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Articles 2881 - 2910 of 17275
Full-Text Articles in Entire DC Network
Comparison Between Fodder Cropping Rotations Carried With Or Without Meadow In The Intensive Farming System Of The Po Valley Plain (Italy), Mario Onofrii, Cesare Tomasoni, Lamberto Borrelli
Comparison Between Fodder Cropping Rotations Carried With Or Without Meadow In The Intensive Farming System Of The Po Valley Plain (Italy), Mario Onofrii, Cesare Tomasoni, Lamberto Borrelli
IGC Proceedings (1977-2023)
Pour fodder cropping rotations were compared at different degrees of crop intensification: (RI) a I-year continuous monoculture of Italian ryegrass (Loll111n multij/orum Lam.) +silage maize (Zea mays L.); (R3) a 3-year rotation of Italian ryegrass+silage maize - barley (Hordeum vulgare L.)+silage mai1:e - grain maize; (R6) a 6-year rotation of Italian ryegrass+silage maize for 3 years followed by meadow for 3 years (Trifolium repe11s L. + Festuca ari111di11acea Schreb,): (PM) a monoculture of permanent meadow. The most efficient rotation for dairy cattle feeding, on sandy-loam soils, was the I-year rotation of Italian ryegrass, followed by silage maize, with 22 9S0 …
Cadmium In Soil, Pasture And Grazing Ruminants, J Lee, N D. Grace, A D. Mackay, M J. Hedley, J R. Rouce
Cadmium In Soil, Pasture And Grazing Ruminants, J Lee, N D. Grace, A D. Mackay, M J. Hedley, J R. Rouce
IGC Proceedings (1977-2023)
Cadmium, present in New Zealand hill country pastures rrom Cdamended phosphatic fertiliser use, is assimilated by grazing ruminants. Concentrations of Cd in plasma from sheep grazing pastures containing low (0.1-0.2µglg dry weight) or high (0.8-1.4 µgig dry weight) levels of Cd were 0.15±0.04 nglg and 0,35:1:0.15 ng/g, respectively (P<0.08). Cadmium in pasture was highly correlated (P<0,001) with soil O.IM HCl-extractable Cd (log10 Soiled= -0.98+0.26 Plantcd).
Nitrogen Dynamics In Three Contrasting Grassland Systems: Implications For Pasture Productivity And The Potential For Environmental Pollution, B E. Ruz-Jerez, R E. White, P Roger Ball
Nitrogen Dynamics In Three Contrasting Grassland Systems: Implications For Pasture Productivity And The Potential For Environmental Pollution, B E. Ruz-Jerez, R E. White, P Roger Ball
IGC Proceedings (1977-2023)
Nitrogen (N) dynamics were compared in 3 contrasting grassland systems (2 legume-based and I receiving fertiliser N) in a cool temperate region of New Zealand. The study was concentrated on the various N transfers that occurred during and after grazing. Critical periods for N loss by different processes have been identified, allowing a more comprehensive understanding of the role of N in the productivity of different types of pasture, and the potential for environmental pollution, Calculation of N inputs and outputs for the three pastures indicated that the two legume-based systems were more or less in balance, but in the …
Reduction Of Nutrient Losses For Dairy Farms, With Emphasis On Nitrogen, W Luten, D J. Den Boer
Reduction Of Nutrient Losses For Dairy Farms, With Emphasis On Nitrogen, W Luten, D J. Den Boer
IGC Proceedings (1977-2023)
Recently the Dutch government presented several policy papers in which standards are given for maximum allowed emissions to air, groundwater and surface water. Depending on the farm situation an optimum combination of measures in relation to housing, slurry storage, slurry and fertiliser application, and composition of the ration can be taken. In general a better use of nutrients from animal manure by applying slurry with low emission techniques in the growing season and a reduction of the stocking rate by a higher milk production per cow are the most effective and cheapest measures to reach these targets. There is a …
Use Of Pasture As A Receivers For Swine Lagoon Effluent, J P. Mueller, J C. Barker, J P. Zublena, M H. Poore, R W. Harvey, J T. Green
Use Of Pasture As A Receivers For Swine Lagoon Effluent, J P. Mueller, J C. Barker, J P. Zublena, M H. Poore, R W. Harvey, J T. Green
IGC Proceedings (1977-2023)
Swine waste management-cattle grazing systems were monitored on 2 North Carolina farms from 1990-1992, Farmers co-operated directly in the project by furnishing land, labour, equipment and cattle and by maintaining records of grazing and waste applications. Local county agricultural extension agents helped with management decisions, recordkeeping and co-ordinating activities among project participants. On a fann where waste was applied to pastures for 5 years, soil N in the upper l m averaged from 230-500 kg/ha, NO3 -N in the forage remained above 10 g/kg for the grazing season and 2 of 4 test wells recorded NO3 levels above 10 mg/I. …
Pastoral Systems Of Central Himalaya: How Long Will They Survive?, K S. Rao, K G. Saxena
Pastoral Systems Of Central Himalaya: How Long Will They Survive?, K S. Rao, K G. Saxena
IGC Proceedings (1977-2023)
Pastoral systems of Central Himalaya are very old and until recent time were in balance with environment, Recent changes in sociopolitical setup have drastically altered the status of these systems. The change of political power in trans-Himalayan Tibetean plateau has resulted in closure of international boarders, thus taking away the mercantile aspects of pastoralists and reducing pastoral area. Increased human disturbances on fragile Himalayan marginal lands and excessive onslaught on forests for fuel and fodder by the sedentary population has resulted in degradation and non-productive grasslands which do not help pastoralists sustain existing systems. Changes in relations between migratory pastoralists …
A Preliminary Discussion Of The Management And Administration Of Yunwu Mountain Natural Grassland Reserve In China, Zhao Zhiyi, Yang Ailian
A Preliminary Discussion Of The Management And Administration Of Yunwu Mountain Natural Grassland Reserve In China, Zhao Zhiyi, Yang Ailian
IGC Proceedings (1977-2023)
The advantages and problems encountered in the establishment of a grassland reserve are described. The conflicts between local farmers' requirement to feed and water livestock and the conservation strategy of natural grassland are discussed.
Effect Of Sewage Sludge On The Mineral Composition Of Corn, Arthur E. Peterson, P E. Speth, P L. Schlecht
Effect Of Sewage Sludge On The Mineral Composition Of Corn, Arthur E. Peterson, P E. Speth, P L. Schlecht
IGC Proceedings (1977-2023)
For the past 12 years, digested sewage sludge from the Milwaukee Metropolitan Sewerage District has been applied to a Plano silt loam (prairie) soil near Elkhorn, Wisconsin, and corn raised as the indicator crop. The corn has been harvested as silage and fed to dairy cnttle. The amounts of macro-, micro-, and heavy metals contained in this forage were compared with the amounts contained in the untreated areas, and in the forage produced by a sustainable agriculture study on the same experimental station. None of the heavy metals have moved out of the plough layer (lop 25 cm). The uptake …
Sustainable Direction For Resource Management An Assessment Of The Regional Council Role, Allan Lohrey
Sustainable Direction For Resource Management An Assessment Of The Regional Council Role, Allan Lohrey
IGC Proceedings (1977-2023)
The 1980s has seen an increased world awareness of the concept of sustainability. In 1991 New Zealand enacted the Resource Management Act (RMA) which reflected society's concern for a need to consider future generations when making decisions relating to the use of natural resources. Regional councils have been allocated the role within the Act to promote sustainable management at the regional level. The short term challenge to regional councils is to manage resources in manner which strikes a pragmatic balance between the ongoing needs of society and the need to provide resources for future generations. Regional councils will know they …
Application Of Dairy Manure On Alfalfa, Stephen J. Herbert, Jayarm Daliparthy, P L.M Veneman
Application Of Dairy Manure On Alfalfa, Stephen J. Herbert, Jayarm Daliparthy, P L.M Veneman
IGC Proceedings (1977-2023)
Applying dairy manure to alfalfa (Medicago sativa L.) as ,in alternative 10 excess application to· corn (Zea mays L.) may reduce nitrate pollution of groundwater. Field experiments were conducted at 2 sites in Massachusetts, USA, lo study the impact or dairy manure application to alfalfa on forage yield, weed infestation· and nitrate movement. Treatments were an unfertilized (no N) check.· plot, low and high manure (112 and 336 kg N/ha/year equivalerit), and low and high N fertiliser (112 and 336 kg N/ha/year from NH4NO3),'. Liquid dairy manure was applied 10 • alfalfa immediately· after 1st· cutting during spring …
Microfiltration Membrane Pore Functionalization With Primary And Quaternary Amines For Pfas Remediation: Capture, Regeneration, And Reuse, Sam Thompson, Angela Gutierrez, Jennifer Bukowski, Dibakar Bhattacharyya
Microfiltration Membrane Pore Functionalization With Primary And Quaternary Amines For Pfas Remediation: Capture, Regeneration, And Reuse, Sam Thompson, Angela Gutierrez, Jennifer Bukowski, Dibakar Bhattacharyya
UK CARES Faculty Publications
The widespread production and use of multi-fluorinated carbon-based substances for a variety of purposes has contributed to the contamination of the global water supply in recent decades. Conventional wastewater treatment can reduce contaminants to acceptable levels, but the concen- trated retentate stream is still a burden to the environment. A selective anion-exchange membrane capable of capture and controlled release could further concentrate necessary contaminants, mak- ing their eventual degradation or long-term storage easier. To this end, commercial microfiltration membranes were modified using pore functionalization to incorporate an anion-exchange moiety within the membrane matrix. This functionalization was performed with primary and …
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; …
Coal Ash Triggers An Elevated Temperature Landfill Development: Lessons From The Bristol Virginia Solid Waste Landfill Neighboring Community, Reagan Patton Witt, Marcelo I. Guzman
Coal Ash Triggers An Elevated Temperature Landfill Development: Lessons From The Bristol Virginia Solid Waste Landfill Neighboring Community, Reagan Patton Witt, Marcelo I. Guzman
UK CARES Faculty Publications
Landfills for disposing of solid waste are designed, located, managed, and monitored facili- ties expected to comply with government regulations to prevent contamination of the surrounding environment. After the average life expectancy of a typical landfill (30 to 50 years), a large investment in the construction, operation, final closure, and 30-year monitoring of a new site is needed. In this case study, we provide a holistic explanation of the unexpected development of elevated temperature landfills (ETLFs), such as that in the city of Bristol (United States) on the border of the states of Virginia and Tennessee, including the initial role …
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 …
Investigating Effectiveness Of Inverted Classroom In Undergraduate Statistics Education, Xin Ma, Jing Zhang, Petya Karkelanova, Michael C. Osborne, Anushka Karkelanova
Investigating Effectiveness Of Inverted Classroom In Undergraduate Statistics Education, Xin Ma, Jing Zhang, Petya Karkelanova, Michael C. Osborne, Anushka Karkelanova
Educational, School, and Counseling Psychology Faculty Publications
Data collected from an educational experiment were analyzed to investigate the effectiveness of an instructional reform referred to as the inverted classroom (learning activities traditionally taking place inside the classroom now take place outside the classroom and vice versa) in undergraduate statistics education. Students were taught the same statistics course in the inverted classroom (135 students) and the traditional classroom (135 students) over one semester. A small sample HLM (hierarchical linear modeling) approach was used to account for the data structure of students nested within 12 sections of the course and small sample sizes at both student and section levels. …
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 …