Digital Commons Network^™

Mechanical Stresses Associated With Flattening Of Human Femoropopliteal Artery Specimens During Planar Biaxial Testing And Their Effects On The Calculated Physiologic Stress-Stretch State, Majid Jadidi, Anastasia Desyatova, Jason N. Mactaggart, Alexey Kamenskiy

Department of Mechanical and Materials Engineering: Faculty Publications

Planar biaxial testing is commonly used to characterize the mechanical properties of arteries, but stresses associated with specimen flattening during this test are unknown. We quantified flattening effects in human femoropopliteal arteries (FPAs) of different ages, and determined how they affect the calculated arterial physiologic stress-stretch state. Human FPAs from 472 tissue donors (age 12-82 years, mean 53±16 years) were tested using planar biaxial extension, and morphometric and mechanical characteristics were used to assess the flattening effects. Constitutive parameters for the invariant-based model were adjusted to account for specimen flattening, and used to calculate the physiologic stresses, stretches, axial force, …

Born To Take Risk? The Effect Of Ceo Birth Order On Strategic Risk Taking, Robert J. Campbell, Seung-Hwan Jeong, Scott D. Graffin

Department of Management: Faculty Publications

The importance of birth order has been the subject of debate for centuries, and has captured the attention of the general public and researchers alike. Despite this interest, scholars have little understanding of the impact birth order has on CEOs and their strategic decisions. With this in mind, we develop theory that explains how CEO birth order may be associated with strategic risk taking. Drawing from evolutionary theory arguments related to birth order,we theorize that CEO birth order is positively associatedwith strategic risk taking; that is, earlier-born CEOswill take less risk than later-born CEOs. As evolutionary theory proposes that birth …

A Small Viral Potassium Ion Channel With An Inherent Inward Rectification, Denise Eckert, Tobias Schulze, Julian Stahl, Oliver Rauh, James L. Van Etten, Brigitte Hertel, Indra Schroeder, Anna Moroni, Gerhard Thiel

Department of Plant Pathology: Faculty Publications

Some algal viruses have coding sequences for proteins with structural and functional characteristics of pore modules of complex K⁺ channels. Here we exploit the structural diversity among these channel orthologs to discover new basic principles of structure/function correlates in K⁺ channels. The analysis of three similar K⁺ channels with ≤ 86 amino acids (AA) shows that one channel (Kmp_v1) generates an ohmic conductance in HEK293 cells while the other two (Kmpv_SP1, Kmpv_PL1) exhibit typical features of canonical Kir channels. Like Kir channels, the rectification of the viral channels is a function …

Cryopreservation Of Paramecium Bursaria Chlorella Virus-1 During An Active Infection Cycle Of Its Host, Samantha R. Coy, Alyssa N. Alsante, James L. Van Etten, Steven W. Wilhelm

Department of Plant Pathology: Faculty Publications

Best practices in laboratory culture management often include cryopreservation of microbiota, but this can be challenging with some virus particles. By preserving viral isolates researchers can mitigate genetic drift and laboratory-induced selection, thereby maintaining genetically consistent strains between experiments. To this end, we developed a method to cryopreserve the model, green-alga infecting virus, Paramecium bursaria Chlorella virus 1 (PBCV-1). We explored cryotolerance of the infectivity of this virus particle, whereby freezing without cryoprotectants was found to maintain the highest infectivity (~2.5%). We then assessed the cryopreservation potential of PBCV-1 during an active infection cycle in its Chlorella variabilis NC64A host, …

Pancreas Of Coxsackievirus-Infected Dams And Their Challenged Pups: A Complex Issue, Sona Sarmirova, Maria Borsanyiova, Brigita Benkoova, Michaela Pospisilova, Rajkumar Rajasekaran, Katarina Berakova, Pavol Gomolcak, Jay Reddy, Shubhada Bopegamage

School of Veterinary and Biomedical Sciences: Faculty Publications

Enteroviral infections are frequent, often asymptomatic in humans and during gravidity. The present study is an extension of our previous investigations where we had shown pancreatitis in challenged pups of CVB4-E2-infected dams. Present investigation describes the effect of gestational infection with this virus on the pancreas of both dams and their challenged pups. Gravid CD1 outbred mice were orally infected with CVB4-E2 virus at different gestation times. Pups were challenged orally with the same virus after 25 days of birth. Organs were collected at selected intervals postinfection (p.i.), and replicating virus and viral-RNA copies were analyzed. Additional readouts included histopathology …

The Role Of Isothiocyanates As Cancer Chemo‐Preventive, Chemo‐Therapeutic And Anti‐Melanoma Agents, Melina Mitsiogianni, Georgios Koutsidis, Nikos Mavroudis, Dimitrios T. Trafalis, Sotiris Botaitis, Rodrigo Franco, Vasilis Zoumpourlis, Tom Amery, Alex Galanis, Aglaia Pappa, Mihalis I. Panayiotidis

School of Veterinary and Biomedical Sciences: Faculty Publications

Many studies have shown evidence in support of the beneficial effects of phytochemicals in preventing chronic diseases, including cancer. Among such phytochemicals, sulphur‐containing compounds (e.g., isothiocyanates (ITCs)) have raised scientific interest by exerting unique chemopreventive properties against cancer pathogenesis. ITCs are the major biologically active compounds capable of mediating the anticancer effect of cruciferous vegetables. Recently, many studies have shown that a higher intake of cruciferous vegetables is associated with reduced risk of developing various forms of cancers primarily due to a plurality of effects, including (i) metabolic activation and detoxification, (ii) inflammation, (iii) angiogenesis, (iv) metastasis and (v) regulation …

Fire Legacies In Eastern Ponderosa Pine Forests, Caleb P. Roberts, Victoria M. Donovan, Carissa L. Wonkka, Larkin A. Powell, Craig R. Allen, David G. Angeler, David A. Wedin, Dirac L. Twidwell Jr

Department of Agronomy and Horticulture: Faculty Publications

Disturbance legacies structure communities and ecological memory, but due to increasing changes in disturbance regimes, it is becoming more difficult to characterize disturbance legacies or determine how long they persist. We sought to quantify the characteristics and persistence of material legacies (e.g., biotic residuals of disturbance) that arise from variation in fire severity in an eastern ponderosa pine forest in North America. We compared forest stand structure and understory woody plant and bird community composition and species richness across unburned, low‐, moderate‐, and high‐severity burn patches in a 27‐year‐old mixed‐severity wildfire that had received minimal post‐fire management. We identified distinct …

Spatial Variability Of Soil Properties Under Different Land Use In The Dang District Of Nepal, Dinesh Panday, Roshan Babu Ojha, Devraj Chalise, Saurav Das, Bikesh Twanabasu

Department of Agronomy and Horticulture: Faculty Publications

Increased nutrient mining, soil erosion, and limited nutrient management has led to declines in soil quality and reduced productivity in many parts of Nepal. A study was conducted in the eastern part of the Dang district of Nepal in 2015 to assess the variability of selected soil properties of three different land use types (agricultural, agroforestry, and grassland) and to map their spatial distribution. A total of 120 soil samples were collected from 0–15 cm depth and analyzed for soil fertility parameters: pH, organic matter (OM), nitrogen (N), phosphorus (P), potassium (K), boron (B), and zinc (Zn). Results revealed that …

Utilizing Trait Networks And Structural Equation Models As Tools To Interpret Multi‑Trait Genome‑Wide Association Studies, Mehdi Momen, Malachy T. Campbell, Harkamal Walia, Gota Morota

Department of Agronomy and Horticulture: Faculty Publications

Background: Plant breeders seek to develop cultivars with maximal agronomic value, which is often assessed using numerous, often genetically correlated traits. As intervention on one trait will affect the value of another, breeding decisions should consider the relationships among traits in the context of putative causal structures (i.e., trait networks). While multi-trait genome-wide association studies (MTM-GWAS) can infer putative genetic signals at the multivariate scale, standard MTM-GWAS does not accommodate the network structure of phenotypes, and therefore does not address how the traits are interrelated. We extended the scope of MTM-GWAS by incorporating trait network structures into GWAS using structural …

Cover Crops And Corn Residue Removal: Impacts On Soil Hydraulic Properties And Their Relationships With Carbon, Michael Sindelar, Humberto Blanco-Canqui, Virginia L. Jin, Richard B. Ferguson

Department of Agronomy and Horticulture: Faculty Publications

Large-scale crop residue removal may negatively affect soil water dynamics. Integrating cover crop (CC) with crop residue management can be a strategy to offset potential adverse effects of residue removal. We studied: (i) the impact of corn (Zea mays L.) residue removal (56%) with and without the use of winter rye (Secale cereale L.) CC on soil hydraulic properties, (ii) whether CC would ameliorate residue removal effects on hydraulic properties, and (iii) relationships of hydraulic properties with soil organic C (SOC) and other properties under irrigated no-till continuous corn on a silt loam in south central Nebraska after …

Genetic Diversity And Population Structure Of A Camelina Sativa Spring Panel, Zinan Luo, Jordan Brock, John M. Dyer, Toni Kutchan, Daniel P. Schachtman, Megan Augustin, Yufeng Ge, Noah Fahlgren, Hussein Abdel-Haleem

Department of Agricultural and Biological Systems Engineering: Faculty Publications

There is a need to explore renewable alternatives (e.g., biofuels) that can produce energy sources to help reduce the reliance on fossil oils. In addition, the consumption of fossil oils adversely affects the environment and human health via the generation of waste water, greenhouse gases, and waste solids. Camelina sativa, originated from southeastern Europe and southwestern Asia, is being re-embraced as an industrial oilseed crop due to its high seed oil content (36–47%) and high unsaturated fatty acid composition (>90%), which are suitable for jet fuel, biodiesel, high-value lubricants and animal feed. C. sativa’s agronomic advantages include …

Nucleic Acid Delivery To Mesenchymal Stem Cells: A Review Of Nonviral Methods And Applications, Andrew Hamann, Albert Nguyen, Angela K. Pannier

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Background: Mesenchymal stem cells (MSCs) are multipotent stem cells that can be isolated and expanded from many tissues, and are being investigated for use in cell therapies. Though MSC therapies have demonstrated some success, none have been FDA approved for clinical use. MSCs lose stemness ex vivo, decreasing therapeutic potential, and face additional barriers in vivo, decreasing therapeutic efficacy. Culture optimization and genetic modification of MSCs can overcome these barriers. Viral transduction is efficient, but limited by safety concerns related to mutagenicity of integrating viral vectors and potential immunogenicity of viral antigens. Nonviral delivery methods are safer, though limited …

Ecophysiological Determinants Of Sexual Size Dimorphism: Integrating Growth Trajectories, Environmental Conditions, And Metabolic Rates, Marie-Claire Chelini, John P. Delong, Eileen A. Hebets

Eileen Hebets Publications

Sexual size dimorphism (SSD) often results in dramatic differences in body size between females and males. Despite its ecological importance, little is known about the relationship between developmental, physiological, and energetic mechanisms underlying SSD. We take an integrative approach to understand the relationship between developmental trajectories, metabolism, and environmental conditions resulting in extreme female-biased SSD in the crab spider Mecaphesa celer (Thomisidae). We tested for sexual differences in growth trajectories, as well as in the energetics of growth, hypothesizing that female M. celer have lower metabolic rates than males or higher energy assimilation. We also hypothesized that the environment in …

Agenator: An Open Source Computer-Controlled Dry Aging System For Beef, Soon Kiat Lau, Felipe Azevedo Ribeiro, Jeyamkondan Subbiah, Chris R. Calkins

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Dry aging of beef is a process where beef is exposed to a controlled environment with the ultimate goal of drying the beef to improve its quality and value. Comprehensive investigations into the effects of various environmental conditions on dry aging are crucial for understanding and optimizing the process, but the lack of affordable equipment focused on data collection makes it difficult to do so. The Agenator was thus developed as an open source system with a suite of features for investigating dry aging such as: measuring and recording relative humidity, temperature, mass, air velocity, and fan rotational speed; precise …

Heterologous Expression And Functional Characterization Of A Gh10 Endoxylanase From Aspergillus Fumigatus Var. Niveus With Potential Biotechnological Application, Josman Velasco, Bianca Oliva, Evandro Jose Mulinari, Leidy Patricia Quintero, Awana Da Silva Lima, Aline Larissa Goncalves, Thiago Augusto Goncalves, Andre Damasio, Fabio Marcio Squina, Adriane Maria Ferreira Milagres, Asmaa Abdella, Mark R. Wilkins, Fernando Segato

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Xylanases decrease the xylan content in pretreated biomass releasing it from hemicellulose, thus improving the accessibility of cellulose for cellulases. In this work, an endo-β-1,4-xylanase from Aspergillus fumigatus var. niveus (AFUMN-GH10) was successfully expressed. The structural analysis and biochemical characterization showed this AFUMN-GH10 does not contain a carbohydrate-binding module. The enzyme retained its activity in a pH range from 4.5 to 7.0, with an optimal temperature at 60°C. AFUMN-GH10 showed the highest activity in beechwood xylan. The mode of action of AFUMNGH10 was investigated by hydrolysis of APTS-labeled xylohexaose, which resulted in xylotriose and xylobiose as the main products. AFUMN-GH10 …

Antibiotic Resistance Gene Profile Changes In Cropland Soil After Manure Application And Rainfall, Morgan Meyers, Lisa Durso, John E. Gilley, Heidi Waldrip, Lana Castleberry, Amy Millmier Schmidt

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Land application of manure introduces gastrointestinal microbes into the environment, including bacteria carrying antibiotic resistance genes (ARGs). Measuring soil ARGs is important for active stewardship efforts to minimize gene flow from agricultural production systems; however, the variety of sampling protocols and target genes makes it difficult to compare ARG results between studies. We used polymerase chain reaction (PCR) methods to characterize and/or quantify 27 ARG targets in soils from 20 replicate, long-term no-till plots, before and after swine manure application and simulated rainfall and runoff. All samples were negative for the 10 b-lactamase genes assayed. For tetracycline resistance, only source …

The Effects Of Management Practices On Grassland Birds: An Introduction To North American Grasslands And The Practices Used To Manage Grasslands And Grassland Birds, Jill A. Shaffer, John P. Delong

Papers in Ornithology

Summary

The Great Plains of North America is defined as the land mass that encompasses the entire central portion of the North American continent that, at the time of European settlement, was an unbroken expanse of primarily herbaceous vegetation. The Great Plains extend from central Saskatchewan and Alberta to central Mexico and from Indiana to the Rocky Mountains. The expanses of herbaceous vegetation are often referred to as native prairie or native grasslands. Native grasslands share the characteristics of a general uniformity in vegetation structure, dominance by grasses and forbs, a near absence of trees and shrubs, annual precipitation ranging …

Distribution Extension Of Aspiculuris Americana Parasite Of Peromyscus Difficilis In Hidalgo, Mexico, Griselda Pulido-Flores, Scott Monks, Jorge Falcón-Ordaz

Harold W. Manter Laboratory of Parasitology: Faculty Publications

English: As a part of an ongoing project to inventory the helminth parasites of rodents in Mexico, 30 individuals of Aspiculuris americana were collected inhabiting the intestine from three specimens of the rock mouse Peromyscus difficilis, collected from Cerro Xihuingo, Municipality of Tepeapulco, Hidalgo State, Mexico. This species of nematode parasite different species of the genus Peromyscus (P. gossypinus, P. leucopus, P. maniculatus, and P. floridanus) distributed from Yukon Territory in Canada to Florida in the United States of America. This is the first report of Aspiculuris americana in a Mexican endemic rodent, widening …

Pine-Wood Derived Nanobiochar For Removal Of Carbamazepine From Aqueous Media: Adsorption Behavior And Influential Parameters, Mitra Naghdi, Mehrdad Taheran, Rama Pulicharla, Tarek Rouissi, Satinder K. Brar, M. Verma, R. Y. Surampalli

Department of Civil and Environmental Engineering: Faculty Publications

In recent years, application of biochar for removal of pollutants from aqueous solutions has been of interest due to favorable physicochemical properties and availability of feedstock. However, adsorption behavior has been reported only for raw and micro biochar particles and taking advantage of biochar nanoparticles, which offer superior specific surface area, did not receive any attention. The objective of this study was to investigate the adsorption efficiency of produced nanobiochar from pinewood. For this purpose, removal of carbamazepine (CBZ), a globally prescribed pharmaceutical, at very low concentrations (0.5–20 ppb) on as-produced nanobiochar with average particle size of 60 nm was …

Taking The Bait: Species Taking Oral Rabies Vaccine Baits Intended For Raccoons, Betsy S. Haley, Are R. Berentsen, Richard M. Engeman

United States Department of Agriculture Wildlife Services: Staff Publications

Raccoon rabies in eastern USA is managed by strategically distributing oral rabies vaccine (ORV) baits. The attractiveness, palativity, density, and non-target species bait take affect ORV effectiveness. We examined raccoon and non-target species differences in investigating/removing fish-meal polymer and coated sachet baits applied to simulate two aerial bait distribution densities. Bait densities of 150 baits/km2 and 75 baits/km2 were evaluated, respectively, in zones expected to have high and low

Racc oon densities. Three primary non-target species visited baits: coyotes, white-tailed deer, and feral swine. The proportion of bait stations visited by raccoons during 1 week observation periods ranged from 50 …

Using Unmanned Aerial Vehicles For Bird Harassment On Fish Ponds, Ciera A. Rhoades, Peter J. Allen, D. Tommy King

United States Department of Agriculture Wildlife Services: Staff Publications

The effects of aquaculture decline on piscivorous birds in the Mississippi Delta concern catfish farmers, with possible increases in fish loss and disease transmission. Piscivorous birds quickly habituate to most current methods of harassment (loud noises and visual disturbances) leading to increased depredation and disease. Our study was designed to test the efficacy of using unmanned aerial vehicles (UAVs) to effectively control piscivorous birds at fish farms. We hypothesized that a UAV would be more efficient at reducing the number of fish-eating birds on fish ponds than current forms of harassment. We conducted pre-treatment bird surveys, harassment observations, and post-treatment …

Physiological And Genomic Evidence That Selection On The Transcription Factor Epas1 Has Altered Cardiovascular Function In Highaltitude Deer Mice, Rena M. Schweizer, Jonathan P. Velotta, Catherine M. Ivy, Matthew R. Jones, Sarah M. Muir, Gideon S. Bradburd, Jay F. Storz, Graham R. Scott, Zachary A. Cheviron

School of Biological Sciences: Faculty Publications

Evolutionary adaptation to extreme environments often requires coordinated changes in multiple intersecting physiological pathways, but how such multi-trait adaptation occurs remains unresolved. Transcription factors, which regulate the expression of many genes and can simultaneously alter multiple phenotypes, may be common targets of selection if the benefits of induced changes outweigh the costs of negative pleiotropic effects. We combined complimentary population genetic analyses and physiological experiments in North American deer mice (Peromyscus maniculatus) to examine links between genetic variation in transcription factors that coordinate physiological responses to hypoxia (hypoxia-inducible factors, HIFs) and multiple physiological traits that potentially contribute to …

Differential Spatial Gradients Of Wheat Streak Mosaic Virus Into Winter Wheat From A Central Mite-Virus Source, Abby R. Stilwell, Donald Rundquist, David B. Marx, Gary L. Hein

Department of Entomology: Faculty Publications

The wheat curl mite (WCM), Aceria tosichella Keifer, transmits three potentially devastating viruses to winter wheat. An increased understanding of mite movement and subsequent virus spread through the landscape is necessary to estimate the risk of epidemics by the virus in winter wheat. Owing to the small size of WCMs, their dispersal via wind is hard to monitor; however, the viruses they transmit produce symptoms that can be detected with remote sensing. The objective of this study was to characterize the spatial dispersal of the virus from a central mite-virus source. Virus infection gradients were measured spatially by using aerial …

Necrobiome Framework For Bridging Decomposition Ecology Of Autotrophically And Heterotrophically Derived Organic Matter, M. Eric Benbow, Philip S. Barton, Michael D. Ulyshen, James C. Beasley, Travis L. Devault, Michael S. Strickland, Jeffery K. Tomberlin, Heather R. Jordan, Jennifer L. Pechal

United States Department of Agriculture Wildlife Services: Staff Publications

Decomposition contributes to global ecosystem function by contributing to nutrient recycling, energy flow, and limiting biomass accumulation. The decomposer organisms influencing this process form diverse, complex, and highly dynamic communities that often specialize on different plant or animal resources. Despite performing the same net role, there is a need to conceptually synthesize information on the structure and function of decomposer communities across the spectrum of dead plant and animal resources. A lack of synthesis has limited cross-disciplinary learning and research in important areas of ecosystem and community ecology. Here we expound on the “necrobiome” concept and develop a framework describing …

In Vitro Bioaccessibility Of Novel Low-Crystallinity Phytosterol Nanoparticles In Non-Fat And Regular-Fat Foods, Ali Ubeyitogullari, Ozan Ciftci

Department of Food Science and Technology: Faculty Publications

Crystalline structure of phytosterols leads to poor bioavailability and makes their incorporation into foods challenging. Bioaccessibility of first-of-their-kind low-crystallinity phytosterol nanoparticles impregnated in nanoporous starch aerogels (PS-NSA) was evaluated in non-, low-, and regular-fat solid and aqueous food formulations, namely, granola bars and puddings for the first time. Bioaccessibility of the phytosterol nanoparticles was significantly higher than that of crude phytosterols in all food formulations (p < .05); it was 88.2 and 91.8% for low- or regular-fat granola bars, respectively, whereas bioaccessibility of crude phytosterols was ca. 30% in those formulations. However, decreasing the lipid content to zero resulted in lower phytosterols' bioaccessibilities from both PS-NSA (53%) and crude phytosterols (ca. 16%) in non-fat granola bars. Bioaccessibility of crude phytosterols (2%) was significantly enhanced with PS-NSA (19%) in the pudding formulation. PS-NSA allows preparation of low- and non-fat foods enriched with phytosterols while enhancing the health benefits of phytosterols with smaller doses.

Hemodynamic Interference Of Serial Stenoses And Its Impact On Ffr And Ifr Measurements, Siyeong Ju, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

The hemodynamic interference of serial stenoses poses challenges for identifying the functional severity using the fractional flow reserve (FFR) method. The instantaneous wave-free ratio (iFR), i.e., the distal-to-proximal pressure ratio at 75% of diastole, was recently proposed to overcome the disadvantages of the FFR. However, the underlying mechanism remained ambiguous due to the lack of quantitative definition of hemodynamic interference. The objective of this study is to quantitatively define the hemodynamic interference and then examine its role on the FFR and iFR measurements. Pressure distributions, velocity fields, and Q-criterion which identifies vortices, were obtained through the computational fluid dynamics (CFD) …

Hemodynamics And Wall Mechanics After Surgical Repair Of Aortic Arch: Implication For Better Clinical Decisions, Siyeong Ju, Ibrahim Abdullah, Shengmao Lin, Linxia Gu

Department of Mechanical and Materials Engineering: Faculty Publications

Graft repair of aortic coarctation is commonly used to mimic the physiological aortic arch shape and function. Various graft materials and shapes have been adopted for the surgery. The goal of this work is to quantitatively assess the impact of graft materials and shapes in the hemodynamics and wall mechanics of the restored aortic arch and its correlation with clinical outcomes. A three-dimensional aortic arch model was reconstructed from magnetic resonance images. The fluid–structure interaction (FSI) analysis was performed to characterize the hemodynamics and solid wall mechanics of the repaired aortic arch. Two graft shapes (i.e., a half-moon shape and …

Identification Of Sero-Diagnostic Antigens For The Early Diagnosis Of Johne’S Disease Using Map Protein Microarrays, Lingling Li, J. P. Bannantine, Joseph J. Campo, Arlo Randall, Yrjo T. Grohn, Megan A. Schilling, Robab Katani, Jessica Radzio-Basu, Laurel Easterling, Vivek Kapur

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Considerable effort has been directed toward controlling Johne’s disease (JD), a chronic granulomatous intestinal inflammatory disease caused by Mycobacterium avium subsp. paratuberculosis (MAP) in cattle and other ruminants. However, progress in controlling the spread of MAP infection has been impeded by the lack of reliable diagnostic tests that can identify animals early in the infection process and help break the transmission chain. To identify reliable antigens for early diagnosis of MAP infection, we constructed a MAP protein array with 868 purified recombinant MAP proteins, and screened a total of 180 well-characterized serum samples from cows assigned to 4 groups based …

Quantification Of Macrophages And Mycobacterium Avium Subsp. Paratuberculosis In Bovine Intestinal Tissue During Different Stages Of Johne’S Disease, Caitlin J. Jenvey, Jesse M. Hostetter, Adrienne L. Shircliff, John Bannantine, Judith R. Stabel

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Johne’s disease is an enteric disease caused by the intracellular pathogen Mycobacterium avium subsp. paratuberculosis (MAP). Upon ingestion of MAP, it is translocated across the intestinal epithelium and may be killed by intestinal macrophages, or depending on the bacterial burden and immunological status of the animal, MAP may thwart innate defense mechanisms and persist within the macrophage. This study aimed to determine the numbers of macrophages and MAP present in bovine midileal tissue during different stages of infection. Immunofluorescent (IF) labeling was performed on frozen bovine midileal intestinal tissue collected from 28 Holstein dairy cows. The number of macrophages in …

Wolves: A Primer For Ranchers, John Williams, Douglas E. Johnson, Patrick E. Clark, Larry L. Larson, Tyanne J. Roland

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Ranch management has become more complex since wolves were reintroduced into Idaho and Wyoming in 1996. In wolf areas, livestock have experienced increased death loss and greater stress. Increased livestock aggressiveness has been observed, especially toward working dogs, making handling livestock more difficult. Additionally ranchers have reported a loss of body condition, lower conception rates, increased time and expense for management. Our study was designed to investigate the effect of wolf presence on cattle behavior, landscape use patterns, and resource selection by comparing high wolf density areas against low wolf density areas. This study also generated baseline information on cattle …