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The Potential Importance Of Microenvironment On Polymer Bound Chemical Reagents, Nathan Joseph Halsteter Jul 2025

The Potential Importance Of Microenvironment On Polymer Bound Chemical Reagents, Nathan Joseph Halsteter

Theses and Dissertations

In this thesis will provide a brief history of polymer bound reagents, their uses, and advancements. The importance of polymer microenvironments will be explored using a model kinetic resolution reaction utilizing polymer bound reagents to observe how changes in a polymer’s microenvironment effects the yield and selectivity of a reaction. It was found that there are copious factors that affect polymer bound reagents, and no direct conclusion could be drawn from the study.


Characterizing Dissolved Organic Matter Composition In A Southeastern United States Watershed, Gwendolyn Marcelette Hopper Jul 2025

Characterizing Dissolved Organic Matter Composition In A Southeastern United States Watershed, Gwendolyn Marcelette Hopper

Theses and Dissertations

Dissolved organic matter (DOM) has important roles in many biogeochemical cycles. DOM is primarily composed of dissolved organic carbon (DOC), nitrogen, and phosphorus, and the processing of DOM is important for nutrient regulation and carbon cycling. In the coastal plains of the southeastern United States, there are many rivers and streams known as “blackwaters” with exceptionally high concentrations of chromophoric dissolved organic matter (CDOM) leached from terrestrial soils, coinciding with a region experiencing some of the nation’s highest rates of development. As changes in land use and climate continue to occur, DOM composition from natural to anthropogenically impacted systems can …


Enhancing Phenotyping Accuracy For Selection Of Urochloa Spp. Tolerant Genotypes To Red Spider Mite (Oligonychus Trichardti), Paula Espitia-Buitrago, José Miguel Cotes Torres, Luis Miguel Hernández, Juan Andres Cardoso, Frank Chidawanyika, Rosa N. Jauregui Jul 2025

Enhancing Phenotyping Accuracy For Selection Of Urochloa Spp. Tolerant Genotypes To Red Spider Mite (Oligonychus Trichardti), Paula Espitia-Buitrago, José Miguel Cotes Torres, Luis Miguel Hernández, Juan Andres Cardoso, Frank Chidawanyika, Rosa N. Jauregui

All Peer-Reviewed Publications

The red spider mites are a major biotic limitation to productivity for Brachiaria (Urochloa spp.) grasses in tropical Eastern Africa, causing severe economic losses mainly in the dry seasons. However, due to the lack of reports of integrated pest management strategies, genetic resistance can play a crucial role in Brachiaria-based livestock systems, minimising the impact of this pest. The objective of this study was to develop and validate a methodology for accurately categorising resistance responses in Urochloa genotypes to identify potential sources of resistance to the Western Kenya red spider mite Oligonychus trichardti (Meyer 1974). Accordingly, 25 genotypes of Urochloa …


Regression With Atypical Data: Measurement Error, Periodicity, And Non-Normality, Nicholas W. Woolsey Jul 2025

Regression With Atypical Data: Measurement Error, Periodicity, And Non-Normality, Nicholas W. Woolsey

Theses and Dissertations

Regression is a ubiquitous and fundamental method that can be found in any ele- mentary statistics course. The simplicity and self evidently useful nature of linear regression beguiles a non-negligible portion of researchers into disrespecting assump- tions required by these models, namely in terms of accuracy of covariates and the underlying nature of the data. This disregard can at best lead to meaningless results and at worse cause significant misunderstandings in scientific pursuit.

In this dissertation we strive propose remedies to violations of specific assump- tions. Namely the assumptions that covariates are either observed without measure- ment error or they …


Winds Of Change: Charting A Pathway To Ecosystem Monitoring Using Airborne Environmental Dna, Rachel L. Tulloch, Clare I.M. Adams, Matthew A. Barnes, Elizabeth L. Clare, Henrik C. Van De Ven, Andrew Cridge, Francisco Encinas-Viso, Kristen Fernandes, Dianne M. Gleeson, Erin Hill, Anna J.M. Hopkins, Anna M. Kearns, Gracie C. Kroos, Anna J. Macdonald, Francesco Martoni, Angela Mcgaughran, Todd G.B. Mclay, Linda E. Neaves, Paul Nevill, Andrew Pugh, Kye J. Robinson, Fabian Roger, Tracey V. Steinrucken, Mieke Van Der Heyde, Cecilia Villacorta-Rath, Jenny Vivian Jul 2025

Winds Of Change: Charting A Pathway To Ecosystem Monitoring Using Airborne Environmental Dna, Rachel L. Tulloch, Clare I.M. Adams, Matthew A. Barnes, Elizabeth L. Clare, Henrik C. Van De Ven, Andrew Cridge, Francisco Encinas-Viso, Kristen Fernandes, Dianne M. Gleeson, Erin Hill, Anna J.M. Hopkins, Anna M. Kearns, Gracie C. Kroos, Anna J. Macdonald, Francesco Martoni, Angela Mcgaughran, Todd G.B. Mclay, Linda E. Neaves, Paul Nevill, Andrew Pugh, Kye J. Robinson, Fabian Roger, Tracey V. Steinrucken, Mieke Van Der Heyde, Cecilia Villacorta-Rath, Jenny Vivian

Research outputs 2022 to 2026

Airborne environmental DNA (airborne eDNA) analysis leverages the globally ubiquitous medium of air to deliver broad species distribution data and support ecosystem monitoring across diverse environments. As this emerging technology matures, addressing critical challenges and seizing key opportunities will be essential to fully realize its potentially transformative impact. In June 2024, the Southern eDNA Society convened over 100 researchers, industry leaders, and biodiversity management stakeholders in a landmark workshop to evaluate the current state of airborne eDNA research and chart a course for future development. Participants explored opportunities for integrating airborne eDNA into existing monitoring systems, but they unanimously agreed …


Behavioral Responses Of The California Two-Spot Octopus Octopus Bimaculoides To Changes In Color And Sound, Sofia I. Ramirez, Nathalie Reyns Jul 2025

Behavioral Responses Of The California Two-Spot Octopus Octopus Bimaculoides To Changes In Color And Sound, Sofia I. Ramirez, Nathalie Reyns

McNair Summer Research Program

Recreational and commercial boat activity, military and construction operations, and seismic surveys among other human activities produce excessive sound that is classified as anthropogenic noise. Because the intensity and frequency of anthropogenic noise is often higher than that of natural underwater acoustic stimuli, marine animals may experience physiological damage to their sound-detecting organs which in turn, affects their communication and orientation abilities. In our study, we aimed to analyze the differences in behaviors exhibited by the California two-spot octopus (Octopus bimaculoides) when exposed to various volumes of noise at 54 Hz. To further investigate behavioral changes under varying conditions, we …


O-Mapl: Offline Multi-Agent Preference Learning, The Viet Bui, Tien Mai, Hong Thanh Nguyen Jul 2025

O-Mapl: Offline Multi-Agent Preference Learning, The Viet Bui, Tien Mai, Hong Thanh Nguyen

Research Collection School Of Computing and Information Systems

Inferring reward functions from demonstrations is a key challenge in reinforcement learning (RL), particularly in multi-agent RL (MARL). The large joint state-action spaces and intricate inter-agent interactions in MARL make inferring the joint reward function especially challenging. While prior studies in single-agent settings have explored ways to recover reward functions and expert policies from human preference feedback, such studies in MARL remain limited. Existing methods typically combine two separate stages, supervised reward learning, and standard MARL algorithms, leading to unstable training processes. In this work, we exploit the inherent connection between reward functions and Q functions in cooperative MARL to …


Increasing Flora Diversity In Grassland Swards, R J. Haggar, D Jones Jun 2025

Increasing Flora Diversity In Grassland Swards, R J. Haggar, D Jones

IGC Proceedings (1977-2023)

Europe's farmers are being encouraged to take land out of agriculture in order to reduce surplus cereal production. There is therefore, increasing scope for creating new species-rich swards, although guidelines for this purpose are lacking. Several reasons are advanced for encouraging species diver­sity and conservation, including recreational, ethical, education and resource utilisation. As leisure time increases, so public interest in conservation matters increases. Scientifically, there is a need to preserve genetic diversity and to understand the com­plex plant and animal relationship leading to a rich and varied community. This paper describes two experiments aimed at achieving a . highly diverse …


Multiple Of The Intermountain Region, Forest Service, United States Department Of Agriculture, J S. Tixier, A H. Winward Jun 2025

Multiple Of The Intermountain Region, Forest Service, United States Department Of Agriculture, J S. Tixier, A H. Winward

IGC Proceedings (1977-2023)

Initial custodians of the National Forests of the United States were primarily concerned about protecting what were perceived as deteriorating timber stands and watersheds. Con­siderable progress was made in correcting these problems in the first half of this Century. As the population of the United States grew, more people became interested in management of all resources on these public lands. Forest Officers gradually became stewards managing a broad array of lands and resources for which there were often conflicting interests and uses. A primary use of National Forests in the Western United States has been livestock grazing. Here, animals are …


Fringed Sagebrush, Ming Chang Wang Jun 2025

Fringed Sagebrush, Ming Chang Wang

IGC Proceedings (1977-2023)

Fringed sagebruch (Artemisia frigida will) is one of the common plants in inner mongolia plateau. It was recognized as an excellent perennial herbaceous plants accunting for a large proportion in wild vegetation. Fringed sagebruch belongs to composites, Semi-frutex, tomentellate in whole plant, tap root may be 100 cm deep in the soil. Fringed sagebrush distributed to the north of the Yellow River in China, Fareast and Caucasus in USSR, Mongolia and Canada. Fringed sagebruch is an excellent forage for horses, cattle, sheep, goats and Camels. The animals will get gain if fringed sagebruch is fed.


Assessment Of Agronomic Performance Of Large Numbers Of Plant Accessions Using A Computerized Data Management System, D A. Ivory, A Ella, J Nulik, R Salam, M E. Siregar, S Yuhaeni Jun 2025

Assessment Of Agronomic Performance Of Large Numbers Of Plant Accessions Using A Computerized Data Management System, D A. Ivory, A Ella, J Nulik, R Salam, M E. Siregar, S Yuhaeni

IGC Proceedings (1977-2023)

A major research effort has been directed to finding suitable forage species for animal production in various regions of Indonesia. The two difficulties common to most preliminary evaluation studies of large numbers of diverse groups of forage plants is in deciding firstly what plant attributes should be assessed and secondly, the methods to be used in the management and analysis of large masses of data. A set of minimum plant attributes has been used for both grasses, herbaceous legumes and tree legumes in experiments at a number of key testing sites in Indonesia. A computerized system of data management from …


Forage Attributes Of The Perennial Groundnut Arachis Pintoi In A Tropical Savanna Environment In Colombia, B Grof Jun 2025

Forage Attributes Of The Perennial Groundnut Arachis Pintoi In A Tropical Savanna Environment In Colombia, B Grof

IGC Proceedings (1977-2023)

In the continuing search for superior germplasm of tropical legumes adapted to Oxisol savanna conditions, a study of the perennial wild species of groundnut (peanut), Arachis pintoi, was initiated at Carimagua Research Station on the eastern plains (Llanos Orientales) of Colombia. A pintoiis an agronomically little-known legume pasture species indigenous to South America. Its performance in grazed association with four different Brachiaria spp. was evaluated in terms of dry matter yield and animal weight gain. A. pintoi was successful under conditions of heavy grazing (2.4 animal units/ha) employed on a year-round basis. Total grass and legume dry matter (DM) yields …


The Effect Of Previous Experience Of Animals On Subsequent Preference In A Palatability Grazing Trial, C Lascano, P Hoyos, R Schultze-Kraft, M C. Amexquita Jun 2025

The Effect Of Previous Experience Of Animals On Subsequent Preference In A Palatability Grazing Trial, C Lascano, P Hoyos, R Schultze-Kraft, M C. Amexquita

IGC Proceedings (1977-2023)

Previous experience of test animals has been mentioned as a factor which may affect grazing preference of cattle. Palatability trials have usually been conducted without allowing animals to previously graze individual forage species under evaluation. A cafeteria trial was designed to study the effect of previous grazing of individual species in the palatability ranking of six tropical legumes. Results indicated that short-term previous experience of the test animals affected the magnitude of the palatability index of the most palatable legume on the first days of the trial, but did not affect the overall palatability ranking of species. Therefore, it would …


Aeschynomeme - A Legume Genus With Potential For The Australian Tropics, H G. Bishop, B Walker, D H. Ludke, M T. Rutherford Jun 2025

Aeschynomeme - A Legume Genus With Potential For The Australian Tropics, H G. Bishop, B Walker, D H. Ludke, M T. Rutherford

IGC Proceedings (1977-2023)

Aeschynomene spp. have been identified as a promising group of legumes adapted to seasonally waterlogged soils on the central Queensland wet coast. Near Mackay (1470 mm M.A.R.) the legume component of Macroptilium atropurpureum cv. Siratro/Setaria sphacelala var. sericea cv. Kazungula pastures on adequately fertilized solodic soils, did not persist under heavy grazing (2.5 and 2.0 steers/ha), whereas the native legume Aeschynomene indica persisted and gave yields up to 1401 kg/ha. At light stocking rates siratro persisted, whereas frequency and yields of A indica were negligible. After an introduction and evaluation programme, A. americana CPI 58491 was released in 1983 …


Summer Forage Legume Introduction In Louisiana, A M. Thro, C C. Shock Jun 2025

Summer Forage Legume Introduction In Louisiana, A M. Thro, C C. Shock

IGC Proceedings (1977-2023)

Climate in Louisiana is influenced by tropical air masses in summer and alternately by tropical and continental air masses in winter. From northwest to southeast, the number of frost-free growing days increases from 230 to 350. Rainfall increase from 1200 mm to 1500 mm and is evenly distributed winter through summer with a generally drier fall. Livestock production is an important economic activity throughout the state. Animal performance declines from July through November in spite of adequate availability of perennial grass forage. A summer-growing forage legume is sought that will persist in perennial grass pastures and provide a more easily …


A Study Of Phenology, Herbage Yield And Crude Protein Content Of Native Ecotypes Of Red Bromegrasses (Bromus Tomentellus Boiss.) Of Iran, B Peymani-Fard Jun 2025

A Study Of Phenology, Herbage Yield And Crude Protein Content Of Native Ecotypes Of Red Bromegrasses (Bromus Tomentellus Boiss.) Of Iran, B Peymani-Fard

IGC Proceedings (1977-2023)

This research was conducted on ten ecotypes of red bromegrasses of Iran at Homand Range Experiment Station, near Damavand, Iran to asses: (a) the differences in phenological characteristics, (b) to evaluate differences in herbage yield, and (c) determine the crude protein percentage Parameters measured include duration of vegetative, heading, maturity stages, herbage yields, and crude protein. Variation in vegetative growth, heading and seed maturity stages among the ecotypes under study was very small

Therefore, there are no prefences in selection of a specific ecotype from the standpoint of utilization and harvesting time. There was a great fluctuation in annual herbage …


Exploring Students’ Perceptions Of Science Laboratory Practices: A Comparative Study Between Rural And Urban Schools, Safrida Dwiningsih, Ina Lestari, Roma Ismi, Sri Wahyu Rahmadina, Masdalena Sinaga, M. Rahmad Jun 2025

Exploring Students’ Perceptions Of Science Laboratory Practices: A Comparative Study Between Rural And Urban Schools, Safrida Dwiningsih, Ina Lestari, Roma Ismi, Sri Wahyu Rahmadina, Masdalena Sinaga, M. Rahmad

Jurnal Pendidikan Sains

This study aims to analyze students' perceptions of the implementation of science laboratory practicums at public middle school 020 Pekanbaru and public middle school 7 Pangkalan Kuras, Riau Province. Using a quantitative survey method, this study involved 75 student respondents. The instrument used was a questionnaire consisting of 26 statements, analyzed descriptively. The results show that students' perceptions of the preparation, implementation, and conclusion stages of the practicum fall into the "good" category, with urban schools having a higher percentage. In conclusion, the implementation of practicums in urban schools is better than in rural schools, bringing attention to the need …


Digital Comic Learning Media (E-Comic) To Increase Student Learning Interest In Reaction Rate Material At High School, Berliana Afsohin Nabila, Achmad Lutfi Jun 2025

Digital Comic Learning Media (E-Comic) To Increase Student Learning Interest In Reaction Rate Material At High School, Berliana Afsohin Nabila, Achmad Lutfi

Jurnal Pendidikan Sains

This study aims to develop digital comic learning media that is effective in increasing students' interest in learning about reaction rate material, focusing on the media's validity, practicality, and overall effectiveness. This research utilizes the research and development method with the ADDIE model. Research instruments were used, including validity sheets to assess the media's validity, student activity observations, and student response questionnaires to evaluate the media's practicality, as well as student interest questionnaires and learning outcomes to measure the effectiveness of the learning media. The findings show that validity results showed a mode score of 4, indicating a very valid …


The Effort To Improve Students’ Problem-Solving Ability: Physics E-Modules For High School Students, Hidayatullah Hana Putra, Edi Supriana, Nasikhuddin Nasikhuddin, Annisa U. Yana, Suhailee Sohnui Jun 2025

The Effort To Improve Students’ Problem-Solving Ability: Physics E-Modules For High School Students, Hidayatullah Hana Putra, Edi Supriana, Nasikhuddin Nasikhuddin, Annisa U. Yana, Suhailee Sohnui

Jurnal Pendidikan Sains

Physics teachers in Indonesia still face obstacles during learning, such as students who are less active and have difficulty in solving physics problems. The physics learning media used are also still not very interesting and are not based on authentic problem solving. Therefore, this study focuses on the development of PBL-based e-modules on work and energy to improve the physics problem-solving abilities of high school students. This research and development used the ADDIE design and was tested on 90 high school students in High School 1 Sumber Pucung Malang in the 2022/2023 academic year. The questionnaire instrument was used in …


Vitamin D3 Toxicity-Induced Hypercalcemia In Staphylococcal Arthritis: A Focus On Il-6, Ali Jabbar Abd Al-Hussain Alkawaz, Maryam Sabah Naser, Ali Jalil Obaid, Zakaria M. Al-Ghazaly Jun 2025

Vitamin D3 Toxicity-Induced Hypercalcemia In Staphylococcal Arthritis: A Focus On Il-6, Ali Jabbar Abd Al-Hussain Alkawaz, Maryam Sabah Naser, Ali Jalil Obaid, Zakaria M. Al-Ghazaly

Karbala International Journal of Modern Science

Background: Vitamin D3  over-supplementation can induce toxicity through the development of hypercalcemia and may disturb immune modulation. This study examines the relationship between hypercalcemia  resulting from Vitamin D3 Overdose and serum Interleukin-6 (IL-6) levels in patients diagnosed with staphylococcal arthritis.

Methods: Forty male patients (mean age: 31 years; range: 17–45 years) were enrolled from Dec. 2024 to Feb. 2025. Twenty cases of staphylococcal arthritis were compared with twenty healthy male controls. Serum concentrations of Vitamin D3, calcium, IL-6, and other biochemical markers (urea, creatinine, ESR, WBC, and potassium) were analyzed. Staphylococcus aureus was isolated from synovial fluid and confirmed using …


Vacuum Consistent Electrochemistry In Ionic Liquid Combined With Oxide Epitaxy, Yuji Matsumoto Jun 2025

Vacuum Consistent Electrochemistry In Ionic Liquid Combined With Oxide Epitaxy, Yuji Matsumoto

Journal of Electrochemistry

We introduce our state-of-the art of “vacuum consistent electrochemistry” to an investigation of the interfaces between oxides and ionic liquid (IL). Pulsed laser deposition (PLD) has been one of the powerful and sophisticated techniques to realize nanoscale preparation of high-quality epitaxial oxide thin films. On the other hand, electrochemistry is a simple, very sensitive, and non-destructive analysis technique for solid-liquid interfaces. To ensure the reproducibility in experiment of the interfaces of such epitaxial oxide films, as well as bulk oxide single-crystals, with IL, we employ a home-built PLD-electrochemical (EC) system with IL as an electrolyte. The system allows one to …


A Battle Of Armies: Massive Attack Of Natural Enemies To The True Armyworm Mythimna Unipuncta (Haworth, 1809) (Lepidoptera: Noctuidae) In Forage Crops, Armando Falcon-Brindis, Raul T. Villanueva Jun 2025

A Battle Of Armies: Massive Attack Of Natural Enemies To The True Armyworm Mythimna Unipuncta (Haworth, 1809) (Lepidoptera: Noctuidae) In Forage Crops, Armando Falcon-Brindis, Raul T. Villanueva

Insecta Mundi

Understanding the interactions between plant-host-parasitoid plays a major role in insect pest management. Farmers in the southeastern United States rely on pasture systems for cattle milk and beef production, but the benefits of parasitoids and predators on major lepidopteran pests on pasture lands are still overlooked. Here, we aimed to identify and quantify the effect of parasitism on the true armyworm Mythimna unipuncta (Haworth, 1809) (Lepidoptera: Noctuidae) attacking teff grass Eragrostis tef (Zucc.) Trotter (Poaceae) and crabgrass Digitaria sanguinalis (L.) Scop. (Poaceae) in western Kentucky. In early August of 2023, 547 larvae of M. unipuncta were collected from experimental …


Chemical And Physical Characterization Of Verbenaceae Essential Oils Using Modern Analytical Methods And Chemometrics, Aleksandra N. Hilliard Jun 2025

Chemical And Physical Characterization Of Verbenaceae Essential Oils Using Modern Analytical Methods And Chemometrics, Aleksandra N. Hilliard

Master's Theses

Essential oils have been used for generations to treat various health issues, including mitigating insomnia, reducing stress, inflammation, and preserving foods, to mention a few. Essential oils have complex chemistry, which defines the essence of the host plant. Recently, increased commercial uses of essential oils have prompted attention at the governmental level to monitor the chemical, physical, or biological activity of essential oils. This study is an attempt to add new information for consumers to the understanding of the composition of essential oils.

Modern analytical techniques including FTIR-ATR, GC-MS, LC-MS-MS, multivariate analysis statistics, and physio-chemical techniques (electrochemistry, DPPH, TRC, and …


Potent Acridone Antimalarial Against All Three Life Stages Of Plasmodium, Papireddy Kancharla, Rozalia A. Dodean, Yuexin Li, Xiaowei Zhang, Sean Kelly, Jordan Charlton, Angley Binauhan, Laurize Garcia, Diana Caridha, Jane X. Kelly, Multiple Additional Authors Jun 2025

Potent Acridone Antimalarial Against All Three Life Stages Of Plasmodium, Papireddy Kancharla, Rozalia A. Dodean, Yuexin Li, Xiaowei Zhang, Sean Kelly, Jordan Charlton, Angley Binauhan, Laurize Garcia, Diana Caridha, Jane X. Kelly, Multiple Additional Authors

Chemistry Faculty Publications and Presentations

New antimalarial therapeutics ideally should target all three major life cycle stages. Here we present an acridone antimalarial chemotype that is potent against blood, liver, and mosquito stages of malaria parasites, with the potential for single-dose cure of bloodstream infections, radical cure of liver infections, and blocking of transmission to mosquitoes. Attributes of lead candidate T111 include potent in vitro activity against cultured parasites, ex vivo activity against clinical isolates, oral single dose cure in an asexual blood stage rodent model, inhibition of sexual blood stage parasites, activity against relapsing parasites in non-human primate liver cells, prevention of parasite development …


The Synthesis Of A Photo-Affinity Probe Library For The Fatty Acid Amide Proteome And The Endocannabinoid System Within, Robert E. Feeney Iii Jun 2025

The Synthesis Of A Photo-Affinity Probe Library For The Fatty Acid Amide Proteome And The Endocannabinoid System Within, Robert E. Feeney Iii

USF Tampa Graduate Theses and Dissertations

Fatty acid amides are a large family of endogenous metabolites with significant biological activity, including that of the endocannabinoid system. Currently little is known about how this system of tightly regulated compounds works within humans. This work lays the foundation to explore the structure-activity relationship driving the selectivity of ligand-protein interactions involved with fatty acid amides. A library of activity-based proteomic profiling probes for fatty acid amides has been synthesized to this end. Additionally, progress towards phytocannabinoid probes has been made as well.


The Dynamics Of Daily Area And Depth Of Grazing And Herbage Intake Of Cows In A Five Day Paddock System, M H. Wade, J L. Peyraud, G Lemaire, E A. Comeron Jun 2025

The Dynamics Of Daily Area And Depth Of Grazing And Herbage Intake Of Cows In A Five Day Paddock System, M H. Wade, J L. Peyraud, G Lemaire, E A. Comeron

IGC Proceedings (1977-2023)

Optimisation of animal production per unit area results in a penalty to individual animal production and herbage intake. The objective of the present study was to examine the dynamic changes in a grass sward in relation to declining production and herbage intake in five day paddocks grazed by dairy cows. The study formed part of a larger project to examine the effects of stocking rate and grazing method upon milk production and herbage intake that is reported by Peyraud et al. (1989).


The Relationship Of Herbage Intake Of Cattle To Herbage Mass, And Its Utilization On Rotationally Grazed Pasture, T Okajima, K Sawada, H Noriike, H Yokota Jun 2025

The Relationship Of Herbage Intake Of Cattle To Herbage Mass, And Its Utilization On Rotationally Grazed Pasture, T Okajima, K Sawada, H Noriike, H Yokota

IGC Proceedings (1977-2023)

In the central part of Honshu island in Japan, seasonal vari­ation of herbage mass is also large (Okajima et al., 1985). So, when the grazing managements, i.e. stocking rate, grazing intensity etc., were not appropriate, part of herbage produced was lost through standing dead and litter, or grazing cattle lose their body weight. Sward characteristics affect the grazing behaviour of cattle (Jamieson and Hodgson, 1979), and then affect the herbage production and utilization. Relative herbage intake of cows was related to sward height (Baker et al., 1981). So, sward height was used as the indicator of the grazing management in …


The Effect Of Daily Herbage Allowance On The Ingestive Behavior Of Dairy Cows, M Rogalski, J Kryszak, Z Karzoun Jun 2025

The Effect Of Daily Herbage Allowance On The Ingestive Behavior Of Dairy Cows, M Rogalski, J Kryszak, Z Karzoun

IGC Proceedings (1977-2023)

In conditions of pasture feeding sward selection and con­sumption by grazing animals is strongly influenced by char­acters of herbage (Forbes, 1986). Quantitative and qualitative state of the sward affects its consumption primarily through changes of such elements in animal behaviour as grazing time and number and size of bites (Hodgson, 1982, 1985). Rela­tivelyt much research has been done to investigate the response to the grazed sward of such ruminants as sheep, while the response of cattle, and particularly of dairy cows, has received much less attention (Arnold, 1981 ; Holmes, 1980). This paper presents results of investigations on the effect …


Effect Of Grazing On Pasture Production In South-West Western Australia, K.M S. Curtis, A C. Dunlop, T O. Albertson Jun 2025

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 …


Development Of A General Relationship Between Stocking Rate And Animal Production, J.M Van Heerden, N M. Tainton Jun 2025

Development Of A General Relationship Between Stocking Rate And Animal Production, J.M Van Heerden, N M. Tainton

IGC Proceedings (1977-2023)

One of the best known mathematical representations of the relationship between stocking rate and individual animal pro­duction, that of Mot (1960), postulated a modified exponential relationship. Subsequent workers, however, derived a linear relationship between stocking rate and production per animal unit, at least at stocking rates beyond a certain minimum value. One of these relationships, that of Jones & Sandland (1974), is widely used in South Africa. The results of grazing trials with sheep on complex grass/legume mixtures in the winter rainfall region of South Africa (van Heerden & Tainton, 1987-1988), however, suggested a degree of non-linearity in this relation­ship. …