Digital Commons Network^™

Spring Calving Suckler Beef Systems: Influence Of Grassland Management System On Herbage Availability, Utilisation, Quality And Cow And Calf Performance To Weaning, M. J. Drennan, M. Mcgee, S. Kyne, B. O'Neill

IGC Proceedings (1977-2023)

Suckler beef systems in Ireland are primarily based on grass. Suckler systems vary in intensity but many operate low input systems and participate in REPS (Rural Environmental Protection Scheme). As there is a considerable cost associated with second-cut silage this research compared a two-cut system with a simplified low input one-cut system.

The Importance Of Patch Size In Estimating Steady-State Bite Rate In Grazing Cattle, E. D. Ungar, N. Ravid, T. Zada, E. Ben-Moshe, R. Yonatan, S. Brenner, H. Baram, A. Genizi

IGC Proceedings (1977-2023)

Since the pioneering work of Black and Kenney (1984), various intake studies have been conducted at the spatial scale of a single feeding station ("patch") to elucidate the processes that determine instantaneous intake rate (e.g. Laca et al., 1994). While these are well-suited for patch depletion studies, it is less clear how well they represent non-patchy and relatively homogeneous environments (Ungar & Griffiths, 2002). Clearly, grazing should be restricted to the upper grazing horizon (i.e. layer of bites), but sample duration may be insufficient to characterize steady-state behaviour, especially when grazing commences on an empty mouth. We examined the …

Performance Of Meat Goats Grazing Winter Annual Grasses In The Piedmont Of The Southeastern Usa, J-M. Luginbuhl, J. P. Mueller

IGC Proceedings (1977-2023)

In the Southeastern United States, meat goats (Capra hircus hircus) are becoming increasingly important contributors to the income of many small producers. Meat goats perform well in grazing situations if grazing management practices match their grazing behavior. Nevertheless, little research data are available from the region specifically directed toward forage feeding programs for goats reared for meat production. Hart et al. (1993) reported that growing Alpine, Angora and Nubian kids grazed on high quality Triticum aestivum forage gained 50 g/d, whereas Kiesling et al. (1994) reported gains ranging from 65 to 141 g/d in growing Angora …

The Effect Of Early And Delayed Spring Grazing On The Milk Production, Grazing Management And Grass Intake Of Dairy Cows, E. Kennedy, M. O'Donovan, J. P. Murphy, L. Delaby, F. P. O'Mara

IGC Proceedings (1977-2023)

Earlier access to pasture can increase the overall proportion of grazed grass in the diet of the spring calving dairy cow. Further benefits can also be achieved from early turnout, including improved animal production, increased sward utilisation and enhanced sward quality (O’Donovan et al., 2004). The objective of this study was to compare the effect of initial spring grazing date and stocking rate on the performance of spring calving dairy cows.

Intake Characteristics Of Diploid And Tetraploid Perennial Ryegrass Varieties When Grazed By Simmental X Holstein Yearling Heifers Under Rotational Stocking Management, R. J. Orr, J. E. Cook, K. L. Young, R. A. Champion, A. J. Rook

IGC Proceedings (1977-2023)

Orr et al. (2003) measured large differences in dry matter (DM) intake rate between 15 intermediate-heading perennial ryegrass varieties when they were continuously stocked with sheep and subsequently explored the extent to which, for 5 of these varieties, these differences could be explained by chemical and morphological traits (Orr et al., 2004a) which could be targeted in grass breeding programmes. Here, four of the 15 varieties, which within ploidy had low or high intake characteristics when grazed by sheep, were rotationally stocked with cattle and intake and sward factors were measured.

Optimising Financial Return From Grazing In Temperate Pastures, P. Dillon, J. R. Roche, L. Shalloo, B. Horan

IGC Proceedings (1977-2023)

Key Points

1. The increased interest in pasture-based systems of milk production in recent years has been largely generated through lower product prices and rising costs of production.

2. Pasture based systems of milk production decrease unit production costs, through lower feed and labour expenses, and reduced capital investment.

3. Systems utilising grazed pasture will be optimised in regions where pasture production potential is high, variability in seasonal pasture supply and quality is low, manufacturing milk accounts for a large proportion of total production, and where large areas of land are available at relatively low cost.

4. Pasture based systems may allow greater global …

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Challenges And Opportunities For Animal Production From Temperate Pastures, D. A. Clark

IGC Proceedings (1977-2023)

Key points

1. Temperate pastures offer a major opportunity to reduce the feed costs associated with ruminant production.

2. Pastures offer unique opportunities for producing high value components in feedstuffs that are beneficial to human health.

3. The increased use of pasture will not automatically lead to improved environmental outcomes – difficult challenges exist in reducing nitrogen and greenhouse gas pollution.

4. Grazed pasture systems offer advantages in animal welfare, provided management avoids the problems associated with climatic extremes, and the toxins associated with some pastures.

5. To remain competitive with total mixed ration systems, and environmentally acceptable, pastures with higher intake characteristics that allow …

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Decision Support For Temperate Grasslands: Challenges And Pitfalls, J. R. Donnelly, L. Salmon, R. D. H. Cohen, Zl. Liu, Xp. Xin

IGC Proceedings (1977-2023)

Key points

1. Successful adoption of decision support tools (DS tools) to address grassland management issues requires careful attention in design to ensure ease-of-use, accuracy in prediction and the flexibility to simulate actual practices.

2. DS tools must handle spatial variability and where possible include facilities for automatic sourcing of essential information for initialisation.

3. Advances in the development of DS tools will depend on resolution of scientific issues in grassland biology including investment in dedicated experiments to determine parameter values for model equations.

4. The use of mechanistic models, the integration of remote sensing technology and cooperation between research groups to develop modular …

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Modelling Of Herbage Intake And Milk Production By Grazing Dairy Cows, Rémy Delagarde, M. O'Donovan

IGC Proceedings (1977-2023)

Key-points

1. Models predicting intake and performance of grazing ruminants from animal, sward, grazing and supplements characteristics are rare, but they are now included in several decision support systems (DSS).

2. An evaluation of the performance and accuracy of published models are rarely undertaken by their authors, but this is proposed in this paper.

3. There is still a need for experimental research but also for the development of generic and dynamic models to predict intake and performance over a wide range of grazing conditions.

Grass Growth Modelling: To Increase Understanding And Aid Decision Making On-Farm, P. D. Barrett, A. S. Laidlaw

IGC Proceedings (1977-2023)

Key points

1. Crop and grass growth models have been developed over the last 50 years, or so, but general appreciation of their benefits and potential has been recognised only relatively recently. The most popular application of grass growth models has traditionally been for knowledge understanding.

2. There is growing awareness of the potential of models in decision support systems (DSS) applications to aid pasture management and grassland budgeting on dairy farms.

3. Although some models have been developed for DSS, their widespread uptake in industry has been slow; challenges still exist which need to be addressed in order to improve their precision …

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Genetic Characteristics Required In Dairy And Beef Cattle For Temperate Grazing Systems, F. Buckley, C. Holmes, M. G. Keane

IGC Proceedings (1977-2023)

Key points

1. Only about 10% of the world’s milk is produced from grazing systems. Consequently the majority of dairy cattle have not been selected under grazing, nor on seasonal systems. This is not true for beef cattle, for which the majority, especially the dams, are managed under seasonal grazing systems.

2. In grazing systems daily feed intake is limited to lower levels than are achievable on concentrate plus conserved forage rations. Consequently, cows most suited to grazing environments are likely to have a lower genetic potential for milk production than cows selected in high concentrate systems, to minimise their relative energy …

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New Insights Into The Nutritional Value Of Grass, D. H. Rearte

IGC Proceedings (1977-2023)

Key points

1. The rumen environment in cattle grazing high quality forage is different to that reported for cattle fed indoors with diets based on processed feedstuffs.
2. Temperate pasture is an excellent source of nutrients for ruminants but a high energy:protein imbalance can occur when it is offered at the stage of optimal digestion.
3. Beef and milk produced on grass in temperate regions have a composition with nutritional advantages over beef or milk produced in indoor systems based on concentrate.
4. Increasing water soluble carbohydrate content of grasses would diminish environmental contamination by reducing the excretion of urea through the urine.
5. Increasing …

Plant And Sward Characteristics To Achieve High Intake In Ruminants, W. J. Wales, C. R. Stockdale, P. T. Doyle

IGC Proceedings (1977-2023)

Key points

1. Intake is affected by complex interactions between signals from the digestive tract, intermediary metabolism and energy supply, and behavioural signals associated with learned behaviours or sensory signals.
2. The ideal sward needs to have characteristics that are similar to total mixed rations to achieve high intake and animal performance.
3. Genetic manipulation of plants may offer an accelerated rate of plant improvement, but benefits need to be demonstrated in a systems context.

Overview Of Animal Production From Pastures In Ireland, M. J. Drennan, A. F. Carson, S. Crosse

IGC Proceedings (1977-2023)

Key points

The importance of grassland to agriculture in Ireland is indicated by the fact that:

1. Sixty percent of agricultural output is from grassland as cattle, milk and sheep products.
2. Over 90% of the total farmed area is in grass.
3. Livestock are almost entirely dependent on grazed grass for 200 to 235 days of the year.
4. Grass conserved as silage is the main source of fodder in winter.
5. To improve competitiveness changes are continuously taking place, which include:

• increased suckler herd size and a movement to late maturing continental cattle breeds;
• movement in the dairy herd towards Holstein with increased …

The Archives And You: Why Your Memorabilia Matters, Ruth E. Bryan

Library Presentations

Join Ruth E. Bryan, University Archivist at the University of Kentucky Libraries Special Collections Research Center, as she describes what archives are and how your memorabilia can contribute to historical research and scholarship.

Kentucky Annual Economic Report 2023, Michael Childress, Michael W. Clark, James P. Ziliak, Simon Sheather

Kentucky Annual Economic Report

This report is one of the important ways that the Center for Business and Economic Research fulfills its mission to examine various aspects of Kentucky’s economy as directed by the Kentucky Revised Statutes (KRS 164.738). The analysis and data presented here cover a variety of topics that range from a discussion of Kentucky’s current economic climate to a broad presentation of factors affecting the economy.

Higher Concentrations Of Microplastics In Runoff From Biosolid-Amended Croplands Than Manure-Amended Croplands, Nasrin Naderi Beni, Shahab Karimifard, John Gilley, Tiffany L. Messer, Amy Schmidt, Shannon Bartelt-Hunt

UK CARES Faculty Publications

Land-applied municipal biosolids, produced from municipal wastewater treatment sludge, contributes to microplastics contamination in agroecosystems. The impacts of biosolids on microplastic concentrations in agricultural soil have been previously investigated, however, the potential for microplastics transport from biosolid-amended croplands has not been previously quantified. In this study, manure and biosolids were applied to field plots, runoff was collected following natural precipitation events and the potential of bacterial biofilm to grow on different microplastic morphologies was investigated. Higher concentrations of microplastics were detected in runoff from plots with land-applied biosolid in comparison with manure-amended and control plots. Fibers and fragments were the …

Forage News [2023-02], Department Of Plant And Soil Sciences, University Of Kentucky

Forage News

No abstract provided.

Novel Smad3 Variant Identified In A Patient With Familial Aortopathy Modeled Using A Zebrafish Embryo Assay, Mary Burchett Sheppard, Jeffrey D. Smith, Lisa L. Bergmann, Jakub Konrad Famulski

Saha Cardiovascular Research Center Faculty Publications

In human, pathogenic variants in smad3 are one cause of familial aortopathy. We describe a novel SMAD3 variant of unknown significance (VUS), V244F, in a patient who presented with aortic root dilation, right coronary artery ectasia, abdominal aortic aneurysm, right vertebral artery atresia, and cavernoma. Determination of variant pathogenicity impacted multiple aspects of the patient’s care, including the most appropriate surgical threshold for which to recommend a valve-sparing aortic root replacement. To determine whether the newly identified SMAD3 variant, and whether SMAD3 induced aortopathy in general, can be assayed in a zebrafish embryo model, we injected smad3a mRNA into Tg[kdrl:mCherry] …

Aortic Stress Activates An Adaptive Program In Thoracic Aortic Smooth Muscle Cells That Maintains Aortic Strength And Protects Against Aneurysm And Dissection In Mice, Chen Zhang, Yanming Li, Abhijit Chakraborty, Yang Li, Kimberly R. Rebello, Pingping Ren, Wei Luo, Lin Zhang, Hong S. Lu, Lisa A. Cassis, Joseph S. Coselli, Alan Daugherty, Scott A. Lemaire, Ying H. Shen

Saha Cardiovascular Research Center Faculty Publications

BACKGROUND: When aortic cells are under stress, such as increased hemodynamic pressure, they adapt to the environment by modifying their functions, allowing the aorta to maintain its strength. To understand the regulation of this adaptive response, we examined transcriptomic and epigenomic programs in aortic smooth muscle cells (SMCs) during the adaptive response to AngII (angiotensin II) infusion and determined its importance in protecting against aortic aneurysm and dissection (AAD).

METHODS: We performed single-cell RNA sequencing and single-cell sequencing assay for transposase-accessible chromatin (scATAC-seq) analyses in a mouse model of sporadic AAD induced by AngII infusion. We also examined the direct …

2022 Kentucky River Watershed Watch Annual Report, Steven J. Evans, Malissa Mcalister

Kentucky River Watershed Watch

No abstract provided.

Gasdermin D Deficiency In Vascular Smooth Muscle Cells Ameliorates Abdominal Aortic Aneurysm Through Reducing Putrescine Synthesis, Jianing Gao, Yanghui Chen, Huiqing Wang, Xin Li, Ke Li, Yangkai Xu, Xianwei Xie, Yansong Guo, Nana Yang, Xinhua Zhang, Dong Ma, Hong S. Lu, Ying H. Shen, Yong Liu, Jifeng Zhang, Y. Eugene Chen, Alan Daugherty, Dao Wen Wang, Lemin Zheng

Saha Cardiovascular Research Center Faculty Publications

Abdominal aortic aneurysm (AAA) is a common vascular disease associated with significant phenotypic alterations in vascular smooth muscle cells (VSMCs). Gasdermin D (GSDMD) is a pore-forming effector of pyroptosis. In this study, the role of VSMC-specific GSDMD in the phenotypic alteration of VSMCs and AAA formation is determined. Single-cell transcriptome analyses reveal Gsdmd upregulation in aortic VSMCs in angiotensin (Ang) II-induced AAA. VSMC-specific Gsdmd deletion ameliorates Ang II-induced AAA in apolipoprotein E (ApoE)−/− mice. Using untargeted metabolomic analysis, it is found that putrescine is significantly reduced in the plasma and aortic tissues of VSMC-specific GSDMD deficient mice. High putrescine levels …

The Mechanism And Therapy Of Aortic Aneurysms, Jianing Gao, Huanhuan Cao, Gaofei Hu, Yufei Wu, Yangkai Xu, Hongtu Cui, Hong S. Lu, Lemin Zheng

Saha Cardiovascular Research Center Faculty Publications

Aortic aneurysm is a chronic aortic disease affected by many factors. Although it is generally asymptomatic, it poses a significant threat to human life due to a high risk of rupture. Because of its strong concealment, it is difficult to diagnose the disease in the early stage. At present, there are no effective drugs for the treatment of aneurysms. Surgical intervention and endovascular treatment are the only therapies. Although current studies have discovered that inflammatory responses as well as the production and activation of various proteases promote aortic aneurysm, the specific mechanisms remain unclear. Researchers are further exploring the pathogenesis …

Abl1/2 And Ddr1 Drive Meki Resistance In Nras-Mutant Melanomas By Stabilizing Raf/Myc/Ets1 And Promoting Raf Homodimerization, Anastasia Lyon, Rakshamani Tripathi, Christina Meeks, Daheng He, Yuanyuan Wu, Jinpeng Liu, Chi Wang, Jing Chen, Haining Zhu, Sujata Mukherjee, Saptadwipa Ganguly, Rina Plattner

Markey Cancer Center Faculty Publications

Melanomas harboring NRAS mutations are a particularly aggressive and deadly subtype. If patients cannot tolerate or the melanomas are insensitive to immune checkpoint blockade, there are no effective 2nd-line treatment options. Drugs targeting the RAF/MEK/ERK pathway, which are used for BRAF-mutant melanomas, do little to increase progression-free survival (PFS). Here, using both loss-of-function and gain-of-function approaches, we show that ABL1/2 and DDR1 are critical nodes during NRAS-mutant melanoma intrinsic and acquired MEK inhibitor (MEKi) resistance. In some acquired resistance cells, ABL1/2 and DDR1 cooperate to stabilize RAF proteins, activate ERK cytoplasmic and nuclear signaling, repress p27/KIP1 expression, and drive RAF …

Adolescent- And Adult-Initiated Alcohol Exposure In Mice Differentially Promotes Tumorigenesis And Metastasis Of Breast Cancer, Mei Xu, Hui Li, Danlei Chen, Huaxun Wu, Wen Wen, Hong Xu, Jacqueline Frank, Gang Chen, Jia Luo

Markey Cancer Center Faculty Publications

Background: Alcohol exposure increases the risk of breast cancer. Alcohol consumption by adolescents is a serious social and public health issue. This study investigated the impact of adolescent alcohol consumption on mammary tumorigenesis and progression and compared it to that of adult alcohol exposure in animal models. Methods: Female adolescent (5 weeks) and adult (8 weeks) MMTV-Wnt1 mice were exposed to alcohol either chronically or acutely. For chronic alcohol exposure, animals were fed a liquid diet containing 6.7% ethanol for 23 weeks. For acute exposure, animals were treated with ethanol (2.5 g/kg, 25% w/v) via intraperitoneal (IP) injection for 15 …

Bilirubin Nanoparticle Treatment In Obese Mice Inhibits Hepatic Ceramide Production And Remodels Liver Fat Content, Zachary A. Kipp, Genesee J. Martinez, Evelyn A. Bates, Agil B. Maharramov, Robert M. Flight, Hunter N. B. Moseley, Andrew J. Morris, David E. Stec, Terry D. Hinds Jr.

Markey Cancer Center Faculty Publications

Studies have indicated that increasing plasma bilirubin levels might be useful for preventing and treating hepatic lipid accumulation that occurs with metabolic diseases such as obesity and diabetes. We have previously demonstrated that mice with hyperbilirubinemia had significantly less lipid accumulation in a diet-induced non-alcoholic fatty liver disease (NAFLD) model. However, bilirubin’s effects on individual lipid species are currently unknown. Therefore, we used liquid chromatography-mass spectroscopy (LC-MS) to determine the hepatic lipid composition of obese mice with NAFLD treated with bilirubin nanoparticles or vehicle control. We placed the mice on a high-fat diet (HFD) for 24 weeks and then treated …

Critical Role Of The Sulfiredoxin-Peroxiredoxin Iv Axis In Urethane-Induced Non-Small Cell Lung Cancer, Yanning Hao, Hong Jiang, Pratik Thapa, Na Ding, Aziza Alshahrani, Junichi Fujii, Michel B. Toledano, Qiou Wei

Markey Cancer Center Faculty Publications

Non-small cell lung cancer (NSCLC), the most common type of lung cancer, etiologically associates with tobacco smoking which mechanistically contributes to oxidative stress to facilitate the occurrence of mutations, oncogenic transformation and aberrantly activated signaling pathways. Our previous reports suggested an essential role of Sulfiredoxin (Srx) in promoting the development of lung cancer in humans, and was causally related to Peroxiredoxin IV (Prx4), the major downstream substrate and mediator of Srx-enhanced signaling. To further explore the role of the Srx-Prx4 axis in de novo lung tumorigenesis, we established Prx4−/− and Srx−/−/Prx4−/− mice in pure FVB/N background. Together with wild-type litter …

Ifn-Γ Production By Brain-Resident Cells Activates Cerebral Mrna Expression Of A Wide Spectrum Of Molecules Critical For Both Innate And T Cell-Mediated Protective Immunity To Control Reactivation Of Chronic Infection With Toxoplasma Gondii, Yasuhiro Suzuki, Jenny Lutshumba, Kuey Chu Chen, Mohamed H. Abdelaziz, Qila Sa, Eri Ochiai

Markey Cancer Center Faculty Publications

We previously demonstrated that brain-resident cells produce IFN-g in response to reactivation of cerebral infection with Toxoplasma gondii. To obtain an overall landscape view of the effects of IFN-g from brain-resident cells on the cerebral protective immunity, in the present study we employed NanoString nCounter assay and quantified mRNA levels for 734 genes in myeloid immunity in the brains of T and B cell-deficient, bone marrow chimeric mice with and without IFN-g production by brain-resident cells in response to reactivation of cerebral T. gondii infection. Our study revealed that IFN-g produced by brain-resident cells amplified mRNA expression for the molecules …

Production And Characterization Of Monoclonal Antibodies To Xenopus Proteins, Brett Horr, Ryan Kurtz, Ankit Pandey, Benjamin G. Hoffstrom, Elizabeth Schock, Carole Labonne, Dominique Alfandari

Markey Cancer Center Faculty Publications

Monoclonal antibodies are powerful and versatile tools that enable the study of proteins in diverse contexts. They are often utilized to assist with identification of subcellular localization and characterization of the function of target proteins of interest. However, because there can be considerable sequence diversity between orthologous proteins in Xenopus and mammals, antibodies produced against mouse or human proteins often do not recognize Xenopus counterparts. To address this issue, we refined existing mouse monoclonal antibody production protocols to generate antibodies against Xenopus proteins of interest. Here, we describe several approaches for the generation of useful mouse anti-Xenopus antibodies to multiple …

Grassland Productivity And Water Quality: A 21st Century Issue, David M. Nash, P. M. Haygarth

IGC Proceedings (1977-2023)

1. Irrigation and other changes to the hydrological cycle can increase soil and water salinity.
2. Primary salinisation is a natural process that affects much of Europe, Asia, Africa, the Americas and Australia. Secondary salinisation is caused by human activities such as irrigation and land clearing that mobilise salt stored in the soil.
3. The critical water contaminants exported from grasslands are nitrogen, phosphorus, potential pathogens and sediment.
4. The mechanisms responsible for diffuse pollution from grasslands and mitigation strategies are most effectively investigated using a ‘source-mobilisation-transport’ framework.
5. There is a lack of coherent interaction across discipline boundaries that links pollutant sources to impact. …