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University of Arkansas, Fayetteville

2019

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Contrasting And Synthesizing Perspectives On Late Stage Capitalism And The French Revolution, Alyssa Allen Dec 2019

Contrasting And Synthesizing Perspectives On Late Stage Capitalism And The French Revolution, Alyssa Allen

Jessie O'Kelly Freshman Essay Award

The modern-day American wealth inequality epidemic coupled with the effective silencing of the masses through superdelegates and the Electoral College fosters conditions akin to Pre-Revolutionary France with the bourgeoisie being oppressed through wealth inequality and the Estate System.


Understanding How The Effectors Hopd1 And Hopg1 From The Bacterial Pathogen Pseudomonas Syringae Pv. Tomato Dc3000 Target The Arabidopsis Thaliana Protein Atnhr2b To Cause Disease In Plants, Catalina Maria Rodriguez Puerto Dec 2019

Understanding How The Effectors Hopd1 And Hopg1 From The Bacterial Pathogen Pseudomonas Syringae Pv. Tomato Dc3000 Target The Arabidopsis Thaliana Protein Atnhr2b To Cause Disease In Plants, Catalina Maria Rodriguez Puerto

Graduate Theses and Dissertations

The pathogenicity of Pseudomonas syringae is associated with the type III secretion system (T3SS), a complex of proteins assembled in the inner and outer bacterial membranes that traverses the plant cell wall to deliver bacterial proteins into the cytoplasm of plant cells. The effector proteins translocated into the plant cells are called Hops (Hypersensitive response and pathogenicity outer proteins). Bacterial effectors target plant immune proteins to suppress defense responses and enhance bacterial parasitism. The Arabidopsis thaliana nonhost resistance 2B (AtNHR2B), a recently identified immune protein, is degraded after inoculation with the adapted pathogen of Arabidopsis, P. syringae pv tomato DC3000 …


Weigh-In-Motion Auto-Calibration Using Automatic Vehicle Identification, Fu Ren Zhang Zhang Durandal Dec 2019

Weigh-In-Motion Auto-Calibration Using Automatic Vehicle Identification, Fu Ren Zhang Zhang Durandal

Graduate Theses and Dissertations

Weigh-in-Motion (WIM) sensors are installed on mainline lanes at highway locations to record vehicle weights, axle spacing, vehicle class, travel speed, vehicle length, and traffic volume. These data elements support effective transportation planning, infrastructure design, and policy development. Therefore, it is important that WIM sensors supply accurate data. After initial installation and calibration, WIM systems may experience measurement drifts in weight and axle detection. Recalibration takes two general forms: (a) On-site calibration involving running trucks of known weight over WIM scales and (b) Auto-calibration methods involving comparisons to assumed reference weights. Auto-calibration can be more cost and time effective than …


Cytotoxicity And Mutagenicity Of Disinfection Byproduct Mixtures Formulated Using Free Chlorine And Monochloramine, Yonas Ghebremedhin Dec 2019

Cytotoxicity And Mutagenicity Of Disinfection Byproduct Mixtures Formulated Using Free Chlorine And Monochloramine, Yonas Ghebremedhin

Graduate Theses and Dissertations

Bioassays have been used extensively to assess various toxicity endpoints of drinking water disinfection byproducts (DBPs), but an emphasis on single compounds prevails. In this research, DBP mixtures were assessed using a cytotoxicity test with Chinese Hamster Ovary (CHO) cells and an Ames fluctuation test with Salmonella typhimurium TA-98 and TA-100 with and without S9 rat liver homogenate. Seven whole mixture DBP concentrates were formulated using reconstituted natural organic matter (NOM) extracts from the Upper Mississippi River using scaled disinfectant dosing protocols with free chlorine and monochloramine in the presence and absence of added bromide. DBPs were identified by gas …


Evaluation Of Fracture Principles In Asphalt Concrete Utilizing The Sc(B) Geometry, Airam Marlee Morales Vega Dec 2019

Evaluation Of Fracture Principles In Asphalt Concrete Utilizing The Sc(B) Geometry, Airam Marlee Morales Vega

Graduate Theses and Dissertations

Since cracking is one of the principal distresses to be considered in asphalt concrete, multiple fracture tests and geometries have been used to quantify cracking resistance. One of the most popular geometries that have been used in fracture tests is the Semi-Circular bend (SC(B)). However, for this geometry, most of the fracture test methods use different parameters such as thickness, testing temperatures, and loading rates. Thus, the purpose of this research was first to evaluate fracture energy by performing a ruggedness test based on ASTM E1169. Then, to apply fracture mechanics concepts to evaluate three specimen thicknesses (25, 50, and …


(In)Equality., Jongin Choi Dec 2019

(In)Equality., Jongin Choi

Graduate Theses and Dissertations

(in)Equality. centers around my experiences as a transnational person and those around me who have affected my current concept of equality and cultural histories. My visual methodologies cover digital photography and editing, inkjet printing, and laser engraving: multimedia in a process of new discovery, translation between analog and digital, and rearticulation. The exhibition includes portraits peering down from above, illuminated by projected patterns and manipulated messages from Nike’s “Equality.” (2017). The purpose of this thesis paper is to describe the elements of identity, marginalization, and personal reaction to advertising, as well as the and theories which have shaped this project. …


Incorporating Geophysical Data In Slope Stability Modeling For Two Slopes In Arkansas, Vanessa Lebow Dec 2019

Incorporating Geophysical Data In Slope Stability Modeling For Two Slopes In Arkansas, Vanessa Lebow

Graduate Theses and Dissertations

Slope failures in the United States alone cause millions of dollars in damage to infrastructure, threaten national monuments, create environmental hazards, and take an average of 25-50 lives a year. With the inevitable construction that occurs on slopes, it is imperative that the slopes be properly designed which requires a thorough understanding of slope grade, subsurface soil conditions, soil strength parameters, water table locations, and depth to bedrock across the entire site. The preferred method of data collection would be to use borings and other in-situ methods; however, sometimes due to cost constraints or site accessibility only a very limited …


Evaluation Of Concrete Deck Curing Regimens Using Capillary Pressure Sensing System, Samuel Spann Dec 2019

Evaluation Of Concrete Deck Curing Regimens Using Capillary Pressure Sensing System, Samuel Spann

Graduate Theses and Dissertations

Early-age plastic shrinkage cracking is a common problem with the construction of concrete bridge decks due to the high surface area-to-volume ratio and exposure to potentially detrimental environmental effects. Curing regimens are utilized to mitigate cracking risk during the plastic stage of the concrete; the curing regimens evaluated for this study were wet burlap-polyethylene sheeting, two acrylic curing compounds, and one lithium compound. Capillary pressure in the water filled pores has been shown to correlate to the plastic shrinkage cracking risk of concrete. A new portable system has been developed to measure the capillary pressure that could potentially be used …


Truck Activity Pattern Classification Using Anonymous Mobile Sensor Data, Taslima Akter Dec 2019

Truck Activity Pattern Classification Using Anonymous Mobile Sensor Data, Taslima Akter

Graduate Theses and Dissertations

To construct, operate, and maintain a transportation system that supports the efficient movement of freight, transportation agencies must understand economic drivers of freight flow. This is a challenge since freight movement data available to transportation agencies is typically void of commodity and industry information, factors that tie freight movements to underlying economic conditions. With recent advances in the resolution and availability of big data from Global Positioning Systems (GPS), it may be possible to fill this critical freight data gap. However, there is a need for methodological approaches to enable usage of this data for freight planning and operations.

To …


The Effects Of Seed-Applied Fluopyram On Root Penetration And Development Of Meloidogyne Incognita On Cotton And Soybean, Tracy Hawk Dec 2019

The Effects Of Seed-Applied Fluopyram On Root Penetration And Development Of Meloidogyne Incognita On Cotton And Soybean, Tracy Hawk

Graduate Theses and Dissertations

Plant-parasitic nematodes are major pests of cotton and soybean in Arkansas, and across the Southern United States. These nematodes cause more than $3 billion worth of crop losses each year, in part due to lack of available control tactics, such as nematicides. Fluopyram has recently been registered as a seed-treatment nematicide in agronomic crops. The toxicity of fluopyram against Meloidogyne incognita infection has been reported, however, information on root protection provided by fluopyram against Meloidogyne incognita is lacking. The first objective of this research was to evaluate the effect seed-applied fluopyram had on nematode development, root galling, and reproduction on …


Study Of Internal Strains Developed In Concrete Decks At Early Ages In Steel Continuous Bridges, Fernando R. Benitez Ortiz Dec 2019

Study Of Internal Strains Developed In Concrete Decks At Early Ages In Steel Continuous Bridges, Fernando R. Benitez Ortiz

Graduate Theses and Dissertations

The Arkansas Department of Transportation (ARDOT) has identified bridge deck cracking shortly after concrete decks are placed and prior to applying traffic loads. Previous researchers have confirmed improper construction practices and design methods can lead to deck cracking. Currently, many contractors throughout Arkansas are using continuous deck pours. This construction approach may restrict the concrete slab from movement during early age shrinkage, causing tensile stresses to develop. The final stresses at the end of construction must be lower than the concrete tensile strength, if not cracking issues will develop. Eventually, these cracks may enlarge due to service load stresses and …


Use Of Aerial Imagery And Novel Experimental Design To Determine The Distribution Of Foliar Diseases On Soybean And Improve Efficiency Of Product Testing, Mckayla Patterson Dec 2019

Use Of Aerial Imagery And Novel Experimental Design To Determine The Distribution Of Foliar Diseases On Soybean And Improve Efficiency Of Product Testing, Mckayla Patterson

Graduate Theses and Dissertations

Soybeans are grown on approximately 1.3 million ha in Arkansas generating an estimated $1.7 billion annually. Foliar diseases on soybean can result in economic losses. Growers spend significant time and money on disease scouting via crop consultants and often (subsequent) fungicide applications. Fungicide trials are often arranged in small plots designs. In these scenarios, spatial variability of foliar disease is minimized. While it is advantageous to minimize variance outside of treatment differences, another limitation with many small plot trials is ample disease pressure or having only lower severity. Within a commercial production field, soil types and disease severities vary. Logically, …


Extracting Patterns In Medical Claims Data For Predicting Opioid Overdose, Ryan Sanders Dec 2019

Extracting Patterns In Medical Claims Data For Predicting Opioid Overdose, Ryan Sanders

Graduate Theses and Dissertations

The goal of this project is to develop an efficient methodology for extracting features from time-dependent variables in transaction data. Transaction data is collected at varying time intervals making feature extraction more difficult. Unsupervised representational learning techniques are investigated, and the results compared with those from other feature engineering techniques. A successful methodology provides features that improve the accuracy of any machine learning technique. This methodology is then applied to insurance claims data in order to find features to predict whether a patient is at risk of overdosing on opioids. This data covers prescription, inpatient, and outpatient transactions. Features created …


Incorporating Word Order Explicitly In Glove Word Embedding, Brandon Cox Dec 2019

Incorporating Word Order Explicitly In Glove Word Embedding, Brandon Cox

Computer Science and Computer Engineering Undergraduate Honors Theses

Word embedding is the process of representing words from a corpus of text as real number vectors. These vectors are often derived from frequency statistics from the source corpus. In the GloVe model as proposed by Pennington et al., these vectors are generated using a word-word cooccurrence matrix. However, the GloVe model fails to explicitly take into account the order in which words appear within the contexts of other words. In this paper, multiple methods of incorporating word order in GloVe word embeddings are proposed. The most successful method involves directly concatenating several word vector matrices for each position in …


Load Flow Analysis Of 138/69kv Substation Using Electrical Transient & Analysis Program (Etap), Vanessa Abadia Gomez Dec 2019

Load Flow Analysis Of 138/69kv Substation Using Electrical Transient & Analysis Program (Etap), Vanessa Abadia Gomez

Electrical Engineering Undergraduate Honors Theses

This paper examines the load flow analysis of a high-voltage substation using ETAP, and explores options for improving the voltage profile of the system. This study yields critical information about the system, such as the voltage drop at each feeder, the voltage at each bus, as well as real and reactive power losses at the different branches and feeders. In this power flow examination, the system’s performance is evaluated for different operating conditions, so that control measurements can be applied if necessary. The experimental results are used for proposing a plan of using fixed and switched shunt capacitor banks to …


The Impact Of Income On Nutrition. A Case Study Of Northern Mozambique, Hunter Swanigan Dec 2019

The Impact Of Income On Nutrition. A Case Study Of Northern Mozambique, Hunter Swanigan

Agricultural Economics and Agribusiness Undergraduate Honors Theses

In 2017, Mozambique ranked as one of the least-developed countries in the world by measures of health, education, and income, and had one of the lowest GDP per capita at $1,300. With a minimal income, purchasing adequate food to meet recommended levels of nutrients for a healthy diet is difficult, leaving almost half of the country’s population undernourished. This study researched what foods are available during the dry months (hungry season) of May through October in the Nampula province of Mozambique to analyze if it is possible to meet the National Institutes of Health’s recommended levels of nutrients from purchasing …


Surface Modification Of Pvdf Membranes For Treating Produced Waters By Direct Contact Membrane Distillation, Zahra Anari Dec 2019

Surface Modification Of Pvdf Membranes For Treating Produced Waters By Direct Contact Membrane Distillation, Zahra Anari

Graduate Theses and Dissertations

Direct contact membrane distillation is a promising unit operation for treating hydraulic fracturing flow back and produced water. However, while a hydrophobic membrane is essential to prevent the passage of water from the feed to the permeate side, fouling by dissolved organic species can compromise membrane performance and result in wetting of the membrane pores. Here four monomers, hydroxyethylmethacrylate, acrylic acid, 1-vinyl-3-allylimidazolium bromide, and 1-vinyl-3-hexylimidazolium bromide have been grafted from the surface of a PVDF membrane. The modified and base membranes were tested in a direct contact membrane distillation system. All membranes were challenged with real produced water. In addition, …


Determining Water Requirements In Turfgrass Systems, Tyler Quinn Carr Dec 2019

Determining Water Requirements In Turfgrass Systems, Tyler Quinn Carr

Graduate Theses and Dissertations

Turfgrass lawns are commonly utilized for home and commercial applications because of the aesthetic, environmental, and recreational benefits grasses provide, but many people perceive turfgrass as solely an aesthetic benefit that requires significant water inputs. It is important to identify and use turfgrass cultivars that have known drought tolerance, and also fine-tune and throughout development. A series of field experiments were conducted to determine the water requirements of turfgrass lawn systems with the following objectives: 1) investigate differences in chronic drought resistance and irrigation recommendations among cultivars of Kentucky bluegrass (Poa pratensis L.) and tall fescue (Festuca arundinacea Schreb.) 2) …


Optimizing Block-Stacking Operations With Relocation, Hueon Lee Dec 2019

Optimizing Block-Stacking Operations With Relocation, Hueon Lee

Graduate Theses and Dissertations

The focus of the dissertation is developing the optimization problem of finding the minimum-cost operational plan of block stacking with relocation as well as devising a solution procedure to solve practical-sized instances of the problem. Assuming changeable row depth instead of permanent row depth, this research is distinguished from conventional block stacking studies.

The first contribution of the dissertation is the development of the optimization problem under the assumption of deterministic demand. The problem is modeled using integer programming as a variation of the unsplittable multi-commodity flow problem. To find a good feasible solution of practical-sized instances in reasonable time, …


Illuminating Pay Secrecy: Construct Clarification And An Exploration Of Effects Via The Incentive And Sorting Tracks, Sarah Holtzen Dec 2019

Illuminating Pay Secrecy: Construct Clarification And An Exploration Of Effects Via The Incentive And Sorting Tracks, Sarah Holtzen

Graduate Theses and Dissertations

Pay secrecy is a burgeoning debate in compensation research. On one side of the debate, it is argued that pay secrecy is a useful and beneficial practice because it can prevent potential dissatisfaction and destructive competition possible when people make unfavorable pay comparisons. On the other side, it is argued that pay secrecy is undesirable because it obscures the motivational properties of pay and does not prevent people from making pay comparisons, nor safeguard them from the resulting dissatisfaction. Despite the popularity of pay secrecy in organizations today, extant research has failed to provide any definitive answers as to whether …


Genetic Relationships Using Mitochondrial Versus Nuclear Markers: Is The Catfish Rag1 Gene Suitable For Species Differentiation In The Family Pangasiidae?, Huong Thanh Hoang Dec 2019

Genetic Relationships Using Mitochondrial Versus Nuclear Markers: Is The Catfish Rag1 Gene Suitable For Species Differentiation In The Family Pangasiidae?, Huong Thanh Hoang

Graduate Theses and Dissertations

The Mekong River located in Southeast Asia is a global “hotspot” for aquatic biodiversity. It includes an extensive variety of fish species second only to the Amazon River in South America. Recent studies have revealed the impacts of anthropogenic and climate factors on this river system. Such impacts can result in the formation of barriers, which divide a species population and impede gene flow between separated sub-populations. Barriers influence evolutionary trajectories resulting in the generation of geographic variants or subspecies from an ancestral population. Catfish (Teleostei: Siluriformes) are a key species of the Mekong River ecosystem and are an essential …


The Feedback-Related Negativity Is A Time-Dependent Brain Mechanism That Facilitates Aversive Learning: Implications For The Reinforcement Learning Frn Hypothesis, Eric Rawls Dec 2019

The Feedback-Related Negativity Is A Time-Dependent Brain Mechanism That Facilitates Aversive Learning: Implications For The Reinforcement Learning Frn Hypothesis, Eric Rawls

Graduate Theses and Dissertations

Organisms encode rewarding and aversive experiences through reinforcement learning, capitalizing on prediction errors (PEs), which adapt action strategies over time. Computational theories are explicit that PE signals should update action weights continuously over the course of a behavioral task, an important time-dependent variation that is eschewed in traditional neuroscience studies that average over large numbers of trials. I examined variation in reaction times and feedback-locked cortical activity over time as a function of PE to critically examine theories indicating that PE signals drive time-dependent learning. We recorded EEG while participants completed a novel reinforcement task that varied prediction error on …


Observable Persistent Effects Of Habitat Management Efforts In The Ozark Highlands After 10 Years, Maxwell Carnes-Mason Dec 2019

Observable Persistent Effects Of Habitat Management Efforts In The Ozark Highlands After 10 Years, Maxwell Carnes-Mason

Graduate Theses and Dissertations

I investigated the lasting impacts of a management plan designed to improve oak regeneration and benefit wildlife in the Ozark Highlands in Madison, Co., AR. To assess the efficacy of the management plan, I used variables relevant to the success and establishment of oak trees. Controlled burns and selective logging were used to thin the canopy, increase ground level productivity, and increase the abundance of small mammals. I used measurements of overstory and understory densities, light availability, and the density of mice in the genus Peromyscus across time to look at the lasting impacts of management. Different treatment plots were …


Species Richness And Ecological Diversity Of Myxomycetes And Myxomycete-Like Organisms In The Tropical Forests Of Brazil, Isadora Lima Coelho Dec 2019

Species Richness And Ecological Diversity Of Myxomycetes And Myxomycete-Like Organisms In The Tropical Forests Of Brazil, Isadora Lima Coelho

Graduate Theses and Dissertations

Tropical rain forests cover less than two percent of Earth's surface, yet they sustain the greatest diversity of living organisms on the planet. Tropical rain forests cover nearly 73% of the Brazilian territory and besides harboring some of the most biodiverse ecosystems on the planet, this vast area also houses about 83% of the Brazilian population. Approximately 175 million people live in urban and rural areas with fragments of coverage of these biomes which contributes to the loss of biodiversity that rapidly increases over the years. Furthermore, the majority of the taxonomic and ecological efforts to describe and protect the …


Coccidiosis Vaccination And Nutrient Utilization In Broiler Chickens, Alyson Elaine Gautier Dec 2019

Coccidiosis Vaccination And Nutrient Utilization In Broiler Chickens, Alyson Elaine Gautier

Graduate Theses and Dissertations

Four experiments were conducted to evaluate the interrelationships among coccidiosis vaccination and nutrient utilization in floor-reared broiler chickens. Experiment 1 longitudinally compared the effects of coccidiosis vaccination and a chemical coccidiostat on broiler performance, nutrient digestibility, and intestinal morphology. Coccidiosis vaccination had no significant impact on morphology, overall body weight gain and feed intake of vaccinated birds, although vaccination impaired overall FCR. Vaccination elicited a transient reduction in digestibility of energy and nutrients, particularly for lipids, but vaccinated birds were able to recover from these reductions by 20 d. Experiment 2 assessed the impact of vaccination in digestibility of different …


Synthesis Of Cellulose Nanocrystal-Gold Nanoparticle Hybrid System For Surface Plasmon-Enhanced Property, Mahshid Iraniparast Dec 2019

Synthesis Of Cellulose Nanocrystal-Gold Nanoparticle Hybrid System For Surface Plasmon-Enhanced Property, Mahshid Iraniparast

Graduate Theses and Dissertations

Gold nanoparticles (AuNPs) have been brought to the forefront of various applications, ranging from theranostics, to organic photovoltaics, to biosensing owing to their localized surface plasmon resonance (LSPR) property. However, this property needs to be improved in order to allow for high sensitivity and quantitative detection of biomolecules. Hybrids of AuNPs with low-dielectric cellulose nanocrystal (CNCs) would yield enhancement of the LSPR property, which is driven by the confinement of electron oscillation at their interfaces. This study proposed a seed-mediated growth method to synthesize hybrids of CNCs-AuNPs. Sulfate groups on the surface of CNCs served as the sites for the …


A Geospatial Analysis Of Safety And Risk Perception In The Buffalo National River, Julie Nicole Terhune Dec 2019

A Geospatial Analysis Of Safety And Risk Perception In The Buffalo National River, Julie Nicole Terhune

Graduate Theses and Dissertations

In 1972, the Buffalo River in Arkansas became America’s First National River. Since then, the Buffalo National River has become a beloved recreational retreat for locals and visitors alike. The Buffalo National River is home to incredibly scenic views and host to many outdoor activities, among them, hiking and floating. As with any confluence of nature and humans, there is great risk involved in all aspects of the park. Between 2011 and 2017, a total of 140 search and rescue missions were carried out. Some were resolved easily, but more serious accidents were not unheard of.

Risk perception studies are …


Studies Of Initial Growth Of Gan On Inn, Alaa Alnami Dec 2019

Studies Of Initial Growth Of Gan On Inn, Alaa Alnami

Graduate Theses and Dissertations

III-nitride materials have recently attracted much attention for applications in both the microelectronics and optoelectronics. For optoelectronic devices, III-nitride materials with tunable energy band gaps can be used as the active region of devices to enhance the absorption or emission. A such material is indium nitride (InN), which along with gallium nitride (GaN) and aluminum nitride (AlN) embody the very real promise of forming the basis of a broad spectrum, a high efficiency solar cell. One of the remaining complications in incorporating InN into a solar cell design is the effects of the high temperature growth of the GaN crystal …


Global Acetylation Dynamics In The Heat Shock Response Of Saccharomyces Cerevisiae, Rebecca E. Hardman Dec 2019

Global Acetylation Dynamics In The Heat Shock Response Of Saccharomyces Cerevisiae, Rebecca E. Hardman

Graduate Theses and Dissertations

All organisms face a constant barrage of environmental stresses. Single-cell organisms such as Saccharomyces cerevisiae, or common Baker’s yeast, must rely solely on cellular responses in order to survive. This response must occur in a rapid and highly coordinated manner to quickly inhibit all unnecessary processes and shuttle all available resources to those necessary for survival. One method that cells utilize for rapid protein regulation is the use of post-translational modifications. Enzymes within the cell add or remove a variety of chemical modifications, thus altering the local chemical environment of a protein. This creates a conformational change in the protein …


Strategies To Improve Forage Utilization By Sheep Offered Forage Mixtures, Valens Niyigena Dec 2019

Strategies To Improve Forage Utilization By Sheep Offered Forage Mixtures, Valens Niyigena

Graduate Theses and Dissertations

In the first experiment, alfalfa and novel endophyte-infected tall fescue (NE+) forages were harvested after a killing frost, then mixed to formulate 4 different treatments; alfalfa alone, 67% alfalfa +33% fescue, 33% alfalfa + 67% fescue, or 100% fescue. After 3 months of storage as silage, Dorper ewe lambs (n = 20; mean BW = 34.7 ± 6.65 kg) were fed silage for ad libitum consumption, using 5 animals per treatment. Increasing the proportion of NE+ tall fescue improved (P < 0.05) silage total acids and lactic acid concentrations and decreased silage ammonia concentration. Digestible dry matter and organic matter intake and nitrogen utilization parameters decreased with increasing inclusion of NE+ in diet. In the second experiment, 16 Dorper ewe lambs (41.8 ± 4.61 kg BW) were assigned to 4 different treatments; alfalfa silage alone (0 g/kg; CONT) or alfalfa silage mixed with chopped sericea lespedeza (SL) hay to provide 90 (LOW), 180 (MED), or 270 g/kg SL (HIGH) on a dry matter basis in a randomized complete block design experiment with 2 period to provide 4 observations per treatment for each experimental period. Increasing the proportion of sericea lespedeza in the diet decreased dry matter and organic matter digestibility but did not affect feed intake. Fecal nitrogen (g/kg N intake) increased linearly (P < 0.01) while urinary N (g/ day and g/ kg of N intake) tended to decreased linearly and quadratically (P ≤ 0.1) with increasing the proportion of SL in diet. In the third experiments, 16 gestating Dorper ewe lambs (49.1 ± 4.61 kg BW) were allocated to 4 treatments; alfalfa silage alone (0% g/kg; CONT) or alfalfa silage mixed with lablab purpureus(LP) hay to provide 90 (LOW), 180 (MED), or 270 g/kg LP (HIGH) on a dry matter (DM) basis, in a randomized complete block design experiment with a total 8 replication per treatment. Supplementation of LP in diet increased quadratically (P ≤ 0.04) forage dry matter, organic matter intake, digestible dry matter and digestible organic matter intake (P < 0.05). Nitrogen apparently absorbed and urinary N both decreased linearly (P < 0.01) with adding more LP hay in diet. Harvesting and mixing alfalfa and fescue after a killing frost improved silage fermentation characteristics and supplementation of tannins from SL and polyphenol from LP altered N excretion.

Key words: lablab, sericea lespedeza, alfalfa silage, nitrogen, sheep.