Digital Commons Network^™

Investigation Of A Novel Non-Surgical Method Of Artificial Insemination For Sheep, P. H. Purdy, H. D. Blackburn, B. Larson, R. Stobart

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

Transcervical artificial insemination (AI) with sheep is not frequently used in the US due to low fertility rates. Consequently, laparoscopic AI has been employed to circumvent this situation. The problem with this technique is that while it provides satisfactory levels of fertility the degree of technical expertise necessary to perform the procedure, the costs associated with purchasing equipment, and/or the costs of hiring an inseminator are prohibitive for many producers. Therefore, the purpose of this study was to investigate a transcervical method of AI that is nonsurgical, simple to perform, and inexpensive. The estrous cycles of 40 ewes …

Effect Of Using Threadfin Shad As Forage For Channel Catfish Fed Daily Or Every Third Day, Bartholomew W. Green, Peter Perschbacher, Gerald Ludwig

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

We evaluated whether stocking threadfin shad Dorosoma petenense as a forage fish in multiple-batch production ponds for channel catfish Ictalurus punctatus could substitute for formulated feed when channel catfish were fed daily or every 3 d. A completely randomized design in a 232 factorial arrangement was used for the experiment, which was conducted in twelve 0.1-ha earthen ponds. Prespawn adult threadfin shad were stocked at 404 kg/ha in six of the ponds, whereas the remaining ponds received no threadfin shad. Channel catfish stockers (0.35 kg/fish) were stocked at 5,040 kg/ha, and fingerlings (28.2 g/fish) were stocked at 14,820 fish/ha. Channel …

Particle Size Effects On The Quality Of Flour Tortillas Enriched With Whole Grain Waxy Barley, Naruemon Prasopsunwattana, Marfa Botero Omary, Elizabeth A. Arndt, Peter H. Cooke, Rolando A. Flores, Wallace Yokoyama, Ayako Toma, Sutida Chongcham, Sylvia P. Lee

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

Wheat tortillas were enriched with whole barley flour (WBF) of different particle sizes including 237 µm (regular [RD. 131 µm (intermediate [IM]). and 68 µm (microground [MG], Topographical and fluorescent microstructure images of flours, doughs, and tortillas were examined, Flours and tortillas were analyzed for color, protein, ash, starch, moisture. and β-glucan content. Farinograph testing was conducted on the flour blends, Water activity and texture analyses of tortillas were conducted, A 9-point hedonic scale was used by 95 untrained panelists to evaluate tortilla appearance, color, flavor, texture, and overall acceptability, Two commercial products (CP) were included in …

Reproductive And Sphingolipid Metabolic Effects Of Fumonisin B1 And Its Alkaline Hydrolysis Product In Lm/Bc Mice: Hydrolyzed Fumonisin B1 Did Not Cause Neural Tube Defects, Kenneth A. Voss, Ronald T. Riley, Maurice E. Snook, Janee Gelineau-Van Waes

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

Fumonisins are mycotoxins produced by Fusarium verticillioides. They are toxic to animals and exert their effects through mechanisms involving disruption of sphingolipid metabolism. Fumonisins are converted to their hydrolyzed analogs by alkaline cooking (nixtamalization). Both fumonisins and hydrolyzed fumonisins are found in nixtamalized foods such as tortillas, and consumption of tortillas has been implicated as a risk factor for neural tube defects (NTD). Fumonisin B₁ (FB₁) induced NTD when given (ip) to pregnant LM/Bc mice; however, neither the NTD induction potential of hydrolyzed fumonisin B₁ (HFB₁) nor its affect on sphingolipid metabolism in …

Effects Of Spontaneous Heating On Fiber Composition, Fiber Digestibility, And In Situ Disappearance Kinetics Of Neutral Detergent Fiber For Alfalfa-Orchardgrass Hays, W. K. Coblentz, P. C. Hoffman

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

During 2006 and 2007, forages from 3 individual hay harvests were utilized to assess the effects of spontaneous heating on concentrations of fiber components, 48-h neutral detergent fiber (NDF) digestibility (NDFD), and in situ disappearance kinetics of NDF for large-round bales of mixed alfalfa (Medicago sativa L.) and orchardgrass (Dactylis glomerata L.). Over the 3 harvests, 96 large-round bales were made at preset bale diameters of 0.9, 1.2, or 1.5 m, and at moisture concentrations ranging from 9.3 to 46.6%. Internal bale temperatures were monitored daily during an outdoor storage period, reaching maxima (MAX) of 77.2°C and 1,997 heating degree …

Promoting Parent Partnership In Head Start: A Qualitative Case Study Of Teacher Documents From A School Readiness Intervention Project., Carolyn P. Edwards, Tara Hart, Kelly Rasmussen, Y. M. Haw, Susan M. Sheridan

Department of Child, Youth, and Family Studies: Faculty Publications

To advance the field of children’s services, implementation and generalization studies are needed to help us reveal the inner workings of intervention projects and how they do (or do not) achieve their outcomes. This paper provides a case study of Head Start teachers’ uptake of the Getting Ready school readiness intervention, intended to strengthen professionals’ capacity to support parental engagement in young children’s development and learning. The qualitative method of document review was used in scrutinizing home visit reports and classroom newsletters as a source of authentic evidence about teachers’ implementation and generalization of an early intervention model. Home visits …

Gene Expression Profiling Of Tolerant Barley In Response To Diuraphis Noxia (Hemiptera: Aphididae) Feeding, A. Gutsche, Tiffany Heng-Moss, Gautam Sarath, P. Twigg, Yuannan Xia, G. Lu, D. Mornhinweg

Department of Entomology: Faculty Publications

Aphids are, arguably, the single most damaging group of agricultural insect pests throughout the world. Plant tolerance, which is a plant response to an insect pest, is viewed as an excellent management strategy. Developing testable hypotheses based on genome-wide and more focused methods will help in understanding the molecular underpinnings of plant tolerance to aphid herbivory. As a first step in this process, we undertook transcript profiling with Affymetrix GeneChip Barley Genome arrays using RNA extracted from tissues of tolerant and susceptible genotypes collected at three hours, three days and six days after Diuraphis noxia introduction. Acquired data were compared …

Using The World Wide Web To Educate And Inform The Public About Risk And Agricultural Biotechnology, Douglas A. Golick, Robert D. Peterson, Leon G. Higley

Department of Entomology: Faculty Publications

The University of Nebraska and AgBios, Inc. launched the AgBiosafety website (http://agbiosaftzy.unl.edu) with the purpose of educating the public about agricultural biotechnology risk and safezy issues through science-based content. This article discusses the creation ofthe website, its components, and data gathered from usage statistics and a web-delivered survey. Also included is a discussion of the results ofdata gathered and recommendations for future web-based educational efforts in biotechnology safety and risk assessment.

A Serological Survey Of Infectious Disease In Yellowstone National Park’S Canid Community, Emily S. Almberg, L. David Mech, Douglas W. Smith, Jennifer W. Sheldon, Robert L. Crabtree

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Background: Gray wolves (Canis lupus) were reintroduced into Yellowstone National Park (YNP) after a .70 year absence, and as part of recovery efforts, the population has been closely monitored. In 1999 and 2005, pup survival was significantly reduced, suggestive of disease outbreaks.

Methodology/Principal Findings: We analyzed sympatric wolf, coyote (Canis latrans), and red fox (Vulpes vulpes) serologic data from YNP, spanning 1991–2007, to identify long-term patterns of pathogen exposure, identify associated risk factors, and examine evidence for disease-induced mortality among wolves for which there were survival data. We found high, constant exposure to canine …

Choline-Utilizing Microblal Strains For Biologically Controlling Fusarium Head Blight, David A. Schisler, Naseem I. Khan, Michael J. Boehm, Patricia J. Slininger

Department of Plant Pathology: Faculty Publications

Three choline utilizing strains of microorganisms isolated from the anthers of wheat, Aureobasidium pullulans strainAS 55.2, Arthrobacter species strain OH 221.3, and Pseudomonas species strain AS 64.4, are superior antagonists of F. graminearum. These microorganisms are effective for suppression and control of FHB in cereals, particularly in wheat and barley.

Plant-Microbes Interactions In Enhanced Fertilizer-Use Efficiency, Anthony O. Adesemoye, Joseph W. Kloepper

Department of Plant Pathology: Faculty Publications

The continued use of chemical fertilizers and manures for enhanced soil fertility and crop productivity often results in unexpected harmful environmental effects, including leaching of nitrate into groundwater, surface runoff of phosphorus and nitrogen runoff, and eutrophication of aquatic ecosystems. Integrated nutrient management systems are needed to maintain agricultural productivity and protect the environment. Microbial inoculants are promising components of such management systems. This review is a critical summary of the efforts in using microbial inoculants, including plant growth-promoting rhizobacteria and arbuscular mycorrhizal fungi for increasing the use efficiency of fertilizers. Studies with microbial inoculants and nutrients have demonstrated that …

Spontaneous Idiopathic Arteritis Of The Testicular Artery In Raccoons (Procyon Lotor), A. N. Hamir, M. V. Palmer, H. Li, J. Stasko, D. G. Rogers

School of Veterinary and Biomedical Sciences: Faculty Publications

The testes and the spermatic cord of raccoons (Procyon lotor, kits to adult breeders; n = 48) were examined. Segmental arteritis confined to the extratesticular portions of the testicular artery was present in raccoons of all ages. The arterial changes were seen in laboratory-confined experimental and control animals as well as in wild-caught raccoons. The lesions consisted of proliferative endarteritis with presence of inflammatory cells within the intima, media, and the adventitial regions of most affected vessels. Some aspects of the proliferative arterial lesions were reminiscent of systemic necrotizing vasculitis (polyarteritis nodosa), an immunologically mediated condition of animals and humans. …

Evaluation Of The Waxy Endosperm Trait In Proso Millet (Panicum Miliaceum), Robert A. Graybosch, D. D. Baltensperger

Department of Agronomy and Horticulture: Faculty Publications

The entire USDA-ARS maintained collection of 650 accessions of proso millet (Panicum miliaceum L.) was evaluated for the presence of accessions with waxy (amylose-free) endosperm starch. Six accessions, five of which derived from mainland China, were identified. Segregation ratios for waxy endosperm were evaluated in F₂ and F₃ populations derived from crosses between two waxy accessions, PI 436625 (Lung Shu 16) and PI 436626 (Lung Shu 18), and several wildtype accessions. The waxy trait was found to be under the control of duplicate recessive alleles at two loci, herein designated wx-1 and wx-2. Wild-type alleles at …

Nutrient And Chemical Properties Of Aging Golf Course Putting Greens As Impacted By Soil Depth And Mat Development, Ty A. Mcclellan, Roch E. Gaussoin, Bob Shearman, Charles S. Wortmann, Martha Mamo, Garald L. Horse, David B. Marx

Department of Agronomy and Horticulture: Faculty Publications

Nutrient and chemical changes in turfgrass sand-based root zones are not well understood. This study was conducted to characterize nutrient and chemical properties in putting greens influenced by root zone mixture and establishment treatment, putting green age, and soil depth. Putting greens were constructed and established with Agrostis stolonifera L. in sequential years from 1997 to 2000. Treatments included root zone mixtures of 80:20 (v:v) sand and sphagnum peat and 80:15:5 (v:v:v) sand, sphagnum peat, and soil, and accelerated versus controlled establishment. In the establishment year, the accelerated treatment received 2.6-, 3.0-, and 2.6-fold more nitrogen, phosphorus, and potassium, respectively, …

X-Ray Fluorescence Microscopy Reveals The Role Of Selenium In Spermatogenesis, Sebastian Kehr, Mikalai I. Malinouski, Lydia Finney, Stefan Vogt, Vyacheslav M. Labunskyy, Marina V. Kasaikina, Bradley A. Carlson, You Zhou, Dolph L. Hatfield, Vadim N. Gladyshev

Vadim Gladyshev Publications

Selenium (Se) is a trace element with important roles in human health. Several selenoproteins have essential functions in development. However, the cellular and tissue distribution of Se remains largely unknown because of the lack of analytical techniques that image this element with sufficient sensitivity and resolution. Herein, we report that X-ray fluorescence microscopy (XFM) can be used to visualize and quantify the tissue, cellular and subcellular topography of Se. We applied this technique to characterize the role of Se in spermatogenesis and identified a dramatic Se enrichment specifically in late spermatids, a pattern that was not seen in any other …

Improved Sugar Conversion And Ethanol Yield For Forage Sorghum (Sorghum Bicolor L. Moench) Lines With Reduced Lignin Contents, Bruce S. Dien, Gautam Sarath, Jeffrey F. Pedersen, Scott E. Sattler, Han Chen, Deanna L. Funnell-Harris, Nancy N. Nichols, Michael A. Cotta

Gautam Sarath Publications

Lignin is known to impede conversion of lignocellulose into ethanol. In this study, forage sorghum plants carrying brown midrib (bmr) mutations, which reduce lignin contents, were evaluated as bioenergy feedstocks.

Arginine-Induced Germ Tube Formation In Candida Albicans Is Essential For Escape From Murine Macrophage Line Raw 264.7, Suman Ghosh, Dhammika H. M. L. P. Navarathna, David D. Roberts, Jake T. Cooper, Audrey L. Atkin, Thomas M. Petro, Kenneth W. Nickerson

School of Biological Sciences: Faculty Publications

The opportunistic fungal pathogen Candida albicans is a part of the normal flora but it also causes systemic candidiasis if it reaches the bloodstream. Upon being phagocytized by macrophages, an important component of innate immunity, C. albicans rapidly upregulates a set of arginine biosynthetic genes. Arginine, urea, and CO2 induced hyphae in a density-dependent manner in wild-type, cph1/cph1, and rim101/rim101 strains but not in efg1/efg1 or cph1/cph1 efg1/efg1 strains. Arginase (Car1p) converts arginine to urea, which in turn is degraded by urea amidolyase (Dur1,2p) to produce CO2, a signal for hyphal switching. We used a dur1,2/dur1,2 mutant (KWN6) and the …

Bess: BIofuel ENergy SYstems SImulator: Life Cycle Energy & Emissions Analysis Model For Corn-Ethanol Biofuel Production Systems -- User’S Guide For The Bess Model, Adam Liska, Haishun Yang, Daniel T. Walters, Kenneth Cassman, Terry Klopfenstein, Galen Erickson, Virgil R. Bremer, Richard K. Koelsch, Dan Kenney, Patrick Tracy

Adam Liska Papers

The BESS model is a software tool to calculate the energy efficiency, greenhouse gas (GHG) emissions, and natural resource requirements of corn–to-ethanol biofuel production systems. The model provides a “cradle-to-grave” analysis of the production life cycle of biofuels from the creation of material inputs to finished products, producing an inventory of distributed GHG emissions from fossil fuels and a few key indirect emissions in the production life cycle. The model parameters can be set by the user to achieve the highest accuracy in evaluating a single corn-ethanol biorefinery and its surrounding feedstock crop production zone. The model equations and summary …

Triacylglyceride Metabolism By Fusarium Graminearum During Colonization And Sexual Development On Wheat, John C. Guenther, Heather E. Hallen-Adams, Heike Bücking, Yair Shachar-Hill, Frances Trail

Department of Food Science and Technology: Faculty Publications

Fusarium graminearum, a devastating pathogen of small grains, overwinters on crop residues and produces ephemeral perithecia. Accumulation of lipids in overwintering hyphae would provide reserves for overwinter survival and perithecium development. Fatty acid composition of cultures during perithecium development indicated a drop in neutral lipid levels during development but little change in fatty acid composition across stages. Microscopic examination of cultures early in sexual development revealed hyphal cells engorged with lipid bodies. In comparison, vegetative hyphae contained few lipid bodies. Microarray analysis was performed on wheat stems at stages of colonization through perithecium development. Gene expression analysis during stages of …

Diet-Induced Metabolic Improvements In A Hamster Model Of Hypercholesterolemia Are Strongly Linked To Alterations Of The Gut Microbiota, Inés Martínez, Chaomei Zhang, Ryan Legge, Andrew K. Benson, Timothy P. Carr, Etsuko N. Moriyama, Jens Walter

Department of Food Science and Technology: Faculty Publications

The mammalian gastrointestinal microbiota exerts a strong influence on host lipid and cholesterol metabolism. In this study, we have characterized the interplay among diet, gut microbial ecology, and cholesterol metabolism in a hamster model of hypercholesterolemia. Previous work in this model had shown that grain sorghum lipid extract (GSL) included in the diet significantly improved the high-density lipoprotein (HDL)/ non-HDL cholesterol equilibrium (T. P. Carr, C. L. Weller, V. L. Schlegel, S. L. Cuppett, D. M. Guderian, Jr., and K. R. Johnson, J. Nutr. 135:2236-2240, 2005). Molecular analysis of the hamsters’ fecal bacterial populations by pyrosequencing of 16S rRNA tags, …

Daily Negative Mood Affects Fasting Glucose In Type 2 Diabetes, Marilyn M. Skaff, Joseph T. Mullan, David M. Almeida, Lesa Hoffman, Umesh Masharani, David C. Mohr, Lawrence Fisher

Department of Psychology: Faculty Publications

Objective—To examine the relationship between mood and blood glucose in a 21 day daily diary study.

Design—During a home visit, information was gathered from two hundred six persons with type 2 diabetes regarding demographics, disease characteristics and treatment, and depressive symptoms. They had blood drawn at a laboratory, yielding HbA1C. The participants were then telephoned each evening for 21 days and were asked about their positive and negative mood during the past 24 hours. They also tested their blood glucose upon rising in the morning.

Main Outcome Measures—The main outcomes measures were positive and negative affect and fasting glucose.

Results—Multilevel …

Low-Level Lead Exposure And Contingency-Based Responding In Preschoolers: An Exploratory Study, Melanie Mcdiarmid Nelson, Kimberly A. Espy

Department of Psychology: Faculty Publications

Two reversal paradigm tasks (spatial reversal and spatial reversal with irrelevant color cues) originally designed to assess contingency-based responding in primates were adapted for use with 139 preschool children with a mean peak blood lead level (BLL) of 4.2 μg/dl (SD = 2.2). Sixty-nine children with BLL ≥ 5 μg/dl and 70 children with BLL of < 5 μg/dl were included. Results indicated that preschool children with low-level lead exposure take longer to learn associations than preschool children with very low levels of lead exposure, and this difference cannot be attributed to increased distractibility or perseverative responding. These results support the use of these measures to assess specific cognitive functions in preschool children.

Acute Effects Of A Thermogenic Nutritional Supplement On Cycling Time To Exhaustion And Muscular Strength In College-Aged Men, Ashley A. Walter, Trent J. Herda, Eric D. Ryan, Pablo B. Costa, Katherine M. Hoge, Travis W. Beck, Jeffrey R. Stout, Joel T. Cramer

Department of Nutrition and Health Sciences: Faculty Publications

Background: The purpose of the present study was to examine the acute effects of a thermogenic nutritional supplement containing caffeine, capsaicin, bioperine, and niacin on muscular strength and endurance performance.

Methods: Twenty recreationally-active men (mean ± SD age = 21.5 ± 1.4 years; stature = 178.2 ± 6.3 cm; mass = 76.5 ± 9.9 kg; VO_{2 PEAK} = 3.05 ± 0.59 L/min^-1) volunteered to participate in this randomized, double-blinded, placebo-controlled, cross-over study. All testing took place over a three-week period, with each of the 3 laboratory visits separated by 7 days (± 2 hours). During the initial …

Comparative Metabolism Of Benzo(A)Pyrene By Ovarian Microsomes Of Various Species, Deacqunita L. Harris, Ashley C. Huderson, Mohammad S. Niaz, J. Joe Ford, Anthony E. Archibong, Aramandla Ramesh

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

Knowledge of the ability of the female reproductive system to metabolize polycyclic aromatic hydrocarbons (PAHs) is critical to the diagnosis and management of female infertility and for risk assessment purposes. The PAHs are a family of widespread pollutants that are released into the environment from automobile exhausts, cigarette smoke, burning of refuse, industrial emissions, and hazardous waste sites. In exposed animals, PAHs become activated to reactive metabolites that interfere with target organ function and as a consequence cause toxicity. The extent of susceptibility to PAH exposure may depend on the ability of animals to metabolize these chemicals. The present study …

Effects Of Maternal Nutritional Plane And Selenium Supply On Cellularity Estimates Of Neonatal Lamb Jejunal Mucosa, Heart, And Skeletal Muscle, T. L. Neville, A. M. Meyer, J. J. Reed, J. B. Taylor, L. P. Reynolds, D. A. Redmer, K. R. Maddock Carlin, K. A. Vonnahme, J. S. Caton

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

Objectives were to investigate the effects of maternal nutrition and Se supply during gestation on lamb jejunal mucosa, heart, and skeletal muscle RNA, DNA, and protein. Rambouillet ewe lambs (n = 84) were allotted to a 2 x 3 factorial design including dietary factors of Se [adequate Se (ASe; 11.5 μg/kg BW) or high Se (HSe; 77.0 μg/kg BW)] and nutritional plane [60% (RES), 100% (CON), or 140% (HIGH)]. At breeding Se treatments were initiated followed by nutritional treatments on d 40 of gestation. At birth, lambs (n = 13, …

Transcriptional Regulation Of The Porcine Type Ii Gnrh Receptor Gene, Vanessa M. Brauer

Department of Animal Science: Dissertations, Theses, and Student Research

The classical mammalian form of gonadotropin releasing hormone (GnRH), GnRH I, is a hypothalamic neuropeptide that functions as a key regulator of reproduction. The interaction between GnRH I and its receptor, GnRH receptor I (GnRHR I), stimulates gonadotropin secretion from the anterior pituitary gland. The gonadotropins, luteinizing hormone (LH) and follicle stimulating hormone (FSH), act on the gonads to stimulate either steroidogenesis and ovulation or gametogenesis, respectively. The steroid hormones produced in the gonads act through a feedback pathway to regulate the production of both GnRH I from the hypothalamus and gonadotropins from the anterior pituitary.

Another form of GnRH, …

Evaluation Of Glyphosate-Tolerant And Conventional Alfalfa Weed Control Systems During The First Year Of Establishment, Robert Wilson Jr., Paul Burgener

Department of Agronomy and Horticulture: Faculty Publications

A field trial was conducted for 3 yr (2005 through 2007) near Scottsbluff, NE, to examine weed control, crop safety, forage production, and economics of glyphosate-tolerant and conventional alfalfa establishment systems. Glyphosate applied to alfalfa at the unifoliate growth stage provided 67% weed control and was similar to imazamox applied at the two-trifoliate leaf stage. Delaying glyphosate application until alfalfa had reached the two-trifoliate growth stage improved weed control to 83%, and weed control was similar to imazamox plus 2,4-DB and imazethapyr plus 2,4-DB. Imazamox and imazethapyr caused minor crop injury, and the addition of bromoxynil or 2,4-DB to both …

Impact Of Empire Expansion On Household Diet: The Inka In Northern Chile’S Atacama Desert, Sheila D. Vinton, Linda Perry, Karl J. Reinhard, Calogero M. Santoro, Isabel Teixeira-Santos

School of Natural Resources: Faculty Publications

The impact of expanding civilization on the health of American indigenous societies has long been studied. Most studies have focused on infections and malnutrition that occurred when less complex societies were incorporated into more complex civilizations. The details of dietary change, however, have rarely been explored. Using the analysis of starch residues recovered from coprolites, here we evaluate the dietary adaptations of indigenous farmers in northern Chile’s Atacama Desert during the time that the Inka Empire incorporated these communities into their economic system. This system has been described as ‘‘complementarity’’ because it involves interaction and trade in goods produced at …

Feeding Ecology Of Arctic-Nesting Sandpipers During Spring Migration Through The Prairie Pothole Region, Jan Eldridge, Gary Krapu, Douglas Johnson

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

We evaluated food habits of 4 species of spring-migrant calidrid sandpipers in the Prairie Pothole Region (PPR) of North Dakota. Sandpipers foraged in several wetland classes and fed primarily on aquatic dipterans, mostly larvae, and the midge family Chironomidae was the primary food eaten. Larger sandpiper species foraged in deeper water and took larger larvae than did smaller sandpipers. The diverse wetland habitats that migrant shorebirds use in the PPR suggest a landscape-level approach be applied to wetland conservation efforts. We recommend that managers use livestock grazing and other tools, where applicable, to keep shallow, freshwater wetlands from becoming choked …

Body Size And Predatory Performance In Wolves: Is Bigger Better?, Daniel R. Macnulty, Douglas W. Smith, L. David Mech, Lynn E. Eberly

United States Geological Survey, Northern Prairie Wildlife Research Center: Publications

Summary

1. Large body size hinders locomotor performance in ways that may lead to trade-offs in predator foraging ability that limit the net predatory benefit of larger size. For example, size-related improvements in handling prey may come at the expense of pursuing prey and thus negate any enhancement in overall predatory performance due to increasing size.

2. This hypothesis was tested with longitudinal data from repeated observations of 94 individually known wolves (Canis lupus) hunting elk (Cervus elaphus) in Yellowstone National Park, USA. Wolf size was estimated from an individually based sex-specific growth model derived from …