Other Veterinary Medicine Commons^™

Investigation Of Nile Tilapia Mortalities During Summer 2019 In El-Manzala Fish Farms In Dakahlia Governorate, Egypt, Amira M. M. El- Sherbiny, Moustafa M. S. Fouda, Medhat S. Shakweer, Viola H. Zaki

Mansoura Veterinary Medical Journal

Objective: To identify suspected causes of mass mortality in Oreochromis niloticus at El-Manzala fish farms in Dakahlia Governorate, Egypt, during disease outbreaks in the summer of 2019.

Design: Observational study.

Animals: Two hundred diseased and freshly dead Oreochromis niloticus (Nile tilapia) weighting 100-150 g.

Procedures: Collected fish samples were subjected to clinical, postmortem and bacteriological investigations regarding histopathological alterations, pathogenicity tests, and antibiogram susceptibility of the main isolated bacterial species.

Results: A total of 286 bacterial isolates were detected from all examined fish samples. Bacteriological examination revealed that all bacteria were gram-negative rods, which were identified as A. hydrophila (43.36%), …

Interspecific Oral Rabies Vaccine Bait Competition In The Southeast United States, Wesley C. Dixon, Jacob E. Hill, Richard Chipman, Amy J. Davis, Amy Gilbert, James C. Beasley, Olin E. Rhodes Jr., Guha Dharmarajan

United States Department of Agriculture Wildlife Services: Staff Publications

The United States Department of Agriculture’s National Rabies Management Program (NRMP) has coordinated the use of oral rabies vaccination (ORV) to control the spread of raccoon rabies virus variant west of the Appalachian Mountains since 1997. Working with state and local partners, the NRMP deploys ORV baits containing a rabies vaccine, primarily targeting raccoon populations (Procyon lotor). Bait competition between raccoons and non-target species may limit the effectiveness of ORV programs, but the extent of bait competition remains poorly quantified, particularly in the southeastern United States. We placed placebo ORV baits in bottomland hardwood (n = 637 baits) and upland …

Straight From The Coyote’S Mouth: Genetic Identification Of Prey Through Oral Swabs Of Predators, Julie K. Young, Amanda M. Mast, James A. Walton, Torrey Rodgers, Antionette J. Piaggio, Daniel R. Taylor, Karen E. Mock

United States Department of Agriculture Wildlife Services: Staff Publications

Human-carnivore conflicts often involve the depredation of domestic livestock. These depredation events are rarely observed, yet mitigation typically involves identifying the species or individual involved for removal or relocation. We tested a molecular method to identify individuals involved in depredation events using mouth swabs to determine if prey DNA could be detected, and for how long. We fed mule deer Odocoileus hemionus meat to captive coyotes Canis latrans and swabbed their mouths at five predetermined intervals between 2–72 h after consumption of the deer meat. We assessed two different molecular forensic methods to analyze the saliva swabs: qPCR for species …

Movements And Resource Selection Of Wild Pigs Associated With Growth Stages Of Corn, Bethany A. Friesenhahn, Randall W. Deyoung, Michael J. Cherry, Humberto L. Perotto-Baldivieso, Kurt C. Vercauteren, Nathan P. Snow

United States Department of Agriculture Wildlife Services: Staff Publications

Wild pigs (Sus scrofa) are one of the most successful invasive species globally and are often implicated in agricultural damage. This damage is expected to increase as ranges of wild pigs expand, impacting the human food supply and increasing costs of food production. Our objective was to evaluate movement behaviors of wild pigs relative to resource availability and landscape features in an agriculture-dominated landscape, with a goal of informing management practices for reducing damage to corn. We monitored hourly movements of adult wild pigs relative to corn crops using GPS collars during the 2019 and 2020 growing seasons (Feb–Sept) in …

Burmese Pythons In Florida: A Synthesis Of Biology, Impacts, And Management Tools, Jacquelyn C. Guzy, Bryan G. Falk, Brian J. Smith, John David Willson, Robert N. Reed, Nicholas G. Aumen, Michael L. Avery, Ian A. Bartoszek, Earl Campbell, Michael S. Cherkiss, Natalie M. Claunch, Andrea F. Currylow, Tylan Dean, Jeremy Dixon, Richard Engeman, Sarah Funck, Rebekah Gibble, Kodiak C. Hengstebeck, John S. Humphrey, Margaret E. Hunter, Jillian M. Josimovich, Jennifer Ketterlin, Michael Kirkland, Frank J. Mazzotti, Robert Mccleery, Melissa A. Miller, Matthew Mccollister, M. Rockwell Parker, Shannon E. Pittman, Michael Rochford, Christina Romagosa, Art Roybal, Ray W. Snow, Mckayla M. Spencer, J. Hardin Waddle, Any A. Yackel Adams, Kristen M. Hart

United States Department of Agriculture Wildlife Services: Staff Publications

Burmese pythons (Python molurus bivittatus) are native to southeastern Asia, however, there is an established invasive population inhabiting much of southern Florida throughout the Greater Everglades Ecosystem. Pythons have severely impacted native species and ecosystems in Florida and represent one of the most intractable invasive-species management issues across the globe. The difficulty stems from a unique combination of inaccessible habitat and the cryptic and resilient nature of pythons that thrive in the subtropical environment of southern Florida, rendering them extremely challenging to detect. Here we provide a comprehensive review and synthesis of the science relevant to managing invasive …

Effects Of Corn Supplementation On Serum And Muscle Microrna Profiles In Horses, Clarissa Carver, Jason E. Bruemmer, Stephen Coleman, Gabriele Landolt, Tanja Hess

United States Department of Agriculture Wildlife Services: Staff Publications

Laminitis associated with equine metabolic syndrome causes significant economic losses in the equine industry. Diets high in non-structural carbohydrates (NSC) have been linked to insulin resistance and laminitis in horses. Nutrigenomic studies analyzing the interaction of diets high in NSCs and gene expression regulating endogenous microRNAs (miRNA) are rare. This study's objectives were to determine whether miRNAs from dietary corn can be detected in equine serum and muscle and its impacts on endogenous miRNA. Twelve mares were blocked by age, body condition score, and weight and assigned to a control (mixed legume grass hay diet) and a mixed legume hay …

Using Drones To Detect And Quantify Wild Pig Damage And Yield Loss In Corn Fields Throughout Plant Growth Stages, Bethany A. Friesenhahn, Lori D. Massey, Randy W. Deyoung, Michael J. Cherry, Justin W. Fischer, Nathan P. Snow, Kurt C. Vercauteren, Humberto L. Perotto‐Baldivieso

United States Department of Agriculture Wildlife Services: Staff Publications

Presently, there are an estimated 6.9 million wild pigs (Sus scrofa) in the U.S., which cause over US$1 billion in damage to agriculture, environmental impacts, and control costs. However, estimates of damage have varied widely, creating a need for standardized monitoring and a method to accurately estimate the economic costs of direct wild pig damage to agriculture. The goal of our study was to integrate remotely sensed imagery from drones and crop harvest data to quantify wild pig damage in corn fields. We used drones with natural color (red, green, blue) cameras to monitor corn fields at different …

Intracellular Diversity Of Wnv Within Circulating Avian Peripheral Blood Mononuclear Cells Reveals Host-Dependent Patterns Of Polyinfection, Dalit Talmi-Frank, Alex D. Byas, Reyes Murrieta, James Weger-Lucarelli, Claudia Rückert, Emily N. Gallichotte, Janna A. Yoshimoto, Chris Allen, Angela M. Bosco-Lauth, Barbara Graham, Todd A. Felix, Aaron C. Brault, Gregory D. Ebel

United States Department of Agriculture Wildlife Services: Staff Publications

Arthropod-borne virus (arbovirus) populations exist as mutant swarms that are maintained between arthropods and vertebrates. West Nile virus (WNV) population dynamics are host-dependent. In American crows, purifying selection is weak and population diversity is high compared to American robins, which have 100- to 1000-fold lower viremia. WNV passed in robins leads to fitness gains, whereas that passed in crows does not. Therefore, we tested the hypothesis that high crow viremia allows for higher genetic diversity within individual avian peripheral blood mononuclear cells (PBMCs), reasoning that this could have produced the previously observed hostspecific differences in genetic diversity and fitness. Specifically, …

Investigating Nocturnal Uas Treatments In An Applied Context To Prevent Gulls From Nesting On Rooftops, Morgan Pfeiffer, Craig K. Pullins, Scott F. Beckerman, Joshua L. Hoblet, Brad Blackwell

United States Department of Agriculture Wildlife Services: Staff Publications

Ring‐billed (Larus delawarensis) and herring (L. argentatus) gulls are numerous and widespread in North America. These gulls rank among the top 9 species for risk of bird‐aircraft collisions (hereafter strikes). The ubiquitous presence of gulls in urban coastal environments, including rooftop nesting behavior, are factors impacting strike risk. Our purpose was to assess gull response to a small uncrewed aircraft system (UAS) in hazing flights at night during the nest‐building phase. We hypothesized that nocturnal UAS operation, like nocturnal predator disturbance, might reduce gull numbers and, thus, strike risk to aircraft. In spring 2021, we conducted …

Urbanization Influences Spatiotemporal Patterns Of Roost Site Selection By Black Vultures And Turkey Vultures, Jacob E. Hill, Kenneth F. Kellner, Amanda E. Holland, Bryan M. Kluever, Morgan B. Pfeiffer, Travis L. Devault, Jerrold L. Belant

United States Department of Agriculture Wildlife Services: Staff Publications

Roost locations can be an important contributor to vulture conflicts with humans, but factors influencing roost-site selection at a landscape level remain largely unexplored. Further, there has been little research comparing how these factors vary between nocturnal and diurnal roosting sites. We used remote cameras to document daily variation in vulture use of 21 roosts (20 communication/water towers and 1 natural roost) near Beaufort, South Carolina, USA from October 2019–August 2020. Numbers of vultures on roosts increased with decreasing urban cover and with greater distance to water, but were not influenced by habitat fragmentation or elevation. Roosts surrounded by greater …

Defining County-Level Terrestrial Rabies Freedom Using The Us National Rabies Surveillance System: Surveillance Data Analysis, Amber Kunkel, Gabriella Veytsel, Sarah C. Bonaparte, Haillie Meek, Xiaoyue Ma, Amy J. Davis, Jesse Bonwitt, Ryan M. Wallace

United States Department of Agriculture Wildlife Services: Staff Publications

Background: Rabies is a deadly zoonotic disease with nearly 100% fatality rate. In the United States, rabies virus persists in wildlife reservoirs, with occasional spillover into humans and domestic animals. The distribution of reservoir hosts in US counties plays an important role in public health decision-making, including the recommendation of lifesaving postexposure prophylaxis upon suspected rabies exposures. Furthermore, in surveillance data, it is difficult to discern whether counties have no cases reported because rabies was not present or because counties have an unreported rabies presence. These epizootics are monitored by the National Rabies Surveillance System (NRSS), to which approximately 130 …

Deriving Spatially Explicit Direct And Indirect Interaction Networks From Animal Movement Data, Anni Yang, Mark Q. Wilber, Kezia R. Manlove, Ryan S. Miller, Raoul Boughton, James Beasley, Joseph Northrup, Kurt C. Vercauteren, George Wittemyer, Kim Pepin

United States Department of Agriculture Wildlife Services: Staff Publications

Quantifying spatiotemporally explicit interactions within animal populations facilitates the understanding of social structure and its relationship with ecological processes. Data from animal tracking technologies (Global Positioning Systems [“GPS”]) can circumvent longstanding challenges in the estimation of spatiotemporally explicit interactions, but the discrete nature and coarse temporal resolution of data mean that ephemeral interactions that occur between consecutive GPS locations go undetected. Here, we developed a method to quantify individual and spatial patterns of interaction using continuous-time movement models (CTMMs) fit to GPS tracking data. We first applied CTMMs to infer the full movement trajectories at an arbitrarily fine temporal scale …

Long Term Changes In Aquaculture Influence Migration, Regional Abundance, And Distribution Of An Avian Species, Paul C. Burr, Brian S. Dorr, Jimmy L. Avery, Garrett M. Street, Bronson K. Strickland

United States Department of Agriculture Wildlife Services: Staff Publications

Agricultural development has been causing changes to the environment and the abundance and distribution of avian species. Agriculture is dynamic with changes in products occurring at large scales over relatively short time periods. The catfish aquaculture industry is one such agriculture industry that has undergone dramatic changes over the last 25 years. The double-crested cormorant (Nannopterum auritum) is a piscivorous bird that has an extensive history with the aquaculture industry of Mississippi due to its depredation of cultured catfish. A large-scale monitoring program began in 1989 to estimate the abundance and location of cormorants at every known roost in the …

Raccoon Rabies Control And Elimination In The Northeastern Usa And Southern Québec, Canada, Amy J. Davis, Marianne Gagnier, Ariane Massé, Kathleen M. Nelson, Jordona D. Kirby, Ryan Wallace, Xiaoyue Ma, Christine Fehlner-Gardiner, Richard B. Chipman, Amy Gilbert

United States Department of Agriculture Wildlife Services: Staff Publications

Rabies virus (RABV) is a deadly zoonosis that circulates in wild carnivore populations in North America. Intensive management within the USA and Canada has been conducted to control the spread of the raccoon (Procyon lotor) variant of RABV and work towards elimination. We examined RABV occurrence across the northeastern USA and southeastern Québec, Canada during 2008–2018 using a multi-method, dynamic occupancy model. Using a 10 km× 10 km grid overlaid on the landscape, we examined the probability that a grid cell was occupied with RABV and relationships with management activities (oral rabies vaccination (ORV) and trap-vaccinate-release efforts), habitat, neighbour effects …

Validation Of A Nutria (Myocastor Coypus) Environmental Dna Assay Highlights Considerations For Sampling Methodology, Anna M. Mangan, John A. Kronenberger, Ian H. Plummer

United States Department of Agriculture Wildlife Services: Staff Publications

Nutria (Myocastor coypus) is a semiaquatic rodent species that is invasive across multiple regions within the United States. Here, we evaluated a qPCR assay previously described for use in Japan for application across invasive populations in the United States. We also compared two environmental DNA sampling methodologies for this assay: field filtration of large volumes of water passed through filters versus direct sampling of small volumes of water. We validated assay specificity, generality, and sensitivity, compared assay performance between two independent laboratories, and successfully tested the assay in situ on a known wild population. The filtration method required …

Producers’ Perceptions Of Large Carnivores And Nonlethal Methods To Protect Livestock From Depredation: Findings From A Multistate Federal Initiative, Keith M. Carlisle, Hailey E. Ellis, Colorado State University, Alan D. Bright

United States Department of Agriculture Wildlife Services: Staff Publications

We examined livestock producers’ perceptions of wolves, grizzly bears, black bears, and mountain lions, as well as their experiences with using nonlethal methods to protect livestock from depredation. All producers in the study received nonlethal predator management assistance in 2020 from USDA-APHIS-Wildlife Services (“WS”) pursuant to a federally funded initiative focused on the use of nonlethal methods to protect livestock. Such methods included assistance from range riders (i.e., individuals who monitor livestock and carnivores), fladry (i.e., flags hung from rope that serve as a repellent), and other audio/visual deterrents (e.g., Foxlights). The producers did not specifically seek nonlethal assistance from …

Distribution Of Baylisascaris Procyonis In Raccoons (Procyon Lotor) In Florida, Usa, Mark W. Cunningham, Daniel P. Wolf, Katherine A. Sayler, Michael Milleson, Brittany Bankovich, Paul Schueller, Betsy S. Haley, Savannah Stura, Michael J. Yabsley

United States Department of Agriculture Wildlife Services: Staff Publications

Baylisascaris procyonis, or raccoon roundworm, is an intestinal nematode parasite of raccoons (Procyon lotor) that is important to public and wildlife health. Historically, the parasite was uncommon in the southeastern US; however, the range of B. procyonis has expanded to include Florida, US. From 2010 to 2016, we opportunistically sampled 1,030 raccoons statewide. The overall prevalence was 3.7% (95% confidence interval=2.5–4.8%) of sampled individuals, and infection intensity ranged from 1 to 48 (mean±standard deviation 9.9±4.0). We found raccoon roundworm in 9/56 (16%) counties sampled, and the percent positive ranged from 1.1% to 13.3% of specimens collected per …

An Ode To Owls: Review Of What An Owl Knows: The New Science Of The World’S Most Enigmatic Birds By Jennifer Ackerman, Alan B. Franklin

United States Department of Agriculture Wildlife Services: Staff Publications

Owls are mysterious creatures, mainly because we humans hardly ever encounter them. They are mostly nocturnal, are silent in their flight, and tend to unnerve us with their ghostly and sometimes quavering vocalizations. There have been numerous books on the natural history of owls written for nonexperts, but Jennifer Ackerman’s What an Owl Knows takes a novel tack, blending natural history and scientific discovery with a discussion of recent technological innovations. The result is a fascinating read on how scientists are beginning to better understand the lives and ecology of these secretive and rarely visible birds.

The book’s nine chapters …

Tourism‑Supported Working Lands Sustain A Growing Jaguar Population In The Colombian Llanos, Matthew Hyde, Esteban Payán, Jorge Barragan, Diana Stasiukynas, Sanmantha Rincón, William L. Kendall, Jerónimo Rodríguez, Kevin R. Crooks, Stewart W. Breck, Valerie Boron

United States Department of Agriculture Wildlife Services: Staff Publications

Understanding large carnivore demography on human-dominated lands is a priority to inform conservation strategies, yet few studies examine long-term trends. Jaguars (Panthera onca) are one such species whose population trends and survival rates remain unknown across working lands. We integrated nine years of camera trap data and tourist photos to estimate jaguar density, survival, abundance, and probability of tourist sightings on a working ranch and tourism destination in Colombia. We found that abundance increased from five individuals in 2014 to 28 in 2022, and density increased from 1.88 ± 0.87 per 100 km² in 2014 to 3.80 …

Science‐Driven Guidelines Needed To Better Manage And Conserve Black Vultures In North America, Scott A. Rush, Neil J. Buckley, Patrick A. Zollner, Bryan M. Kluever, Brooke Mcwherter, Grant C. Burcham, Zhao Ma, Marian L. Wahl, Adrián Naveda‐Rodríguez

United States Department of Agriculture Wildlife Services: Staff Publications

Black vultures (Coragyps atratus) provide invaluable ecological services through disposal of carrion and the mobilization of energy within the landscape. Human‐wildlife conflicts with these birds have increased as populations have grown and the species distribution has expanded. We identify critical science needed to understand conflict between black vultures and humans to inform effective management of this species in North America. It is imperative that diagnostic criteria supporting the identification of the impacts of black vulture on livestock be standardized and verified. Management guidelines that take these criteria into account will enable reduction in the potential for black‐vulture‐farmer conflict …