Digital Commons Network^™

Discovery And Characterization Of Bukakata Orbivirus (Reoviridae:Orbivirus), A Novel Virus From A Ugandan Bat, Anna C. Fagre, Justin S. Lee, Robert M. Kityo, Nicholas A. Bergren, Eric C. Mossel, Teddy Nakayiki, Betty Nalikka, Luke Nyakarahuka, Amy Gilbert, Julian Kerbis Peterhans, Mary B. Crabtree, Jonathan S. Towner, Brian R. Amman, Tara K. Sealy, Amy J. Schuh, Stuart T. Nichol, Julius J. Lutwama, Barry R. Miller, Rebekah C. Kading

United States Department of Agriculture Wildlife Services: Staff Publications

While serological and virological evidence documents the exposure of bats to medically important arboviruses, their role as reservoirs or amplifying hosts is less well-characterized. We describe a novel orbivirus (Reoviridae:Orbivirus) isolated from an Egyptian fruit bat (Rousettus aegyptiacus leachii) trapped in 2013 in Uganda and named Bukakata orbivirus. This is the fifth orbivirus isolated from a bat, however genetic information had previously only been available for one bat-associated orbivirus. We performed whole-genome sequencing on Bukakata orbivirus and three other bat-associated orbiviruses (Fomede, Ife, and Japanaut) to assess their phylogenetic relationship within the genus Orbivirus …

Non-Native Insects Dominate Daytime Pollination In A High-Elevation Hawaiian Dryland Ecosystem, Clare E. Aslan, Aaron B. Shiels, William Haines, Christina T. Liang

United States Department of Agriculture Wildlife Services: Staff Publications

PREMISE OF THE STUDY: Over one-third of the native flowering plant species in the Hawaiian Islands are listed as federally threatened or endangered. Lack of sufficient pollination could contribute to reductions in populations, reproduction, and genetic diversity among these species but has been little studied.

METHODS: We used systematic observations and manual flower treatments to quantify flower visitation and outcrossing dependency of eight native (including four endangered) plant species in a dryland ecosystem in Hawaii: Argemone glauca, Bidens menziesii, Dubautia linearis, Haplostachys haplostachya, Sida fallax, Silene lanceolata, Stenogyne angustifolia, and Tetramolopium arenarium. …

Machine Learning To Classify Animal Species In Camera Trap Images: Applications In Ecology, Michael A. Tabak, Mohammad S. Norouzzadeh, David W. Wolfson, Steven J. Sweeney, Kurt C. Vercauteren, Nathan P. Snow, Joseph M. Halseth, Paul A. Di Salvo, Jesse S. Lewis, Michael D. White, Ben Teton, James C. Beasley, Peter E. Schlichting, Raoul K. Boughton, Bethany Wight, Eric S. Newkirk, Jacob S. Ivan, Eric A. Odell, Ryan K. Brook, Paul M. Lukacs, Anna K. Moeller, Elizabeth G. Mandeville, Jeff Clune, Ryan S. Miller

United States Department of Agriculture Wildlife Services: Staff Publications

1. Motion-activated cameras (“camera traps”) are increasingly used in ecological and management studies for remotely observing wildlife and are amongst the most powerful tools for wildlife research. However, studies involving camera traps result in millions of images that need to be analysed, typically by visually observing each image, in order to extract data that can be used in ecological analyses.

2. We trained machine learning models using convolutional neural networks with the ResNet-18 architecture and 3,367,383 images to automatically classify wildlife species from camera trap images obtained from five states across the United States. We tested our model on an …

Accounting For Heterogeneous Invasion Rates Reveals Management Impacts On The Spatial Expansion Of An Invasive Species, Kim M. Pepin, David W. Wolfson, Ryan S. Miller, Michael A. Tabak, Nathan P. Snow, Kurt C. Vercauteren, Amy J. Davis

United States Department of Agriculture Wildlife Services: Staff Publications

Success of large-scale control programs for established invasive species is challenging to evaluate because of spatial variability in expansion rates, management techniques, and the strength of management intensity. For a well-established invasive species in the spreading phase of invasion, a useful metric of impact is the magnitude by which control slows the rate of spatial spread. The prevention of spatial spreading likely results in substantial benefits in terms of ecosystem or economic damage that is prevented by an expanding invasive species. To understand how local management actions could impact the spatial spread of an established invasive species, we analyzed distribution …

American White Pelican (Pelecanus Erythrorhynchos) Growth, Nutrition And Immunology, Treena L. Ferguson, Brian J. Rude, D. Tommy King

United States Department of Agriculture Wildlife Services: Staff Publications

Limited information about nutrition exists on American White Pelicans (Pelecanus erythrorhynchos) from hatching to fledging. To detail immunity, metabolism and nutrition of juvenile American White Pelicans, during 22-23 July 2011, 103 samples of regurgitate matter were collected at five Chase Lake, North Dakota, USA, and three Bitter Lake, South Dakota, USA, sub-colonies. Regurgitate sample nutrient content was significantly different for organic matter (P = 0.012), crude protein (P = 0.001), neutral detergent fiber (P = 0.014), acid detergent fiber (P = 0.005) and energy (P = 0.034) between North (n = 5) …

Using Dna To Identify The Source Of Invasive Mongooses, Herpestes Auropunctatus (Carnivora: Herpestidae) Captured On Kaua‘I, Hawaiian Islands, Darren J. Wostenberg, Matthew W. Hopken, Aaron B. Shiels, Antoinette J. Piaggio

United States Department of Agriculture Wildlife Services: Staff Publications

Two small Indian mongooses (Herpestes auropunctatus) were live-captured in 2012 at separate locations on the Hawaiian Island of Kaua'i, which was previously considered to be free of this invasive species. Genotypes from these two individuals were compared to genotypes of H. auropunctatus from the islands of Hawai'i (n =39), O'ahu (n =91), Maui (n = 39), and Moloka'i (n = 19) to determine the island of origin of the Kaua'i individuals. Genotypes were generated from each individual using five microsatellite loci. Genetic clustering was estimated by Bayesian inference of spatial clustering of individuals and …

Cause‐Specific Mortality Of The World’S Terrestrial Vertebrates, Jacob E. Hill, Travis L. Devault, Jerrold L. Belant

United States Department of Agriculture Wildlife Services: Staff Publications

Aim: Vertebrates are declining worldwide, yet a comprehensive examination of the sources of mortality is lacking. We conducted a global synthesis of terrestrial vertebrate cause‐specific mortality to compare the sources of mortality across taxa and determine predictors of susceptibility to these sources of mortality.

Location: Worldwide.

Time period: 1970–2018.

Major taxa studied: Mammals, birds, reptiles and amphibians.

Methods: We searched for studies that used telemetry to determine the cause of death of terrestrial vertebrates. We determined whether each mortality was caused by anthropogenic or natural sources and further classified mortalities within these two categories (e.g. harvest, vehicle collision and predation). …

In Situ Evaluation Of An Automated Aerial Bait Delivery System For Landscape-Scale Control Of Invasive Brown Treesnakes On Guam, Shane Siers, Will Pitt, John Eisemann, Larry Clark, Aaron B. Shiels, C. S. Clark, R. J. Gosnell, M. C. Messaros

United States Department of Agriculture Wildlife Services: Staff Publications

After decades of biodiversity loss and economic burden caused by the brown treesnake invasion on the Pacific island of Guam, relief hovers on the horizon. Previous work by USDA Wildlife Services (WS) and its National Wildlife Research Center (NWRC) demonstrated that brown treesnake numbers in forested habitats can be dramatically suppressed by aerial delivery of dead newborn mouse (DNM) baits treated with 80 mg of acetaminophen. However, manual bait preparation and application is impractical for landscape-scale treatment. WS, NWRC, and the US Department of the Interior have collaborated with Applied Design Corporation to engineer an automated bait manufacturing and delivery …

Mind The Gap: Experimental Tests To Improve Efficacy Of Fladry For Nonlethal Management Of Coyotes, Julie K. Young, John Draper, Stewart Breck

United States Department of Agriculture Wildlife Services: Staff Publications

Coyotes (Canis latrans) are the top predator of livestock in the contiguous United States. Developing more effective nonlethal tools to prevent coyote depredation will facilitate coexistence between livestock producers and coyotes. Fladry is a nonlethal deterrent designed to defend livestock by creating a visual barrier to wolves (C. lupus). Fladry may also be effective with coyotes, but large gap spacing between flags may reduce its efficacy. To address this issue, we performed 2 experiments on captive coyotes using fladry modified to reduce gap spacing at the U.S. Department of Agriculture, Predator Research Facility in Millville, Utah, USA, during 2015–2016 and …

Persistence And Conspecific Observations Improve Problem-Solving Abilities Of Coyotes, Julie K. Young, Laura Touzot, Stacey P. Brummer

United States Department of Agriculture Wildlife Services: Staff Publications

Social learning has important ecological and evolutionary consequences but the role of certain factors, such as social rank, neophobia (i.e., avoidance of novel stimuli), persistence, and task-reward association, remain less understood. We examined the role of these factors in social learning by captive coyotes (Canis latrans) via three studies. Study 1 involved individual animals and eliminated object neophobia by familiarizing the subjects to the testing apparatus prior to testing. Studies 2 and 3 used mated pairs to assess social rank, and included object neophobia, but differed in that study 3 decoupled the food reward from the testing apparatus (i.e., altered …

Movement Responses Inform Effectiveness And Consequences Of Baiting Wild Pigs For Population Control, Nathan P. Snow, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Wild pigs (Sus scrofa) damage agricultural and natural resources throughout their nearly global distribution. Subsequently, population control activities (e.g., trapping, shooting, or toxic baiting) frequently involve the deployment of bait to attract wild pigs. A better understanding of how wild pigs respond to bait sites can help maximize efficiency of baiting programs and identify any potential pitfalls. We examined the movement behaviors of 68 wild pigs during three stages of intensive baiting programs (i.e., 15 days each: prior, during, and post baiting) spread across two distinct study areas in southern and northern Texas, USA. We found that bait sites needed …

What Are The Transmission Mechanisms Of Influenza A Viruses In Wild Mammals?, J. Jeffrey Root

United States Department of Agriculture Wildlife Services: Staff Publications

Some influenza A viruses (IAVs) represent serious potential threats to public and agricultural health, with 3 notable examples from the past decade. During 2009, a novel H1N1 IAV (A[H1N1]pdm09), which was first detected in the United States, spread rapidly throughout many regions of the world. In the United States alone, the Centers for Disease Control and Prevention estimated that >60 million human cases were associated with this emergent and pandemic virus. During 2013, a novel H7N9 avian-origin IAV (Asian lineage avian influenza A[H7N9] virus) was first detected in China. This virus not only cost the poultry industry more than $1 …

Raccoon (Procyon Lotor) Response To Ontario Rabies Vaccine Baits (Onrab) In St. Lawrence County, New York, Usa, Kerri Pedersen, Amy T. Gilbert, Kathleen M. Nelson, Daniel P. Morgan, Amy J. Davis, Kurt C. Vercauteren, Dennis Slate, Richard B. Chipman

United States Department of Agriculture Wildlife Services: Staff Publications

Oral rabies vaccination (ORV) campaigns have been conducted annually in the US over the past two decades to prevent raccoon (Procyon lotor) rabies, which is enzootic along the eastern region of the country from southeastern Canada to Alabama. Because raccoon rabies has been eliminated from neighboring Canadian provinces, continued detection of the variant in the US is of concern due to the potential for infected raccoons to cross the border via the St. Lawrence River. Ontario Rabies Vaccine Baits (ONRAB) containing a live, recombinant human adenovirus expressing the rabies virus glycoprotein have been under experimental use in the …

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 raccoon 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 …

Feral Swine Harming Insular Sea Turtle Reproduction: The Origin, Impacts, Behavior And Elimination Of An Invasive Species, Richard M. Engeman, Robert W. Byrd, Jamie Dozier, Mark A. Mcalister, James O. Edens, Elizabeth M. Kierepka, Timothy J. Smyser, Noel Myers

United States Department of Agriculture Wildlife Services: Staff Publications

Feral swine are among the world's most destructive invasive species wherever they are found, with translocations figuring prominently in their range expansions. In contrast, sea turtles are beloved species that are listed as threatened or endangered throughout the world and are the focus of intense conservation efforts. Nest predation by feral swine severely harms sea turtle reproduction in many locations around the world. Here we quantify and economically assess feral swine nest predation at North Island, South Carolina, an important loggerhead sea turtle nesting beach. Feral swine depredation of North Island sea turtle nests was first detected in 2005, with …

Analysis Of Iophenoxic Acid Analogues In Small Indian Mongoose (Herpestes Auropunctatus) Sera For Use As An Oral Rabies Vaccination Biological Marker, Are R. Berentsen, Robert T. Sugihara, Cynthia G. Payne, Israel Leinbach, Steven F. Volker, Ad Vos, Steffen Ortmann, Amy T. Gilbert

United States Department of Agriculture Wildlife Services: Staff Publications

The small Indian mongoose (Herpestes auropunctatus) is a reservoir of rabies virus (RABV) in Puerto Rico and comprises over 70% of animal rabies cases reported annually. The control of RABV circulation in wildlife reservoirs is typically accomplished by a strategy of oral rabies vaccination (ORV). Currently no wildlife ORV program exists in Puerto Rico. Research into oral rabies vaccines and various bait types for mongooses has been conducted with promising results. Monitoring the success of ORV relies on estimating bait uptake by target species, which typically involves evaluating a change in RABV neutralizing antibodies (RVNA) post vaccination. This …

Trail Cameras Are A Key Monitoring Tool For Determining Target And Non-Target Bait-Take During Rodent Removal Operations: Evidence From Desecheo Island Rat Eradication, Aaron B. Shiels, D. Will, C. Figuerola-Hernández, K.J. Swinnerton, S. Silander, C. Samra, G.W. Witmer

United States Department of Agriculture Wildlife Services: Staff Publications

Efforts to remove invasive rodents (e.g. Rattus spp. and Mus musculus) from islands often use toxicant-laced baits containing the anticoagulants brodifacoum or diphacinone. Rodenticide baits are generally delivered through aerialor hand-broadcast, or in bait stations. These baits are not rodent-specific and are subject to non-target consumption or secondary exposure (e.g. an individual preying upon another individual that has consumed bait). During rodenticide applications, it is generally unknown which animals are visiting and consuming bait; and to quantify this, we recommend using trail cameras (e.g. Reconyx^tm motion-activated infra-red) positioned to monitor individual bait pellets. To demonstrate the importance and effectiveness …

Determination Of Residue Levels Of The Avicide 3-Chloro-4-Methylaniline Hydrochloride In Red-Winged Blackbirds (Agelaius Phoeniceus) By Gas Chromatography-Tandem Mass Spectrometry, David A. Goldade, Kirsten R. Kim, James C. Carlson, Steven F. Volker

United States Department of Agriculture Wildlife Services: Staff Publications

The avicide 3‑chloro‑4‑methylanaline hydrochloride (chloro‑p‑toluidine hydrochloride, CPTH, DRC-1339) is used to control pest bird species that damage agricultural crops. A specific and sensitive gas chromatographytandem mass spectrometry method was developed and validated for the determination of CPTH in avian breast muscle, GI tract, kidney, and liver. Tissue samples were extracted with a solution of acidified water and acetonitrile. The sample was made basic and cleaned up with a combination of liquid-liquid partitioning and solid phase extraction. Separation was achieved using a HP-5 ultra-inert GC column (15 M, 0.25 μm film) with detection on a triple quadrupole mass spectrometer …

Macroeconomic Impact Of Foot‐And‐Mouth Disease Vaccination Strategies For An Outbreak In The Midwestern United States: A Computable General Equilibrium, Maryfrances Miller, Lirong Liu, Steven Shwiff, Stephanie Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

The impacts of alternative responses to a hypothetical foot‐and‐mouth disease (FMD) outbreak occurring in the Midwestern United States are estimated using the Regional Economic Modelling Incorporated Policy Insight + (REMI) computable general equilibrium model, with particular attention paid to the employment impact estimates. The impact on employment and GDP is estimated using forecasts of a 10‐ year period with disease outbreak duration up to 2 years. Fifteen different vaccination protocols are compared to a disease control protocol that relies on animal depopulation with no vaccination. Results show that over the 10‐year study period, the strictly depopulation strategy that made no …

The Intrepid Urban Coyote: A Comparison Of Bold And Exploratory Behavior In Coyotes From Urban And Rural Environments, Stewart W. Breck, Sharon A. Poessel, Peter Mahoney, Julie K. Young

United States Department of Agriculture Wildlife Services: Staff Publications

Coyotes (Canis latrans) are highly adaptable, medium-sized carnivores that now inhabit nearly every large city in the United States and Canada. To help understand how coyotes have adapted to living in urban environments, we compared two ecologically and evolutionarily important behavioral traits (i.e., bold-shy and exploration-avoidance behavior) in two contrasting environments (i.e., rural and urban).

Boldness is an individual’s reaction to a risky situation and exploration is an individual’s willingness to explore novel situations. Our results from both tests indicate that urban coyotes are bolder and more exploratory than rural coyotes and that within both populations there are …

Group Effects Of A Non-Native Plant Invasion On Rodent Abundance, Bryan M. Kluever, Trinity N. Smith, Eric M. Gese

United States Department of Agriculture Wildlife Services: Staff Publications

Cheatgrass (Bromus tectorum) is the most prolific invading plant in western North America. Investigations determining the impact of this invasion on population state variables and community dynamics of rodents have largely occurred at the community or species level, creating a knowledge gap as to whether rodents affiliated by a shared taxonomy or other grouping are differentially affected by cheatgrass invasion. We examined rodent abundance along a gradient of cheatgrass cover using various groupings of two nocturnal rodent taxa comprising the majority of the rodent community in the Great Basin Desert. In the summers of 2010–2013, rodents were sampled …

Parasitism, Host Behavior, And Invasive Species, Sarah N. Bevins

United States Department of Agriculture Wildlife Services: Staff Publications

Animal behavior and parasitism are inextricable linked. In many cases, host behavior can affect what parasites are encountered. In other cases, parasites can manipulate the behavior of the host in an attempt to maximize their own transmission. These long-standing interactions are now further complicated by species movement around the globe. The list of introduced species that have become invasive includes parasites that have adapted to new hosts in areas of introduction, as well as invasive hosts that alter the association between existing parasite–host assemblages. Researchers have documented differences in rates of parasitism and in the consequences of parasite infection between …

The Effect Of High Density Oral Rabies Vaccine Baiting On Rabies Virus Neutralizing Antibody Response In Raccoons (Procyon Lotor), Kerri Pedersen, Amy Gilbert, Eric S. Wilhelm, Kathleen M. Nelson, Amy J. Davis, Jordona D. Kirby, Kurt C. Vercauteren, Shylo Johnson, Richard B. Chipman

United States Department of Agriculture Wildlife Services: Staff Publications

From 2014 to 2016, we examined the effect of distributing oral rabies vaccine baits at high density (150 baits/km2) in an area of Virginia, US that was na¨ıve to oral rabies vaccination prior to the study. We also compared the effect of baiting at high density in a na¨ıve area to baiting at standard density (75 baits/km2) in an area that had been baited annually for 12 yr. Our results suggested that rabies virus seroconversion in raccoons (Procyon lotor) gradually increased each year under the high density bait treatment. However, we did not detect a difference in seroconversion between bait …

Isolation Of Rabies Virus From The Salivary Glands Of Wild And Domestic Carnivores During A Skunk Rabies Epizootic, Cornell University Jimenez, Terry R. Spraker, Jessica Anderson, Richard Bowen, Amy Gilbert

United States Department of Agriculture Wildlife Services: Staff Publications

Rabies is a fatal zoonotic disease of global importance. Rabies virus is shed in the saliva of infected hosts and is primarily transmitted through bite contact. Canine rabies has been eliminated from the US, but wildlife constitutes more than 90% of the reported cases of animal rabies in the US each year. In the US, several wild carnivore species are reservoirs of distinct variants of rabies virus (RV). After decades of apparent absence, the south-central skunk (SCSK) RV variant was detected in Colorado in 2007 and resulted in a large-scale epizootic in striped skunk (Mephitis mephitis) populations in northern Colorado …

Experimental Infections Of Norway Rats With Avian‑Derived Low‑Pathogenic Influenza A Viruses, Kaci K. Vandalen, Nicole M. Nemeth, Nicholas O. Thomas, Nicole L. Barrett, Jeremy W. Ellis, Heather J. Sullivan, Alan B. Franklin, Susan A. Shriner

United States Department of Agriculture Wildlife Services: Staff Publications

Influenza A viruses (IAVs) are a public-health, veterinary, and agricultural concern. Although wild birds are considered the primary reservoir hosts for most IAVs, wild-bird IAV strains are known to spill over into poultry, domestic or wild mammals, and humans. Occasionally, spillover events may result in adaptation or reassortment with other strains. Moreover, some IAV strains found in wild waterfowl mutate into highly pathogenic forms in poultry, causing tremendous economic losses. When domestic animals, wildlife, and humans dwell in close proximity to each other, such as may be the case with agricultural operations, wildlife may represent a potential risk for interspecies …

Predation And Disease-Related Economic Impacts Of Wild Pigs On Livestock Producers In 13 States, Aaron M. Anderson, Chris Slootmaker, Erin Harper, Ryan S. Miller, Stephanie A. Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

We report the results of a survey on wild pigs (Sus scrofa) damage to livestock producers in 13 US states (Alabama, Arkansas, California, Florida, Georgia, Louisiana, Mississippi, Missouri, North Carolina, Oklahoma, South Carolina, Tennessee, Texas). The survey was distributed by the USDA National Agricultural Statistical Service in the summer of 2017 to a sample of livestock producers in the 13-state region. Findings indicate that predation and disease-related damage can be substantial in certain states and for certain types of livestock. In particular, damage to cattle operations in Texas and Arkansas was substantially higher than damage in other states …

Potential Role Of Wildlife In The Usa In The Event Of A Foot-And-Mouth Disease Virus Incursion, Vienna R. Brown, Sarah N. Bevins

United States Department of Agriculture Wildlife Services: Staff Publications

Foot-and-mouth disease (FMD) is caused by foot-and-mouth disease virus (FMDV) which affects domestic and wild cloven-hoofed species. The FMD-free status of the USA and the tremendous economic impact of a virus incursion motivated the development of this evaluation of the potential role of wildlife in the event of a virus introduction. Additionally, this manuscript contains a summary of US vulnerabilities for viral incursion and persistence which focuses specifically on the possible role of wildlife. The legal movement of susceptible live animals, animal products, by-products and animal feed containing animal products pose a risk of virus introduction and spread. Additionally, the …

Reducing Prairie Dog Populations And Damage By Castration Of Dominant Males, Gary W. Witmer

United States Department of Agriculture Wildlife Services: Staff Publications

Black-tailed prairie dogs (Cynomys ludovicianus) occur widely across the prairie states of North America. They compete with livestock for forage, transmit plague, and damage lawns, landscaping, and property. Interest in non-lethal methods, such as immunocontraception, is growing; however, reductions in the population due to contraception may be offset by increases in survival because adults and yearlings are not subject to the energetic demands of reproduction, and lower densities may increase the amount of resources available to growing offspring. Surgical sterilization provides a means for modeling these effects. Thus, we castrated males prior to the 1998 breeding season to simulate the …

The Role Of Scavenging In Disease Dynamics, Joaquín Vicente, Kurt C. Vercauteren

United States Department of Agriculture Wildlife Services: Staff Publications

Contents

Introduction................ 161

The Use of Animal Remains and the Exposure of Scavengers to Disease........ 163

The Relevance of Scavenging for Pathogens to Spread and Persist.......... 166

Human Related Factors Resulting in Increased Risk for Disease Transmission Through Scavenging.............. 170

Management of Scavenging to Reduce Disease Risks.............. 173

Restoration of Large Predators.................. 174

Elimination of Hunting of Scavengers............ 174

Destruction of Big Game and Domestic Animal Carcasses........... 174

Restoration of the Effects of Overabundance............. 175

Excluding Mammalian and Avian Scavengers from Natural Carrions.......... 176

Excluding Mammalian and Avian Scavengers from Vulture Restaurants........... 176

Conclusions and Future Perspectives........... 178

References............... 178

Effects Of Endophyte-Infected Tall Fescue Seed And Red Clover Isoflavones On Rumen Microbial Populations And Physiological Parameters Of Beef Cattle, Emily A. Melchior, Jason K. Smith, Liesel G. Schneider, Travis Mulliniks, Gary E. Bates, Michael D. Flythe, James L. Klotz, Huihua Ji, Jack P. Goodman, Amanda R. Lee, J. Marc Caldwell, Phillip R. Myer

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

Lolium arundinaceum [(Darbyshire) tall fescue] toxicosis is responsible for substantial beef production losses in the United States, due to its negative effects on reproduction, growth, and feed efficiency. These effects are consequences of toxic alkaloids within tall fescue. Interseeding legumes, such as Trifolium pratense (red clover), into pastures has been shown to mitigate a portion of these effects. Clovers contain isoflavones, which may play a role in tall fescue toxicosis mitigation. The present study utilized 36 Angus steers to determine the effects of daily supplementation with a red clover- isolated isoflavone feed additive on physiological symptoms of tall fescue toxicosis …