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Roly Poly And Its Management, Department Of Primary Industries And Regional Development, Western Australia
Roly Poly And Its Management, Department Of Primary Industries And Regional Development, Western Australia
Grains and other field crops factsheets
Roly poly, also known as prickly saltwort or tumbleweed (Salsola australis), is a native species found throughout Australia. The dead plants can break off at ground level, forming the ‘tumbleweeds’ seen in movies.
Like most summer weeds, roly poly uses soil moisture and nutrients that would otherwise be available to the following crop. The time taken to clear uncontrolled plants can delay seeding.
Livestock will graze the young plants; however, they will not eat the mature plants and are injured by the prickly leaves.
Nitrate Removal By Floating Treatment Wetlands Under Aerated And Unaerated Conditions: Field And Laboratory Results, Jenna Mccoy, Matt Chaffee, Aaron Mittelstet, Tiffany L. Messer, Steve Comfort
Nitrate Removal By Floating Treatment Wetlands Under Aerated And Unaerated Conditions: Field And Laboratory Results, Jenna Mccoy, Matt Chaffee, Aaron Mittelstet, Tiffany L. Messer, Steve Comfort
Earth and Environmental Sciences Faculty Publications
Urban and storm water retention ponds eventually become eutrophic after years of receiving runoff water. In 2020, a novel biological and chemical treatment was initiated to remove accumulated nutrients from an urban retention pond that had severe algae and weed growth. Our approach installed two 6.1 m × 6.1 m floating treatment wetlands (FTWs) and two airlift pumps that contained slow-release lanthanum composites, which facilitated phosphate precipitation. Four years of treatment (2020–2023) resulted in median nitrate-N concentrations decreasing from 23 μg L−1 in 2020 to 1.3 μg L−1 in 2023, while PO4-P decreased from 42 μg L−1 to 19 μg …
Planetary Health Learning Objectives: Foundational Knowledge For Global Health Education In An Era Of Climate Change, Kathryn H. Jacobsen, Caryl E. Waggett, Pamela Berenbaum, Brett R. Bayles, Gail L. Carlson, René English, Carlos A Faerron Guzmán, Meredith L. Gartin, Liz Grant, Thomas L. Henshaw, Lora L. Iannotti, Philip J. Landrigan, Nina Lansbury, Hao Li, Maureen Y. Lichtveld, Ketrell Mcwhorter, Jessica E. Rettig, Cecilia J. Sorensen, Eric J. Wetzel, Dawn Michele Whitehead, Peter J. Winch, Keith Martin
Planetary Health Learning Objectives: Foundational Knowledge For Global Health Education In An Era Of Climate Change, Kathryn H. Jacobsen, Caryl E. Waggett, Pamela Berenbaum, Brett R. Bayles, Gail L. Carlson, René English, Carlos A Faerron Guzmán, Meredith L. Gartin, Liz Grant, Thomas L. Henshaw, Lora L. Iannotti, Philip J. Landrigan, Nina Lansbury, Hao Li, Maureen Y. Lichtveld, Ketrell Mcwhorter, Jessica E. Rettig, Cecilia J. Sorensen, Eric J. Wetzel, Dawn Michele Whitehead, Peter J. Winch, Keith Martin
Earth and Environmental Sciences Faculty Publications
Planetary health is an emerging field that emphasises that humans depend on a healthy Earth for survival and, conversely, that the sustainability of Earth systems is dependent on human behaviours. In response to member demands for resources to support teaching and learning related to planetary health, the Consortium of Universities for Global Health (CUGH) convened a working group to develop a set of planetary health learning objectives (PHLOs) that would complement the existing ten CUGH global health learning objectives. The eight PHLOs feature Earth system changes, planetary boundaries, and climate change science; ecological systems and One Health; human health outcomes; …
Claying To Ameliorate Soil Water Repellence, Department Of Primary Industries And Regional Development, Western Australia
Claying To Ameliorate Soil Water Repellence, Department Of Primary Industries And Regional Development, Western Australia
Natural resources factsheets
Claying involves adding and incorporating clay-rich subsoil into water repellent topsoil to overcome the repellence. Adding clay-rich soil provides a long-term solution to soil water repellence, and increases soil water holding capacity, reduces wind erosion risk, and may reduce frost risk.
Claying is best suited to medium to high rainfall environments in Western Australia, with higher crop and pasture yield potential.
Open Groundwater Drains In Wa, Department Of Primary Industries And Regional Development, Western Australia
Open Groundwater Drains In Wa, Department Of Primary Industries And Regional Development, Western Australia
Natural resources factsheets
Open groundwater drains are excavated channels with sloping floors and sides and open levees, designed to intercept and drain surface (usually fresh) and groundwater (usually saline in WA) from agricultural land. These drains are most effective where the channel is dug below a water table in soils that allow good lateral drainage.
DPIRD recommends leveed groundwater drains in most cases. These should form part of a whole farm and whole catchment integrated water and salinity management program. Information on this page is a guide only. It is highly recommended that landholders considering the construction of open drains seek expert advice …
Kentucky Surficial Geologic Map Compilation Database (Version 1), Matthew Massey
Kentucky Surficial Geologic Map Compilation Database (Version 1), Matthew Massey
Research Data--KGS
The Kentucky Geological Survey (KGS), a state-supported independent research center within the University of Kentucky, is committed to providing accurate and unbiased geologic information on natural resources, environmental issues, and natural hazards in Kentucky. While Kentucky boasts complete coverage by 1:24,000-scale geologic bedrock maps, surficial materials have been largely overlooked, except in regions with thick deposits obscuring the bedrock. Given the increasing trends in economic development and urbanization, detailed surficial geologic mapping has become crucial for supporting geotechnical planning, environmental management, and hazard assessment. In response, KGS has prioritized new, detailed surficial geologic mapping since 2004, specifically targeting areas anticipated …
Investigation Of Temperature, Solution Strength, And Applied Stress Effects On Cation Exchange Processes In Different Geosynthetic Clay Liner Products, Kendra Fuller
Master's Theses
An extensive laboratory test program was conducted to analyze and compare the cation exchange processes in three different varieties of sodium bentonite (Na-B) geosynthetic clay liners (GCLs) over increased conditioning durations up to 32 days and investigate the effects of temperature, solution strength, and applied stress. The goal of this test program was to establish whether the variables of temperature, solution strength, and applied stress improved or degraded the engineering properties of GCLs in laboratory testing and municipal solid waste (MSW) landfill applications. The GCLs were conditioned in liquids of increasing ionic strength, using deionized water and 2, 50, and …
Regiongrow3d: A Deterministic Analysis For Characterizing Discrete Three-Dimensional Landslide Source Areas On A Regional Scale, Nicolas W. Mathews, Ben A. Leshchinsky, Benjamin B. Mirus, Michael J. Olsen, Adam M. Booth
Regiongrow3d: A Deterministic Analysis For Characterizing Discrete Three-Dimensional Landslide Source Areas On A Regional Scale, Nicolas W. Mathews, Ben A. Leshchinsky, Benjamin B. Mirus, Michael J. Olsen, Adam M. Booth
Geology Faculty Publications and Presentations
Regional-scale characterization of shallow landslide hazards is important for reducing their destructive impact on society. These hazards are commonly characterized by (a) their location and likelihood using susceptibility maps, (b) landslide size and frequency using geomorphic scaling laws, and (c) the magnitude of disturbance required to cause landslides using initiation thresholds. Typically, this is accomplished through the use of inventories documenting the locations and triggering conditions of previous landslides. In the absence of comprehensive landslide inventories, physics-based slope stability models can be used to estimate landslide initiation potential and provide plausible distributions of landslide characteristics for a range of environmental …
Foliar Diseases And Their Management In Lupins, Department Of Primary Industries And Regional Development, Western Australia
Foliar Diseases And Their Management In Lupins, Department Of Primary Industries And Regional Development, Western Australia
Grains and other field crops factsheets
This factsheet describes symptoms and management of the major fungal and viral diseases affecting lupin foliage, stems, and pods. Several of these diseases have the capacity to cause significant losses if not managed effectively.
Inoculum can be carried in soil, seed, stubble, on green regrowth, or by insect vectors, depending on the disease. Therefore, an integrated approach to disease management is required using tactics such as crop rotation, stubble management, fungicide seed dressing, variety selection, and seed testing
Coastal Flood Risk In The Context Of Climate Change And Urbanization In Northeastern South Carolina, Hongyuan Zhang
Coastal Flood Risk In The Context Of Climate Change And Urbanization In Northeastern South Carolina, Hongyuan Zhang
Electronic Theses and Dissertations
Researchers and the public now widely recognize the seriousness of coastal flood risks. Various changes in natural processes, such as altered rainfall patterns, increased tropical cyclone intensities, and sea-level rise, are consequences of global warming induced by heightened greenhouse gas concentrations. To comprehensively understand coastal compound flooding, it is crucial to consider multiple processes and their interactions. Moreover, the growth of coastal cities and the concentration of people and assets in these areas make them increasingly vulnerable to flooding events. Accurately estimating the future flood risks faced by coastal communities necessitates addressing the compounding effects on coastal flood risk, taking …
Early Season Wheat Response To Electrochemically Precipitated Struvite In Various Soils In The Greenhouse, Tatum Simms, Kristofor R. Brye, Trenton L. Roberts, Lauren F. Greenlee
Early Season Wheat Response To Electrochemically Precipitated Struvite In Various Soils In The Greenhouse, Tatum Simms, Kristofor R. Brye, Trenton L. Roberts, Lauren F. Greenlee
Crop, Soil and Environmental Sciences Faculty Publications and Presentations
Fertilizer-phosphorus (P) materials can be recovered from wastewater and used to supplement mined phosphate rock, where one such material is struvite [MgNH4PO4·6(H2O)]. This study aimed to compare electrochemically precipitated struvite (ECST) reclaimed from synthetic wastewater to other commercial fertilizer-P sources in cultivated soils from Arkansas [silty clay loam (AR-SiCL) and silt loam (AR-SiL)], Missouri [(silt loam; MO-SiL 1 and 2)], and Nebraska [silt loam (NE-SiL) and sandy loam (NE-SL)]. A greenhouse pot study was conducted for 60 days with unvernalized wheat (Triticum aestivum) using five fertilizer-P sources [ECST, chemically precipitated struvite (CPST), monoammonium phosphate (MAP), triple superphosphate (TSP), …
Enhancing Community Flood Resilience By Incorporating Landscape Hydrological Sensitivity And Connectivity, Wenlong Feng
Enhancing Community Flood Resilience By Incorporating Landscape Hydrological Sensitivity And Connectivity, Wenlong Feng
Dissertations
Rapid urban expansion and dramatic climate change have significantly increased the intensity and frequency of floods worldwide. With rising flood risks, conventional flood defense strategies that rely on structural measures become ineffective. The present designations for flood-prone areas, such as FEMA's flood maps, are becoming unreliable. Flood risk management is shifting toward enhancing community flood resilience, highlighting the importance of non-structural approaches. Landscape resilience has become a foundation of community flood resilience. However, past urban development typically undermined natural hydro-ecological functions and landscape resilience because of poor recognition of landscapes' ecological role, hydrological sensitivity, and hydrological connections. This study aims …
Temporal Dynamics Of Coastal Sediment Characteristics: A Comparative Study On Pre- And Post-2004 Tsunami Event Along The Nagoor - Poompuhar Stretch, Tamil Nadu, Yamini S
Theses and Dissertations
Tsunamis represent some of the most devastating natural events for coastal regions, as exemplified by the 26th December 2004 Great Indonesian Earthquake triggered a massive tsunami across the Bay of Bengal and Indian Ocean, causing extensive destruction in various countries, including India. This study addresses a significant gap in the literature by focusing on the detailed sedimentological aspects of coastal dynamics. Specifically, it examines the pre-tsunami (December 2004), post-tsunami (January 2005), and recent (December 2022) sediment characteristics along a 35 km stretch of the Coromandel coast from Poompuhar to Nagoor.
Eight stations were selected for sampling: Poompuhar, Chinnankudi, Kuttyandiyur, Chandrapadi, …
Unveiling Environmental Justice In Two Us Cities Through Greenspace Accessibility And Visible Greenness Exposure, Md Shahinoor Rahman, Mahbubur Meenar, S. M. Labib, Ted Howell, Deepti Adlakha, Ben Woodward
Unveiling Environmental Justice In Two Us Cities Through Greenspace Accessibility And Visible Greenness Exposure, Md Shahinoor Rahman, Mahbubur Meenar, S. M. Labib, Ted Howell, Deepti Adlakha, Ben Woodward
School of Public Health Faculty Publications
Uneven access to greenspaces or visible greenness is an environmental justice (EJ) issue. In this paper, we use a social equity lens to develop geospatial models that measure convenient walking access to urban greenspaces such as parks and street-level green exposure en route to greenspaces. We utilized earth science, geospatial, and demographic datasets to develop two models—Greenspace Accessibility and Visible Greenness Exposure—and applied them in Camden and Jersey City, USA, two communities experiencing environmental injustices. Modeling results show that greenspace accessibility is a concern in both cities, with Jersey City experiencing more prominent disparities. We observed significant positive relationships in …
Foraging Strategies Of Ruminant Livestock On Intensively Managed Grasslands: Potential And Constraints, I J. Gordon, C Lascano
Foraging Strategies Of Ruminant Livestock On Intensively Managed Grasslands: Potential And Constraints, I J. Gordon, C Lascano
IGC Proceedings (1977-2023)
All grazed swards exhibit heterogeneity in the spatial (horizontal and vertical) dispersion of species/biomass. A herbivore foraging at random within such a heterogeneous environment would ingest less nutrients than wou Id one which exploited the heterogeneity on offer through selective grazing. The suite of decision-making processes involved in the selective grazing we observe is termed the animal's foraging strategy. On first observation, intensively managed sown swards appear to offer little opportunity for a herbivore to exhibit a foraging strategy; however, opporlunities do exist and there is empirical evidence that herbivores foraging on sown swards tend to have a diet higher …
Comparative Foraging Strategies Of Grazing Ungulates In African Savanna Grasslands, N Owen-Smith, D H.M Cumming
Comparative Foraging Strategies Of Grazing Ungulates In African Savanna Grasslands, N Owen-Smith, D H.M Cumming
IGC Proceedings (1977-2023)
We review the evolutionary (species-specific) and ecological (individual behavioural) strategies of African grazing ungulates. The contexts considered are free-ranging wild ungulates, traditional livestock pastoralism and extensive commercial ranching. Particularly successful are (1) buffalo, able to digest grass fibre effectively in mesic grasslands; (2) wildebeest, exploiting semi-arid grasslands through migration; (3) megaherbivores (elephant, hippopotamus and white rhinoceros) utilising a wide range of vegetation components. Species-specific adaptations include body size and metabolic rate, digestive efficiency and passage rate, oral and dental anatomy, water dependence and detoxification capacity. Species overlap in grass species se'lected, with dietary differences apparent in grass height favoured, and …
Comparison Of Animal Gains Using Perennial Pastures Exclusively Or Combined With Chicory-Oats-Clover Temporary Winter Pastures, J A. Josifovich
Comparison Of Animal Gains Using Perennial Pastures Exclusively Or Combined With Chicory-Oats-Clover Temporary Winter Pastures, J A. Josifovich
IGC Proceedings (1977-2023)
The increment of winter forage availability using short-rotation pastures could be an interesting way to increase winter carrying capacity. The producer could make good use of higher spring grass production. Sowing oats, rye or chicory alone is quite common in the Argentine Pampa. to evaluate the efficiency of these short-rotation winter pastures a 3 year trial was carried out at Pergamino Experiment Station. The treatments were: a) perennial pastures, 100% of the surface, b) perennial pastures 75%, and chicory-clover 25%, with 2 replications of 3 ha each. The pastures were, for. class II soils, fescue (Festrlca aru11dinacea Schreb.) cv. El …
Influence Of Climatic Factors On Animal Production In The Humid Pampa Of Argentina, J D. Josifovich, E Frutos
Influence Of Climatic Factors On Animal Production In The Humid Pampa Of Argentina, J D. Josifovich, E Frutos
IGC Proceedings (1977-2023)
For any' pasture grazing area it is important lo know the relationship among the climatic parameters, rainfall and temperature, with carrying capacity and minimal gains. The availability of pasture to adjust stocking rates and make provisions for hay or supplementary feed needed for periods of shortage can be estimated from these data. Seven years of monthly rainfall and medium average temperature; and 25 years of forage digestibility and average daily gains were related to cattle i: carrying capacity; Analysis was made using the stepwise regression method. Carrying capacity was evaluated considering animal units (AU) for a 400 kg head gaining …
A New Theory Of Feed Intake Regulation In Ruminants And Its Implications For Forage Quality Research, J.J M.H Ketelaars, B J. Tolkamp
A New Theory Of Feed Intake Regulation In Ruminants And Its Implications For Forage Quality Research, J.J M.H Ketelaars, B J. Tolkamp
IGC Proceedings (1977-2023)
The low voluntary intake of many roughages is commonly explained by a limited physical capacity of ruminants to process fibrous feeds. Recently, we developed a new theory of feed intake regulation assuming feed consumption to create both benefits for the animal (represented by the intake of net energy for maintenance and gain) and costs (represented by the total oxygen consumption of the feeding animal). For nonreproducing ruminants we have shown that voluntary intake of roughages is close to the optimum feed intake level, i.e., the level at which for the animal the ratio between benefits and costs becomes maximum. According …
Botanical Composition Of Forage Samples Selected By Grazing Sheep On The Mountain Rangeland Of Northern China, Han Jianguo, Liu Fuyuan
Botanical Composition Of Forage Samples Selected By Grazing Sheep On The Mountain Rangeland Of Northern China, Han Jianguo, Liu Fuyuan
IGC Proceedings (1977-2023)
Oesophagus fistulae and microscopic examination were used to determine the botanical composition of forage samples selected by grazing sheep on the mountain rangeland in the Hc-Bci Province of northern China during the growing seasons of 1989 and 1990. Results show a clear preference of sheep for some forage species over others. Sheep selected Cleistogenes squarrosa, Koeleria cristata, Potentilla cihinensis, Lespedeza hedysoroides and Scabiosa comosa in each type of rangeland and from early spring to late autumn. The selection ratio of forbs was more than I , and that of grasses less than 1. Sheep showed strong preference for …
The Independent Effects Of Sward Height And Bulk Density On The Bite Parameters Of Romney Ewes And Red Deer Hinds, R J. Mitchell, J Hodgson, D A. Clark
The Independent Effects Of Sward Height And Bulk Density On The Bite Parameters Of Romney Ewes And Red Deer Hinds, R J. Mitchell, J Hodgson, D A. Clark
IGC Proceedings (1977-2023)
The independenl effects of sward height (I, 2, 3, 5 and 8 cm) x bulk density (0.65, 1.30, 2.90 mg DM/cm3) variation on the ingestive behaviour of Romney ewes and Red deer hinds were examined in seedling swards which simulated a leafy grass sward of low shear strength. Depth of penetration, horizontal area of herbage severed per bite, weight of each bite and the rate of intake all increased with increasing height, while the rate of biting decreased (P
Relationships Between Milk Yield, Pasture On Offer And Diet Selection In Tropical Grass Pastures, T M. Davison, W N. Orr, V J. Doogan, K Lowe
Relationships Between Milk Yield, Pasture On Offer And Diet Selection In Tropical Grass Pastures, T M. Davison, W N. Orr, V J. Doogan, K Lowe
IGC Proceedings (1977-2023)
A 7-year study was conducted with Holstein-Friesian cows to determine responses to different levels of nitrogen and phosphorus fertiliser applied to Gatton panic (Panicum maximum cv. Gatton) pastures. This study was used to develop relationships between milk yield, pasture and diet botanical components. Multiple regression analysis revealed there was: a negative relation between stem yield (SI) on offer in summer (S) and milk yield but a positive association with leaf yield (L) on offer in summer and green dry matter .GDM in autumn (A),, MY = 2279.0+0.529 LS-0.246 StS+0.324 GDMA _(R2 = 0.66; P
A New Ambulatory Data-Logging System For A Long Term Determination Of Grazing And Rumination Behavior On Free Ranging Cattle, Kanji Matsui, Tadakatu Okubo
A New Ambulatory Data-Logging System For A Long Term Determination Of Grazing And Rumination Behavior On Free Ranging Cattle, Kanji Matsui, Tadakatu Okubo
IGC Proceedings (1977-2023)
A new ambulatory apparatus (named "jaw recorder") has been developed. The apparatus has a large data storage capacity (32 768 data points), and enables data to be recorded every minute for a minimum of 22 days in one recording session. A Holstein heifer was fitted with the apparatus and was grazed with 4 other heifers for 13 days on a pasture of 0.36 ha of Italian ryegrass (Lolium nmltiflorum Lam.). Grazing and rumination period could be distinguished by a combination of jaw movements and pauses between jaw movements longer than 3 sec/min. Grazing and rumination time distinctly increased with …
Field Test Of Optimal Foraging With Cattle: The Marginal Value Theorem Predicts Patch Selection And Utilization, Emilio A. Laca, R A. Distel, T C. Griggs, G Deo, M W. Demment
Field Test Of Optimal Foraging With Cattle: The Marginal Value Theorem Predicts Patch Selection And Utilization, Emilio A. Laca, R A. Distel, T C. Griggs, G Deo, M W. Demment
IGC Proceedings (1977-2023)
Grazers selectively forage within heterogeneous vegetation. Prediction of intake rate necessitates theoretical developments to understand site selection. We tested III optimal foraging model to predict patch selection by cattle in the field, Nine "grazing environments" (GB) consisting of 16 0.36 m2 patches each were created by mowing. Treatments were a factorial of 3 distances between patches and 3 sets of patch heights. Patch residence time (T,) was accurately predicted (r2=0.89), and increased linearly whh patch distance (P
A Conceptual Model To Explain Variation In Ingestive Behavior Within A Feeding Patch, Emilio M. Laca, M W. Demment, R A. Distel, T C. Griggs
A Conceptual Model To Explain Variation In Ingestive Behavior Within A Feeding Patch, Emilio M. Laca, M W. Demment, R A. Distel, T C. Griggs
IGC Proceedings (1977-2023)
A conceptual model is presented that links the mechanics of bite formation to the characteristics of the sward to explain variation in bite weight, bite area, bite depth and biting rate measured in a series of experiments with hand-constructed swards. Bite area is determined by the behaviour used by the animal to collect and grasp the tillers, and the length and stiffness of the sward, Bite depth is affected by height and the degree of vertical heterogeneity in stiffness. Time per bite is controlled by bite weight. These mechanisms of bite formation and time per bite ex.plain many observed effects, …
Selective Behaviour Of Cattle Grazing Ryegrass Swards With Horizontal Heterogeneity In Patch Height And Bulk Density, Montague W. Demment, R A. Distel, T C. Griggs, E A. Laca, G P. Deo
Selective Behaviour Of Cattle Grazing Ryegrass Swards With Horizontal Heterogeneity In Patch Height And Bulk Density, Montague W. Demment, R A. Distel, T C. Griggs, E A. Laca, G P. Deo
IGC Proceedings (1977-2023)
Patches of different height and/or bulk density were created in ryegrass pasture to study selective responses of steers to horizontal variability in patch structure. The experiment involved 3 heterogeneity treatments with 2 patch types each. Steers encountered and entered both patch types available in each treatment with the same frequency. In contrast, they grazed for a longer time (T,) at; and removed more bites (B) from the patch type that yielded greater intake rates. While T, and B varied for a patch type depending on the alternative patch, bite rate and likely bite size were constant for a given patch …
Computer Recording Of The Variation In Intake Of Supplements Provided To Grazing Cattler, R M. Tait, L J. Fisher
Computer Recording Of The Variation In Intake Of Supplements Provided To Grazing Cattler, R M. Tait, L J. Fisher
IGC Proceedings (1977-2023)
A computer system has been developed to record the consumption of' supplements provided free choice to grazing cattle. The system is based on electronic animal identification and one or more weatherproof electronic scales located in simple feed stations connected by telephone cable to a computer at a distance of up to 1 km. The software program identifies and records individual animals, • time and duration of visits, and the quantity of supplement consumed. The system has been tested in the field using 40 kg molasses-based feed blocks with up to 20 steers per feed station in paddocks of approximately 4 …
Diet Selection By Lambs In Ryegrass-White Clover Swards Differing In The Horizontal Distribution Of Clover, R H. Armstrong, E Robertson, C S. Lamb, I J. Gordon, D A. Elston
Diet Selection By Lambs In Ryegrass-White Clover Swards Differing In The Horizontal Distribution Of Clover, R H. Armstrong, E Robertson, C S. Lamb, I J. Gordon, D A. Elston
IGC Proceedings (1977-2023)
Weaned 5-month-old lambs grazed 2 series of perennial ryegrass (Lolium perenne L.) plots containing patches of mixed perennial ryegrass and white clover (Trifolium repens L.) varying in either a) the size of patches or b) the distance between patches. Both series embraced the same range of percentages (1-25) of ryegrass-clover patches in each plot. Diet composition was estimated from the pattern of naturAI alkanes in faeces collected between days 6 to 15 after allocation of the lambs to the treatments. The percentage of clover in the diet declined markedly from days 6 to 11 and thereafter increased slightly. Dietary …
Influence Of Ectoparasites On Ingestive And Meristic Behavior Of Grazing Beef Cattle, C T. Dougherty, F W. Knapp, P B. Burrus, N W. Bradley
Influence Of Ectoparasites On Ingestive And Meristic Behavior Of Grazing Beef Cattle, C T. Dougherty, F W. Knapp, P B. Burrus, N W. Bradley
IGC Proceedings (1977-2023)
Face flies (Musca autumnalis De Geer) and slable flies (Stomoxys calcitrans L.) were raised in the laboralory and released into 12 enclosures, each with I grazing cow (Bos taurus L.). Releases of 0, 400 and 800 face flies gave 3, 53 and 64 lighted flies/cow, respectively, with 30/head al the 400 and 800 levels, and eliciled head (2, 60 and 39/h), ears (8, 1337 and 859/h), tails (24, 191 and 606/h) movements and skin twitches (1 side) (15, 210 and 248/h) but did not induce leg movements or affect number of feeding stations visited (188/h), Face flies …
Dung Bags To Prevent Dung Pat Formation In Pasture By Grazing Cattle, Sakurai Mosaku
Dung Bags To Prevent Dung Pat Formation In Pasture By Grazing Cattle, Sakurai Mosaku
IGC Proceedings (1977-2023)
In order to prevent dung pat formation on intensively grazed pasture in the humid temperate zone, a modified dung bag was made. Results from a preliminary study showed that smaller dung lumps dropped in the pasture resulted in the period of rejection being shorter and the rejected area being smaller or non existent. The dung bag was remodeled and fitted to the milking cows. After excretion the dung is held in the dung bag. From a hole in the bottom of the bag smaller dung lumps fall to the pasture. Therefore larger dung pat formation is prevented and the area …