forage yield (FY), % of utilization (% U) and in vitro dry matter digestibility (DMIVD). DGS and DGH were not different (P >0.05) among allowances and grazing periods. …


Strategic Use Of Brachiaria Decumbens Pasture To Beef Heifers During Dry Season, E G. Cardoso, N F. Seiffert, J Marques Da Silva, V.P. B. Euclides, J M. Vieira Jul 2024

Strategic Use Of Brachiaria Decumbens Pasture To Beef Heifers During Dry Season, E G. Cardoso, N F. Seiffert, J Marques Da Silva, V.P. B. Euclides, J M. Vieira

IGC Proceedings (1977-2023)

The main objective of this study was to evaluate a Brachiaria decumbens pasture, instead of a common rangeland, for zebu beef heifers during the dry season of the year as a means of anticipating the first calving age from four to three years of age, and so improve the production rate of the herd. Daily liveweight gains (DLWG) were analyzed for the effects of year and three stocking rates during the dry season (SR1=1.5; SR2=2.0 and SR3=2.5 head/ha). The main effect on heifers DLWG was the year (P<0.01), but SR was also important (P<0.05), mainly during the last half of the dry season when pastures are under severe constraints such as soil moisture deficit and low temperatures. The lowest SR presented the highest DLWG (0.204a, 0.174ab and 0.145b kg/head, respectively for SR1, SR2 and SR3), during the dry season. If climatic conditions are not exceptionally bad, heifer first calving occurs at 37 months of age when reared on B. decumbens.


Quality Grassland For Dairy Production In North-West Spain, A Gonzalez-Rodriguez Jul 2024

Quality Grassland For Dairy Production In North-West Spain, A Gonzalez-Rodriguez

IGC Proceedings (1977-2023)

An experiment with two groups of 15 Friesian cows grazing independent areas, with no N and 240 kg N ha-1, was run during two years to see the levels of milk production based on a grass/white clover pasture, maintaining high levels of herbage quality. N application decrease clover content from 55% to 42%. The total DM response to N was low. Herbage utilization was maintained similar in both treatments. Moderate levels of milk production can be reached, more than 4000 litres cow-1 and 9000 litres ha-1, with low use of concentrates, only 400 kg cow-1. Crude protein levels were high …


Sward Height On The Performance Of Cow-Calf Units And Yearling Steers Grazing Cool Season Pasture, E C. Prigge, W B. Bryan, E L. Nestor Jul 2024

Sward Height On The Performance Of Cow-Calf Units And Yearling Steers Grazing Cool Season Pasture, E C. Prigge, W B. Bryan, E L. Nestor

IGC Proceedings (1977-2023)

Performance and grazing time of cow-calf units and yearling steers were determined over four years on naturalized cool season pastures maintained at a sward height of 4-6, 6-8, 8-10, or 10-12 cm. Daily gains of cows and steers responded quadratically (P<0.05) to increasing sward heights, with gains maximized at 8-10 cm. Milk production of the cows and gain of the calves were not affected (P>0.10) by sward height. Grazing days (cow-calf unit/hectare) decreased linearly (P<0.01) with increasing sward height. The proportion of the day spent grazing for cows and steers decreased in a linear manner (P<0.05) as pasture height increased. Cows spent less time grazing than steers (P<0.05) at all but the low pasture height.


Buffer Grazing For A Twelve Month Cow-Calf Production System, W B. Bryan, E C. Prigge, D J. Flaherty, G E. D'Souza Jul 2024

Buffer Grazing For A Twelve Month Cow-Calf Production System, W B. Bryan, E C. Prigge, D J. Flaherty, G E. D'Souza

IGC Proceedings (1977-2023)

Set stocking is a widely used grazing management for beef cow-calf production on Appalachian hill land pastures of the USA. A replicated study was conducted to compare a conventional (set stocking) and buffer grazing management. For the buffer system, grazing area was restricted in the spring and hay was harvested from the ungrazed area. In summer, a portion of this area (buffer) was grazed and a second cutting of hay removed from the remaining area. For the conventional treatment a fixed area was set stocked and hay was harvested on an area designated for hay only. Land areas and fertilizer …


Intensive Rotational Grazing Systems For Dairying In A Subtropical Environment: Animal, Plant, And Soil Responses, J H. Fike, C R. Staples, L E. Sollenberger, D A. Graetz Jul 2024

Intensive Rotational Grazing Systems For Dairying In A Subtropical Environment: Animal, Plant, And Soil Responses, J H. Fike, C R. Staples, L E. Sollenberger, D A. Graetz

IGC Proceedings (1977-2023)

Forage species, stocking rate, and supplementation rate effects upon performance of lactating dairy cows were studied. Forage mass and nutritive value and nutrient concentration in shallow groundwater also were measured. Cows (n = 44) grazed bermudagrass (Cynodon dactylon) or rhizoma peanut (Arachis glabrata), stocked at 4.9 or 7.4 cows ha-1, and 2.5 or 4.9 cows ha-1, respectively. Pelleted concentrate:whole cottonseed (80:20) was offered twice daily post milking at 1 kg per 2 or 3 kg of daily milk production. Cows grazing rhizoma peanut produced more (P = .076) milk per day but had greater (P = …


High Moisture Corn Supplementation Of Different Dry Matter Content To Cows Grazing Temperate Pasture, D H. Rearte, H Alvarez, F Santini Jul 2024

High Moisture Corn Supplementation Of Different Dry Matter Content To Cows Grazing Temperate Pasture, D H. Rearte, H Alvarez, F Santini

IGC Proceedings (1977-2023)

The objective of this study was to evaluate grazing dairy cows performance supplemented with high moisture corn of different dry matter content. Cows grazed fresh forage oat day and night and received 5 kg DM high moisture corn daily. Treatments 1 and 2 were high moisture corn of 30% and 18% moisture content respectively. Twenty Holstein cows were used for milk production and composition studies and six rumen fistulated cows were used for rumen digestion studies. Milk production and composition and body weight gain were not affected by the dry matter content of the supplemented high moisture corn. Related to …


Intake Of High Producing Holstein Cows Grazing Pasture Or Fed A Total Mixed Ration, E S. Kolver, L D. Muller Jul 2024

Intake Of High Producing Holstein Cows Grazing Pasture Or Fed A Total Mixed Ration, E S. Kolver, L D. Muller

IGC Proceedings (1977-2023)

The ability of a pasture diet to support a high dry matter intake without supplementary feed was determined using 16 high producing Holstein cows. Cows (n=8) were adapted to an all-pasture diet by incrementally reducing the amount of total mixed ration (TMR) fed over four weeks. A control group of cows (n=8) remained in confinement and were fed a TMR. Performance of grazing cows differed significantly (P < 0.001) from TMR fed cows by intake (19.0 vs. 23.4 kg DM/d), milk production (29.6 vs. 44.1 kg/d), milk protein content (2.61 vs. 2.80%), liveweight (562.1 vs. 597.3 kg), and condition score (2.02 vs. 2.50). Results indicate that intake of good quality pasture is higher than previously estimated for high producing Holstein cows in the USA, but that milk production is 15 kg/d less than when cows are fed a TMR.


Cattle Production And Botanical Composition In Continuously Stocked Grass-Clover Swards, A Elgersma, H Schlepers Jul 2024

Cattle Production And Botanical Composition In Continuously Stocked Grass-Clover Swards, A Elgersma, H Schlepers

IGC Proceedings (1977-2023)

The performance of grass-clover mixtures was evaluated under cattle grazing, and the relations between grass variety, clover content and animal production were studied during four years at three locations. The prostrate diploid perennial ryegrass variety formed a dense sward with less clover and less weeds than the tetraploid or the erect diploid ryegrass varieties, which contained about the same amount of clover in the mixture. The ryegrass tiller density was lowest in the tetraploid. These differences between mixtures were not reflected in differences in animal performance or net energy production.


Production Efficiency Benchmarks For Irrigated Dairying In South Eastern Australia, K E. Pritchard, O A. Gyles, D P. Armstrong, S L. Spiteri Jul 2024

Production Efficiency Benchmarks For Irrigated Dairying In South Eastern Australia, K E. Pritchard, O A. Gyles, D P. Armstrong, S L. Spiteri

IGC Proceedings (1977-2023)

Milk production from grazed irrigated pasture is an important industry in south eastern Australia. Irrigation water is essential for perennial pastures, but the efficiency with which the irrigation water is used to produce milk varies widely between farms. As irrigation water is a limiting resource, future productivity increases will depend on increasing the amount of milk produced per unit of water applied. This research project estimates metabolisable energy utilised from grazed pasture, using energy values for animal requirements, products and feedstuffs. Efficiency criteria, in terms of production per hectare of irrigated pasture, per megalitre of irrigation water, and per cow …


Grazing Management And Nitrogen Fertilizer Effects In Grazing Systems For Beef Cows, D G. Morrison, C C. Willis, D L. Castle, G J. Cuomo Jul 2024

Grazing Management And Nitrogen Fertilizer Effects In Grazing Systems For Beef Cows, D G. Morrison, C C. Willis, D L. Castle, G J. Cuomo

IGC Proceedings (1977-2023)

Four 8-ha areas, primarily Cynodon dactylon forage, were overseeded in autumn with annual ryegrass (Lolium multiflorum) and clover (Trifolium incarnatum and Trifolium repens). Two areas received no nitrogen (N) fertilizer and two received 168 kg N/ha annually. Within N level (2 x 2 factorial), one area was divided into 4 paddocks (pad) and the other into 16 pad for rotational grazing. Spring-calving beef cows were stocked (2.5/ha) year-round on each area with calves weaned in October. Annual dry matter forage accumulation was greater where N was applied (18.2 vs 14.2 Mg/ha, P=.02) but was unaffected by …


Sheep Production On An Annual And Perennial Pasture In Southwest Australia, P Sanford, J Gladman, L Cransberg Jul 2024

Sheep Production On An Annual And Perennial Pasture In Southwest Australia, P Sanford, J Gladman, L Cransberg

IGC Proceedings (1977-2023)

Sheep production on an annual and perennial pasture stocked at 11.5 dse/ha, was compared in a mediterranen environment at Manypeaks in Western Australia. The annual sward comprised of 48% subterranean clover (Trifolium subterraneum L.), 20 % annual grasses (Lolium rigidum Gaudin, Hordeum leporinum Link, Vulpia bromoides (L.) S.F. Gray) and 32% capeweed (Arctotheca calendula L.). The perennial sward was 19% kikuyu (Pennisetum clandestinum), 36% subterranean clover, 43% annual grasses (Lolium rigidum Gaudin, Hordeum leporinum Link, Vulpia bromoides (L.) S.F. Gray) and only 2% capeweed which was displaced by kikuyu. Both pasture types had similar growth …


Milk Production And Composition In Charolais And Polled Hereford Cows On Different Forage Systems, J M. Phillips, R B. Simpson, J D. Shockey, S C. Nickerson Jul 2024

Milk Production And Composition In Charolais And Polled Hereford Cows On Different Forage Systems, J M. Phillips, R B. Simpson, J D. Shockey, S C. Nickerson

IGC Proceedings (1977-2023)

The objective of this study was to study the effect of different winter and summer forage systems on milk production and composition in beef cows. Charolais and Polled Hereford cows were assigned to receive either grass hay and supplemental feed or ryegrass pasture during the late winter/early spring period, and then allowed to either graze warmseason grass pasture on a continuous or rotational basis during the summer period. Representative cows were machine-milked on day 48 (hay/feed vs ryegrass), on days 117 and 175 (continuous vs rotational grazing) postpartum. Milk weights were recorded and converted to 24- hour yields. Samples were …


Intensive Grazing Management For Dairy Heifers, J R. Rodgers Jul 2024

Intensive Grazing Management For Dairy Heifers, J R. Rodgers

IGC Proceedings (1977-2023)

After grazing our milking herd on intensive rotational grazing for three years utilizing many paddocks and different types and configurations of fencing to control the wise use of the grass and legume species already on our farm, we moved to develop our second farm into a commercial heifer growing project. This paper will attempt to share our practical experience through three years of grazing upwards of 400 Ayrshire and Holstein heifers from six months of age until just prior to calving. Our ultimate objective is year end financial solvency.