Veterinary Preventive Medicine, Epidemiology, and Public Health Commons^™

Economic Consequences Of The Wolf Comeback In The Western United States, Dana Hoag, Stewart W. Breck, Kevin Crooks, Becky Niemiec

United States Department of Agriculture Wildlife Services: Staff Publications

Gray wolves were eradicated from most of the United States in the 1940’s but have made a comeback in parts of their historic range over the last two decades. First reintroduced into the Greater Yellowstone Ecosystem and central Idaho in the mid-1990’s, wolves have subsequently dispersed into at least 7 western states. Coloradoans became the latest state to take interest in bolstering wolf populations, as residents passed a ballot initiative in November 2020 to reintroduce a self-sustaining population of gray wolves by the end of 2023. Conflicts between people in rural areas that might incur costs (such as livestock loss) …

Understanding Continent-Wide Variation In Vulture Ranging Behavior To Assess Feasibility Of Vulture Safe Zones In Africa: Challenges And Possibilities, Adam Kane, Ara Monadjem, H. K.Ortwin Aschenborn, Keith Bildstein, André Botha, Claire Bracebridge, Evan R. Buechley, Ralph Buij, John P. Davies, Maria Diekmann, Colleen T. Downs, Nina Farwig, Toby Galligan, Gregory Kaltenecker, Chris Kelly, Ryno Kemp, Holger Kolberg, Monique L. Mackenzie, John Mendelsohn, Msafiri Mgumba, Ran Nathan, Aaron Nicholas, Darcy Ogada, Morgan Pfeiffer, W. Louis Phipps, Matteuns D. Pretorius, Sascha Rösner, Dana G. Schabo, Gabriel Lita Shatumbu, Orr Spiegel, Lindy J. Thompson, Jan A. Venter, Munir Virani, Kerri Wolter, Corinne J. Kendall

United States Department of Agriculture Wildlife Services: Staff Publications

Protected areas are intended as tools in reducing threats to wildlife and preserving habitat for their long-term population persistence. Studies on ranging behavior provide insight into the utility of protected areas. Vultures are one of the fastest declining groups of birds globally and are popular subjects for telemetry studies, but continent-wide studies are lacking. To address how vultures use space and identify the areas and location of possible vulture safe zones, we assess home range size and their overlap with protected areas by species, age, breeding status, season, and region using a large continent-wide telemetry datasets that includes 163 individuals …

European Starling Use Of Nest Boxes Relative To Human Disturbance, Bradley Blackwell, Bruce N. Buckingham, Morgan B. Pfeiffer

United States Department of Agriculture Wildlife Services: Staff Publications

gars and to engine and flight surfaces of moored aircraft. We questioned whether consistent removal of nest material would negatively affect use of a nest site, measured by a reduction in material accumulation. We conducted our study on a 2,200-ha site in Erie County, Ohio, USA (41° 22’ N, 82° 41’ W), from April 15 through June 2, 2020. We used 120 wooden nest boxes on utility poles, protected by an aluminum predator guard below the box. Our treatments included (1) twice weekly, repeated nest material removal (RMR; n = 40 nest boxes); (2) complete nest removal, but only after …

Tick Surveillance And Pathogen Detection In Eastern South Dakota, Holly E. Black

Honors Thesis

Tick-borne diseases threaten the health of humans, animals, and ecosystems, but surveillance efforts are lacking in some regions. Throughout 2019, 2020, and 2021, we conducted tick surveys aimed at determining the status of the black-legged tick (Ixodes scapularis), the American dog tick (Dermacentor variabilis) and the lone star tick (Amblyoma americanum) in eastern South Dakota. Each year, ticks were collected using a flagging method and identified in the lab. A subset were tested for the presence of Borrelia burgdorferi, the causative agent of Lyme disease, by polymerase chain reaction (PCR). Dermacentor variabilis was the most commonly identified tick, …

A Review Of The Impacts Of Invasive Wild Pigs On Native Vertebrates, Matthew T. Mcdonough, Stephen S. Ditchkoff, Mark D. Smith, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

The wild pig (Sus scrofa) is a successful invasive species that has become well established outside of its native range in Eurasia. The invasive wild pig is the result of released or escaped domesticated livestock becoming feral, or Eurasian boar introduced for hunting purposes. The global spread of wild pigs has recently been exacerbated in some areas, such as the USA, by anthropogenically assisted dispersal. Once established in novel ecosystems, wild pigs have the potential to have significant negative impacts on the ecosystem, and the scientific literature is replete with examples. It is generally accepted that wild pigs …

Use Of A Direct, Rapid Immunohistochemical Test For Diagnosis Of Rabies Virus In Bats, Charles E. Rupprecht, Lolita Van Pelt, April D. Davis, Richard B. Chipman, David L. Bergman

United States Department of Agriculture Wildlife Services: Staff Publications

Rabies, a zoonotic encephalitis due to transmission of a lyssavirus, such as rabies virus (RABV), has the highest case fatality of any infectious disease. A global program for the elimination of human rabies caused by dogs is proposed for realization by 2030. Sensitive, specific, and inexpensive diagnostic tests are necessary for enhanced surveillance to detect infection, inform public health and veterinary professionals during risk assessments of exposure, and support overall programmatic goals. Multiple laboratory techniques are used to confirm a suspect case of rabies. One method for the detection of lyssavirus antigens within the brain is the direct rapid immunohistochemical …

Optimizing Management Of Invasions In An Uncertain World Using Dynamic Spatial Models, Kim M. Pepin, Amy J. Davis, Rebecca S. Epanchin-Niell, Andrew M. Gormley, Joslin L. Moore, Timothy J. Smyser, H. Bradley Shaffer, William L. Kendall, Katriona Shea, Michael C. Runge, Sophie Mckee

United States Department of Agriculture Wildlife Services: Staff Publications

Dispersal drives invasion dynamics of nonnative species and pathogens. Applying knowledge of dispersal to optimize the management of invasions can mean the difference between a failed and a successful control program and dramatically improve the return on investment of control efforts. A common approach to identifying optimal management solutions for invasions is to optimize dynamic spatial models that incorporate dispersal. Optimizing these spatial models can be very challenging because the interaction of time, space, and uncertainty rapidly amplifies the number of dimensions being considered. Addressing such problems requires advances in and the integration of techniques from multiple fields, including ecology, …

An Efficient Method Of Evaluating Multiple Concurrent Management Actions On Invasive Populations, Amy J. Davis, Randy Farrar, Brad Jump, Parker Hall, Travis Guerrant, Kim M. Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Evaluating the efficacy of management actions to control invasive species is crucial for maintaining funding and to provide feedback for the continual improvement of management efforts. However, it is often difficult to assess the efficacy of control methods due to limited resources for monitoring. Managers may view effort on monitoring as effort taken away from performing management actions. We developed a method to estimate invasive species abundance, evaluate management effectiveness, and evaluate population growth over time from a combination of removal activities (e.g., trapping, ground shooting) using only data collected during removal efforts (method of removal, date, location, number of …

Economics Of Cormorant Predation On Catfish Farms, Carole Engle, Ganesh Kumar, Terrel Christie, Brian S. Dorr, Brian Davis, Luke Roy, Anita Kelly

United States Department of Agriculture Wildlife Services: Staff Publications

The Double-crested Cormorant is the primary avian predator on catfish farms causing significant economic losses primarily due to 1) on-farm expenditures related to bird-management activities and 2) value of the catfish lost to cormorants. This comprehensive economic study quantified these two economic effects by surveying catfish farms in the delta regions of Mississippi and Arkansas. On-farm expenditures for bird scaring were used to quantify bird-management costs. Economic losses from fish consumed by cormorants were quantified by evaluating data from field studies of the abundance, distribution, and diet of cormorants in the Mississippi delta. This study found that catfish farmers …

No Panacea Attractant For Wild Pigs (Sus Scrofa), But Season And Location Matter, Nathan P. Snow, Caitlin A. Kupferman, Michael J. Lavelle, Kim M. Pepin, Madeline H. Melton, Whitney J. Gann, Kurt C. Vercauteren, James C. Beasley

United States Department of Agriculture Wildlife Services: Staff Publications

Wild pigs (Sus scrofa) are a prolific invasive species throughout many regions of the world that cause extensive economic and environmental damage. Trapping is a common strategy for reducing their populations with baits (i.e., food) and attractants (e.g., scents) used to lure wild pigs into traps. However, there is little information on which scent attractants may attract wild pigs more readily and rapidly across regions and seasons. We examined 60 scent attractants for wild pigs that could be used to increase trapping success across three seasons (winter, spring, and fall) and in two geographic regions, including a warm …

Predation Thresholds For Reintroduction Of Native Avifauna Following Suppression Of Invasive Brown Treesnakes On Guam, Robert M. Mcelderry, Eben H. Paxton, Andre V. Nguyen, Shane R. Siers

United States Department of Agriculture Wildlife Services: Staff Publications

The brown treesnake (BTS) (Boiga irregularis) invasion on Guåhan (in English, Guam) led to the extirpation of nearly all native forest birds. In recent years, methods have been developed to reduce BTS abundance on a landscape scale. To help assess the prospects for the successful reintroduction of native birds to Guåhan following BTS suppression, we modeled bird population persistence based on their life history characteristics and relative sensitivity to BTS predation. We constructed individual-based models and simulated BTS predation in hypothetical founding populations for each of seven candidate bird species. We represented BTS predation risk in two steps: …

Conserving Endangered Black-Footed Ferrets: Biological Threats, Political Challenges, And Lessons Learned, Travis M. Livieri, Steven C. Forrest, Marc R. Matchett, Stewart Breck

United States Department of Agriculture Wildlife Services: Staff Publications

There may be few stories in the annals of wildlife management that are as dramatic as the near demise and comeback of the black-footed ferret (Mustela nigripes). Endemic only to North America, this charming little carnivore found only in the continent’s central grasslands was hardly known to science until the mid-20th century. By then, vast colonies of the prey it depended on for food and shelter, the prairie dog (Cynomys spp.), had been wiped out through disease (sylvatic plague) and an agricultural industry with little tolerance for burrowing and grazing rodents. At its low point, the species’ …

Beef Quality Following Prolonged Aging After Supplementing High Levels Of Vitamin E, Nicolas J. Herrera, Joseph A. Sonderman, David M. Velazco, Chris Calkins

Nebraska Beef Cattle Reports

Increased postmortem aging of beef can accelerate discoloration, shortening retail display time, inducing oxidation of lipids and proteins, and generating negative flavor attributes. This study was conducted to evaluate supplementation of high levels (2,200 International Units/head/day for 100 d) of Vitamin E (α-tocopherol) when feeding cattle as a strategy to sustain meat color quality in beef strip loins after prolonged aging. Results showed significantly less discoloration in loins from animals fed high levels of Vitamin E across 3, 6, and 9 weeks of aging. In addition, loins from cattle fed high levels of Vitamin E exhibited significantly greater redness (a*) …

2022 Nebraska Beef Cattle Report

Nebraska Beef Cattle Reports

The purpose of beef cattle and beef product research at the University of Nebraska-Lincoln is to provide reference information that represents the various populations (cows, calves, heifers, feeders, carcasses, retail products, etc.) of beef production.

Dedicated in memory of Dr. Terry Klopfenstein (March 10, 1939-April 30, 2021), Professor Emeritus, Animal Science Department, University of Nebraska-Lincoln.

Cow-Calf Nutrition and Management

Impact of Cow Size on Economic Profitability in the Cow-Calf and Feedlot Production Systems

Comparison of Partially Confined and Traditional Cow-Calf Systems

Concepts in Stress Physiology

Inflammatory Modulators Improve Daily Gain of Heat-Stressed Wethers

Zilpaterol Supplementation Improved Indicators of Well-Being, but …

Fate Of Salmonella In Beef Steaks During Sous Vide Cooking, Heather B. Hunt, Samuel C. Watson, Byron D. Chaves, Gary Sullivan

Nebraska Beef Cattle Reports

Sous vide cooking meat products has become a popular in-home method of food preparation. Previous research from UNL Meat Science using generic E. coli demonstrated the potential risk of sous vide cooking at temperatures recommended by some popular press items. To increase the understanding of the safety concerns of cooking beef products to temperatures below USDA-Food Safety and Inspection Service (FSIS) guidance temperatures, the experiment was conducted with Salmonella. Steaks were internally inoculated with three serovars of Salmonella, and sous vide cooked to internal temperatures of 115, 125, and 130° F. At least a 5 log₁₀ reduction was achieved …

Effects Of Lime Amendment On Antibiotic Resistance In Beef Cattle Manure Of Open Feedlots, Noelle A. Mware, Galen E. Erickson, Amy Schmidt, Shannon L. Bartelt-Hunt, Xu Li

Nebraska Beef Cattle Reports

The objective of this study was to evaluate the effectiveness of lime amendment on the reduction of antimicrobial resistant bacteria and antimicrobial resistance genes in beef cattle manure in open feedlots. Hydrated lime was uniformly applied to the surface of feedlot pen floor 1 day prior to cattle harvest at a rate of 0.36 lb/ft² and samples were collected over time. Collected samples were analyzed for change in pH and levels of antimicrobial resistant bacteria and antimicrobial resistance genes. Lime amendment elevated the pH of pen floor surface materials to pH > 12 for 4 hours and then pH > 11 …

Impact Of Spring Corn Residue Grazing On Soil Physical Properties And Crop Yield, Morgan T. Grabau, J. C. Macdonald, Zachary E. Carlson, M. E. Drewnoski

Nebraska Beef Cattle Reports

The effects of stocking density for spring corn residue grazing on soil physical properties and soybean yield were evaluated in an experiment with three treatments: no grazing, normal density, and high density. Normal density was stocked at 3 calves/acre and grazed 45 days starting in mid-February. High-density was stocked at 9 calves/acre and grazed 15 days starting in mid-March. Increased stocking density decreased residue cover and increased surface roughness. Bulk density and penetration resistance were increased for normal density compared to no graze, with no difference between grazed treatments, illustrating that grazing may cause minor compaction, regardless of stocking density. …

Evaluation Of Methane And Co2 Production In Growing And Finishing Cattle Raised In Conventional Or Partial Confinement-Based Herds, L. J. Mcphillips, Z. E. Carlson, Rick R. Stowell, J. C. Macdonald, Andrew E. Suyker, Galen E. Erickson

Nebraska Beef Cattle Reports

Methane emissions from growing and finishing calves compared either a spring calving, conventional cow system or a summer calving, partially-confined cow system. Calves weaned from the confinement-based production system were smaller at weaning and compensated with greater gain during the growing phase. More days on feed in the finishing phase were needed for the calves from the confinement system to reach same backfat thickness. Over the entire growing and finishing phases, calves from the confinement-based system produced more total CH₄ and CH₄ per lb. HCW. Production of methane and CO₂ per lb. of gain was lower in …

Impact Of Biochar Supplementation In Finishing Diets On Greenhouse Gas Emissions, J. L. Sperber, Braden C. Troyer, Mitchell M. Norman, Levi J. Mcphillips, Heather Nobert, Andrea K. Watson, Galen E. Erickson

Nebraska Beef Cattle Reports

A study was conducted to evaluate the impact of feeding biochar in a finishing diet on cattle performance, methane and carbon dioxide emissions, and carcass characteristics. Two treatments were evaluated, a high-concentrate control diet without biochar and a diet with biochar included at 1.0% of the diet dry matter, replacing high moisture corn in the diet. Pens of cattle were rotated through a two-sided emissions barn (2 pens evaluated simultaneously) to capture CH4 and CO2 production. There were no statistical differences in gas emissions for biochar supplemented steers compared to control. There was a 2.4% decrease in dry matter intake …

Impact Of A Natural Feed Additive Using Direct Fed Microbes On Finishing Beef Cattle Performance And Liver Abscess Rate, Kelton C. Adair, Alison C. Bartenslager, Zachary E. Carlson, Galen E. Erickson, Samodha C. Fernando, J. C. Macdonald

Nebraska Beef Cattle Reports

A feedlot study with individually fed steers (n=60) was conducted comparing a natural feed additive (Direct Fed Microbial) to no feed additive (control) on performance and liver abscess rate of finishing beef cattle. There were no significant differences between treatments on intake, gain, feed conversion, or hot carcass weight and carcass traits. Liver abscess occurrence and severity were similar for both treatments with 4/29 steers having abscessed livers in the control group and 3/29 steers in the group that received direct fed microbials. The direct fed microbial feed additive fed in this exploratory study did not significantly affect performance, liver …

Evaluation Of Processing Technique For High-Moisture And Dry Corn On Nutrient Digestion When Fed To Finishing Cattle, Caitlin A. Coulson, Mitch M. Norman, Nicole M. Woita, Hannah C. Wilson, Kylie M. Butterfield, Tyler J. Spore, Galen E. Erickson

Nebraska Beef Cattle Reports

A digestion trial was conducted to determine the effect of corn milling method when processing dry or high-moisture corn on nutrient digestion. Treatments were evaluated as a 2 × 2 factorial with the first factor as corn type [dry corn or high-moisture corn] and second factor as mill type [roller mill or hammer mill]. Feeding high-moisture corn decreased the amount of excreted dry matter and organic matter regardless of processing method, but there tended to be an interaction between corn type and milling method for digestibility. There was no difference between milling treatments fed as high-moisture corn, but hammer milled …

Impact Of Steam-Flaked Rye Fed In Combination With Steam-Flaked Corn On Performance And Carcass Characteristics Of Yearling Steers, Samantha K. Wagner, Braden T. Troyer, Levi J. Mcphillips, Rebecca S. Brattain, Galen E. Erickson

Nebraska Beef Cattle Reports

A finishing study evaluated the effect of feeding steam-flaked rye on performance and carcass characteristics of yearling steers. Treatments consisted of different ratios of steam-flaked rye to steam-flaked corn. The ratios were 0:100, 25:75, 50:50, and 100:0 rye:corn. Increasing inclusions of rye linearly decreased final body weight, dry matter intake, average daily gain, and hot carcass weight. As a result, feed conversion was poorer as rye replaced corn. Carcass characteristics reflected lower gain with linear decreases in marbling score, ribeye area, and backfat thickness. There was no difference in yield grade among treatments. Based on dietary energy calculated from performance, …

Evaluating Performance Of Cattle Fed Steam-Flaked Corn Based Finishing Diets Fed Increasing Inclusions Of Wet Or Modified Distillers Grains, Braden C. Troyer, Levi J. Mcphillips, Mitchell M. Norman, Galen E. Erickson

Nebraska Beef Cattle Reports

A finishing trial using 560 calf-fed steers was conducted to evaluate the effect of distillers type and inclusion on finishing cattle performance and carcass characteristics in steam-flaked corn based diets. Treatments were applied in a 2 × 3 + 1 factorial arrangement, with the first factor being distillers type (modified distillers grains plus solubles or wet distillers grains plus solubles) and the second factor being distillers grains inclusion of 10%, 20%, or 30%, as well as a control diet containing no distillers. There was an interaction between inclusion and type of distillers for feed conversion. A linear improvement in feed …

Effect Of Finishing Cattle With Blends Of High Moisture And Steam-Flaked Corn With And Without Distillers Grains, Braden C. Troyer, Zac C. Carlson, Levi J. Mcphillips, Mitchell M. Norman, Andrea K. Watson, J. C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

The objective of this study was to determine the impacts of feeding different ratios of high-moisture corn and steam-flaked corn in diets with or without distillers grains and test for an associative effect between grain processing methods. Steers (n=120; BW=775 ± 15.6 lb) were assigned randomly to one of 8 diets. Diets tested included 100:0, 75:25, 50:50, 25:75, and 0:100 of high-moisture corn:steam-flaked corn in diets with 20% modified distillers grains or 100:0, 50:50, and 0:100 in diets without distillers grains. There was an interaction observed for average daily gain as gain improved in 50:50 blends of HMC:SFC in diets …

Characterizing Digestion Traits Of Novel Corn Bran Products, Jiehua Xiong, Chanon Suntara, Rebecca Sjostrand, Tyler Spore, Maggie Youngers, Rick Stock, Galen E. Erickson, J. C. Macdonald

Nebraska Beef Cattle Reports

A digestion study was conducted to evaluate novel corn bran products from Cargill Corn Milling on nutrient digestibility in beef steers. Three bran products (Bran A/B/C) were included at 70% of diet dry matter of TRT A, B and C, with an internal control (SFC control) diet which consisted of 70% SFC. The SFC control exhibited the greatest dry matter (DM), organic matter (OM) and starch digestibility, and the least neutral detergent fiber (NDF) digestibility. Among TRT A, B and C when bran products were included at 70%, there was no difference in DM or OM intake and digestibility. NDF …

Interaction Of Sweet Bran Inclusion And Corn Processing Method In Beef Finishing Diets On Digestibility, Rebecca L. Sjostrand, Kathlyn Hauxwell, Maggie Youngers, Rick Stock, J. C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

Six ruminally and duodenally fistulated steers were utilized in a 6 × 6 Latin square design to evaluate the interaction of corn processing method and Sweet Bran inclusion in finishing diets on total tract digestibility and rumen fermentation characteristics. Treatments were designed as a 2 × 3 factorial, with one factor as corn processing method (steam-flaked corn or a blend of high-moisture and dry-rolled corn) and the second factor as Sweet Bran inclusion at 0, 20, or 40% of diet dry matter. Cattle fed steam-flaked corn diets had greater starch digestibility while cattle fed high-moisture/ dry-rolled corn diets had greater …

Evaluation Of Models To Predict Dry Matter Intake Of Forage Based Diets, Aksel Wiseman, Andrea K. Watson, Rick Stock, Terry Klopfenstein

Nebraska Beef Cattle Reports

Dry matter intake (DMI) data from growing cattle experiments at the Eastern Nebraska Research and Extension Center were summarized in order to evaluate the accuracy of model predicted DMI. Cattle were fed individually (n = 78) or in pens (n = 15) and predicted DMI using the Beef Cattle Nutrient Requirements Model (BCNRM, 2016) was compared to observed DMI. The model over predicted DMI when total digestible nutrients (TDN) was less than 64%, under predicted DMI when dietary TDN was greater than 64%, and had a low accuracy, explaining less than 22% of the variation in DMI. An equation to …

Interaction Of Urea With Frequency And Amount Of Distillers Grains Supplementation For Growing Steers, Haley F. Linder, Zachary E. Carlson, M. E. Drewnoski, J. C. Macdonald

Nebraska Beef Cattle Reports

A study was conducted to determine the interaction of urea with the frequency and amount of distillers grain supplementation for growing steers consuming forage. Steers were individually fed for 84 d and received ad libitum grass hay and 1 of 8 treatments. Treatment design was a 2 × 2 × 2 factorial. Supplement was fed either every day or 3x/ week, amount of supplement fed was 13.99 lb/week or 28.00 lb/week, and contained either no urea or 1.3% urea. Supplementation frequency and the inclusion of urea did not impact steer average daily gain. The amount of supplement did impacted steer …

Impact Of Urea On Corn Silage Growing Cattle Diets, Tyler J. Spore, Hannah C. Wilson, Nolan R. Meier, Galen E. Erickson, James C. Macdonald, Terry J. Klopfenstein, Andrea K. Watson

Nebraska Beef Cattle Reports

Two experiments were conducted to evaluate the effects of increasing urea in a corn silage growing cattle diet and ensiling time impact on rumen undegradable protein content of corn silage. Four treatments (urea inclusion at 0, 0.5, 1, and 1.5% of diet dry matter) were evaluated in diets containing 95% corn silage using 10 ruminally and duodenally cannulated heifers. Corn silage was sampled 5 times (every 32 days) to determine rumen undegradable protein content. Intake and total tract digestibility of dry matter, organic matter, and neutral detergent fiber all increased linearly with increasing inclusion of urea in the diet. Measured …

Growth Performance In Livestock With Stress-Induced Low Birthweight Is Recovered By Clenbuterol Administration, Rachel L. Gibbs, Rebecca M. Swanson, Joslyn K. Beard, Ty B. Schmidt, Jessica Lynn Petersen, Dustin T. Yates

Nebraska Beef Cattle Reports

Stress in pregnant livestock causes pathological low birthweight of the offspring and diminishes their muscle growth capacity. Using sheep as a model for beef cattle, this study determined that the limited growth capacity of offspring with stress-induced low birthweight could be recovered by postnatal treatments. Muscle in these animals has less growth-promoting β2 adrenergic activity and thus the injectable β2 adrenergic stimulant clenbuterol was used as a daily treatment. Lambs with stress-induced low birthweight continued to exhibit impaired muscle growth and feed efficiency well past the normal age for weaning. In addition, they began to put on excess fat around …