Veterinary Medicine Commons^™

Interaction Of Sweet Bran Inclusion And Corn Processing Method In Beef Finishing Diets, Rebecca L. Sjostrand, Levi J. Mcphillips, Braden C. Troyer, Maggie Youngers, Rick Stock, J. C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

The effects of corn processing method and Sweet Bran concentration on finishing cattle performance and carcass characteristics were evaluated in steam-flaked corn or a blend of high-moisture and dry-rolled corn-based diets. Sweet Bran was included at 0, 20, or 40% of diet dry matter. When cattle were fed 0% Sweet Bran, feeding steam-flaked corn resulted in a 11.7% improvement in feed conversion and heavier hot-carcass weight compared to feeding high-moisture/ dry-rolled corn. As Sweet Bran increased in the diet, there was a linear improvement in feed conversion for high-moisture/dry-rolled corn-fed steers and no change in feed conversion for steam-flaked corn-fed …

Effect Of Rapeseed Inclusion In Late-Summer Planted Oat Pasture On Growing Performance Of Beef Steers, Devin A. Jakub, Hannah E. Riley, Kristin E. Hales, Steven D. Shackelford, Harvey C. Freetly, M. E. Drewnoski

Nebraska Beef Cattle Reports

An oat monoculture was planted in late summer at 100 lb/ac and compared to oats planted at 50 lb/ac with rapeseed included at 3 lb/ac. Seed cost of the oat monoculture ($20/ac) was greater than the mix ($15/ac). Initial forage yield was not affected by the inclusion of rapeseed with fall oat. Calf gain was significantly greater and cost of gain was significantly decreased when rapeseed was included due to the combination of greater gains and lesser seed cost. Including rapeseed in late summer planted oats may be beneficial for producers who want to graze growing calves in the fall.

Interaction Of Urea With Frequency And Amount Of Distillers Grains Supplementation On Growing Steer Rumen Digestion Parameters, Haley F. Linder, Joshua E. Sebade, Tyler J. Spore, M. E. Drewnoski, J. C. Macdonald

Nebraska Beef Cattle Reports

Ruminally cannulated steers were used in 8 × 6 row-column design with 8 animals and 6 periods. Treatment design was a 2 × 2 × 2 factorial, with factors including amount of supplementation, frequency of supplementation, and inclusion of urea. Hay dry matter intake was reduced by increased amount of supplementation and by decreased frequency of supplementation. Total VFA concentration did not differ among treatments. Rumen ammonia-N concentration was impacted by an interaction of amount of supplementation and inclusion of urea but there was no effect of supplementation frequency. In situ NDF disappearance did not differ between daily and alternate …

Comparison Of Partially Confined And Traditional Cow-Calf Systems, Zac E. Carlson, Levi J. Mcphillips, Galen E. Erickson, M. E. Drewnoski, J. C. Macdonald

Nebraska Beef Cattle Reports

Production of cow-calf pairs and grow/finish performance of calves from a partially-confined, fall-calving, intensive cow-calf system were compared to a traditional, spring-calving, extensive cow-calf system. Body condition was lower at breeding and weaning for the fall-calving alternative system compared to the traditional, spring-calving system. Conception, calving, and weaning rates were not different among treatments. Weaning weights were lower for the fall-calving alternative system than traditional, spring-calving system. Following weaning, calves were grown for 117 d and then subsequently finished to the same target fatness for both systems. In the grower phase, gain was greater and feed conversion improved for the …

Genetic And Genomic Architecture In Eight Strains Of The Laboratory Opossum Monodelphis Domestica, Xiao Xiong, Paul B. Samollow, Wenqi Cao, Richard Metz, Chao Zhang, Ana C. Leandro, John L. Vandeberg, Xu Wang

School of Medicine Publications

The gray short-tailed opossum (Monodelphis domestica) is an established laboratory-bred marsupial model for biomedical research. It is a critical species for comparative genomics research, providing the pivotal phylogenetic outgroup for studies of derived vs ancestral states of genomic/epigenomic characteristics for eutherian mammal lineages. To characterize the current genetic profile of this laboratory marsupial, we examined 79 individuals from eight established laboratory strains. Double digest restriction site-associated DNA sequencing and whole-genome resequencing experiments were performed to investigate the genetic architecture in these strains. A total of 66,640 highquality single nucleotide polymorphisms (SNPs) were identified. We analyzed SNP density, average heterozygosity, nucleotide …

Effects Of Supplemented Intra- And Extra-Cellular Trehalose On Cryopreservation Of Feline Oocytes, Saengtawan Arayatham

Chulalongkorn University Theses and Dissertations (Chula ETD)

Study 1 aimed at examining the effects of different stages of oocyte maturation and trehalose concentrations on freezing ability and developmental capability of feline oocytes. The immature and matured feline oocytes were cryopreserved and thawed. They were assessed for developmental competence. The effects of different concentrations of trehalose (0, 0.125, 0.25, 0.5, 1 M) on the freezing ability of feline oocytes were tested. The cryopreservation generally induced poor embryo development, while immature oocytes were more susceptible to cryodamage compared with the matured oocytes (P<0.05). Incubation of oocytes with high concentrations of trehalose (0.5, 1 M) significantly reduced the developmental competence. Optimal concentrations of trehalose during cryopreservation of immature and matured oocytes were different (0.125 M and 0.25 M, respectively). It is concluded that stages of meiotic maturation affected the freezing ability of feline oocytes. Optimal concentration of trehalose was differently required for immature and matured feline oocytes. Study 2 aimed at examining the effect of membrane-permeable trehalose on the freezing ability of feline oocytes matured in vitro. intracellular trehalose (trehalose hexaacetate; Tre-(OAc)6) was synthesized from trehalose precursor and subjected to spectroscopic characterization. The membrane permeability of the Tre-(OAc)6 was investigated by incubating oocytes with different concentrations of Tre-(OAc)6 (3, 15, and 30 mM) and optimum concentration and the toxicity of Tre-(OAc)6 were subsequently assessed. The effects of Tre-(OAc)6 on freezing ability in terms of apoptotic gene expression and developmental competence of in-vitro matured oocytes were examined, respectively. The Tre-(OAc)6 permeated into the ooplasm of cat oocytes in a dose- and time-dependent manner. The highest concentration of intracellular trehalose was detected when the oocytes were incubated for 24 h with 30 mM Tre-(OAc)6. For the toxicity test, incubation of oocytes with 3 mM Tre-(OAc)6 for 24 h did not affect maturation rate and embryo development. However, high doses of Tre-(OAc)6 (15 and 30 mM) significantly reduced maturation and fertilization rates (P < 0.05). In addition, frozen-thawed oocytes treated with 3 mM Tre-(OAc)6 significantly upregulated anti-apoptotic (BCL-2) gene expression compared with the control (0 mM) and other Tre-(OAc)6 concentrations (15 and 30 mM). Oocyte maturation in the presence of 3 mM Tre-(OAc)6 prior to cryopreservation significantly improved oocyte developmental competence in terms of cleavage and blastocyst rates when compared with the control group (P < 0.05). Our results lead us to infer that increasing the levels of intracellular trehalose by Tre-(OAc)6 during oocyte maturation improves the freezing ability of feline oocytes, albeit at specific concentrations. Study 3 aimed at examining the effects of combination of intra-cellular (Tre-(OAc)6) and extra-cellular (α,α-trehalose) trehalose on freezing ability of feline oocytes. Optimal concentrations of Tre-(OAc)6 (0, 1.5, and 3 mM) and trehalose (0, 0.125, 0.25, and 0.5 M) were investigated for cryopreservation of matured feline oocytes. The combination of the two optimal concentrations were subsequently examined. The results showed that 3 mM of Tre-(OAc)6 improved post-thawed developmental competence, while extra-cellular trehalose at 0.25 M significant enhanced freezing ability of feline oocytes (P<0.05). The combination of intra- and extra-cellular trehalose significantly improved developmental capability of frozen-thawed matured feline oocytes compared to non-trehalose control.

Metaproteomic Analysis Of Gut Resistome In The Cecal Microbiota Of Fattening Pigs Raised Without Antibiotics, Pamornya Buthasane

Chulalongkorn University Theses and Dissertations (Chula ETD)

Improper use of antibiotics in swine could reduce commensal bacteria and possibly increase pathogen infections via the gut resistome. This study aimed to compare the metaproteomic profiles of gut resistome and related metabolism in the cecal microbiota of fattening pigs raised under antibiotic-free (ABF) conditions with those of ordinary industrial pigs (controls, CTRL). The top three relative abundant microbials in both groups were Escherichia coli, Ruminococcus and Lactobacillus, followed by Bacteroides and Bifidobacterium. E. coli, Lactobacillus and Bacteroides were found to be increased in the CTRL group, whereas Ruminococcus and Clostridium were greater in the ABF group. The highest abundance …

Experimental Elucidation Of The Life Cycle Of Drepanocephalus Spathans (Digenea: Echinostomatidae) With Notes On The Morphological Plasticity Of D. Spathans In The United States, Neely R. Alberson, Thomas G. Rosser, Tommy King, Ethan T. Woodyard, Lester Khoo, Wes A. Baumgartner, Daviod J. Wise, Linda M. Pote, Fred L. Cunningham, Matt J. Griffin

United States Department of Agriculture Wildlife Services: Staff Publications

The echinostomatid Drepanocephalus spathans (syn. Drepanocephalus auritus) parasitizes the doublecrested cormorant Phalacrocorax auritus. In North America, the marsh rams-horn snail Planorbella trivolvis and ghost rams-horn snail Biomphalaria havanensis serve as snail intermediate hosts, both of which inhabit catfish aquaculture ponds in the southeastern United States. Studies have demonstrated D. spathans exposure can be lethal to juvenile channel catfish Ictalurus punctatus. Two studies were undertaken to elucidate the life cycle of D. spathans to establish a developmental time line. In both studies, D. spathans cercariae collected from naturally infected P. trivolvis individuals were used to infect channel catfish …

Scavenging Vs Hunting Affects Behavioral Traits Of An Opportunistic Carnivore, Mitchell A. Parsons, Andrew Garcia, Julie K. Young

United States Department of Agriculture Wildlife Services: Staff Publications

Background. Human-induced changes to ecosystems transform the availability of resources to predators, including altering prey populations and increasing access to anthropogenic foods. Opportunistic predators are likely to respond to altered food resources by changing the proportion of food they hunt versus scavenge. These shifts in foraging behavior will affect species interactions through multiple pathways, including by changing other aspects of predator behavior such as boldness, innovation, and social structure. Methods. To understand how foraging behavior impacts predator behavior, we conducted a controlled experiment to simulate hunting by introducing a prey model to captive coyotes (Canis latrans) and compared their behavior …

Influence Of Landscape Attributes On Virginia Opossum Density, David A. Bernasconi, Wesley C. Dixon, Matthew T. Hamilton, James L. Helton, Richard B. Chipman, Amy T. Gilbert, James C. Beasley, Olin E. Rhodes Jr., Guha Dharmarajan

United States Department of Agriculture Wildlife Services: Staff Publications

TheVirginia opossum (Didelphis virginiana), North America's only marsupial, has a range extending from southern Ontario, Canada, to the Yucatan Peninsula, Mexico, and from the Atlantic seaboard to the Pacific. Despite the Virginia opossum's taxonomic uniqueness in relation to other mammals in North America and rapidly expanding distribution, its ecology remains relatively understudied. Our poor understanding of the ecology of this important mesopredator is especially pronounced in the rural southeastern United States. Our goal was to estimate effects of habitat on opossum density within an extensive multiyear spatial capture‐recapture study. Additionally, we compared the results of this spatial capture‐recapture …

Multidisciplinary Engagement For Fencing Research Informs Efficacy And Rancher-To-Researcher Knowledge Exchange, Matthew Hyde, Stewart W. Breck, Alex Few, Jared Beaver, Joshua Schrecengost, Jim Stone, Cameron Krebs, Russell Talmo, Kari Eneas, Rae Nickerson, Kyran E. Kunkel, Julie K. Young

United States Department of Agriculture Wildlife Services: Staff Publications

Across much of the Western United States, recovery of large carnivore populations is creating new challenges for livestock producers. Reducing the risks of sharing the landscape with recovering wildlife populations is critical to private working lands, which play an vital role in securing future energy, water, food, and fiber for an ever-expanding human population. Fencing is an important mitigation practice that many ranchers, land managers, and conservationists implement to reduce carnivore-livestock conflict. While fencing strategies have been reviewed in the literature, research seldom incorporates knowledge from the people who utilize fencing the most (i.e., livestock producers). Incorporating producers and practitioners …

Defining And Assessing Sentience, Barry O. Hughes

Animal Sentience

Precisely what is meant by the term sentience and how does it overlap with being conscious? We accept that animals have feelings but how do we know what they are and can we measure them? It is important that we clarify the terminology underlying these difficult concepts. Over the last 50 years a scientific discipline has developed to tackle these questions in a systematic way. We have to avoid thoughtless anthropomorphism yet we have to try to relate sentience in animals, as appropriate, to corresponding experiences in humans.

The Acute Physiological Response Of Polar Bears To Helicopter Capture, John P. Whiteman, Henry J. Harlow, George M. Durner, Eric V. Regehr, Steven C. Amstrup, Anthony M. Pagano, Merav Ben-David

Biological Sciences Faculty Publications

Many wildlife species are live captured, sampled, and released; for polar bears (Ursus maritimus) capture often requires chemical immobilization via helicopter darting. Polar bears reduce their activity for approximately 4 days after capture, likely reflecting stress recovery. To better understand this stress, we quantified polar bear activity (via collar‐mounted accelerometers) and body temperature (via loggers in the body core [T_abd] and periphery [T_per]) during 2–6 months of natural behavior, and during helicopter recapture and immobilization. Recapture induced bouts of peak activity higher than those that occurred during natural behavior for 2 of 5 bears, …

Longevity Of An Immunocontraceptive Vaccine Effect On Fecundity In Rats, Rebecca Pinkham, Douglas C. Eckery, Richard E. Mauldin, M. Gomm, F. Hill, F. Vial, G. Massei

United States Department of Agriculture Wildlife Services: Staff Publications

Increases in human-wildlife conflicts alongside cultural shifts against lethal control methods are driving the need for alternative wildlife management tools such as fertility control. Contraceptive formulations suitable for oral delivery would permit broader remote application in wildlife species.

This study evaluated the contraceptive effect and immune response to two novel injectable immunocontraceptive formulations targeting the Gonadotropin Releasing Hormone (GnRH): MAF-IMX294 and MAF-IMX294P conjugates, both identified as having potential as oral contraceptives. The study also explored whether in multiparous species immunocontraceptives may either totally prevent reproduction or also affect litter size.

Female rats, chosen as a model species, were given three …

Rapid Changes In Public Perception Toward A Conservation Initiative, Rebecca Niemiec, Richard E.W. Berl, Mireille Gonzalez, Tara L. Teel, Jonathan Salerno, Stewart Breck, Cassiopeia Camara, Matthew Collins, Courtney Scholtz, Dana Hoag, Kevin R. Crooks

United States Department of Agriculture Wildlife Services: Staff Publications

Rapid, widespread changes in public perceptions and behaviors have the potential to influence conservation outcomes. However, few studies have documented whether and how such shifts occur throughout the span of a conservation initiative. We examined the 2020 ballot initiative to reintroduce wolves into Colorado, which passed with less support than prior surveys had estimated. We conducted a postelection survey of Colorado residents using the same methods as our preelection survey to compare responses between surveys and to official election results. Reported voting in favor of wolf reintroduction in the postelection survey decreased in comparison to voting intentions shared in the …

A Model For Leveraging Animal Movement To Understand Spatio-Temporal Disease Dynamics, Mark Q. Wilber, Anni Yang, Raoul Boughton, Kezia R. Manlove, Ryan S. Miller, Kim M. Pepin, George Wittemyer

United States Department of Agriculture Wildlife Services: Staff Publications

The ongoing explosion of fine-resolution movement data in animal systems provides a unique opportunity to empirically quantify spatial, temporal and individual variation in transmission risk and improve our ability to forecast disease outbreaks. However, we lack a generalizable model that can leverage movement data to quantify transmission risk and how it affects pathogen invasion and persistence on heterogeneous landscapes. We developed a flexible model ‘Movement-driven modelling of spatio-temporal infection risk’ (MoveSTIR) that leverages diverse data on animal movement to derive metrics of direct and indirect contact by decomposing transmission into constituent processes of contact formation and duration and pathogen deposition …

Large- And Small-Scale Climate Influences Spring Migration Departure Probability Of American White Pelicans, D. Tommy King, Guiming Wang, Fred L. Cunningham

United States Department of Agriculture Wildlife Services: Staff Publications

Endogenous (e.g., age and sex) and exogenous (e.g., climate and resource availability) factors influence avian migration phenology. However, little is known regarding the migration ecology of birds at the non-breeding grounds, including the American white pelican (Pelecanus erythrorhynchos). We used Global Positioning System transmitters to track the movements and migration of 51 pelicans from 2002 to 2012. We used the Kaplan–Meier model to estimate pelican spring migration probabilities to quantify partial migration with 94 spring migration events and used the Cox proportional hazards model to evaluate the effects of the North Atlantic Oscillation index (NAOI), Southern Oscillation Index (SOI), and …

Adaptive Risk-Based Targeted Surveillance For Foreign Animal Diseases At The Wildlife-Livestock Interface, Ryan S. Miller, Sarah N. Bevins, Gericke Cook, Ross Free, Kim M. Pepin, Thomas Gidlewski, Vienna Brown

United States Department of Agriculture Wildlife Services: Staff Publications

Animal disease surveillance is an important component of the national veterinary infrastructure to protect animal agriculture and facilitates identification of foreign animal disease (FAD) introduction. Once introduced, pathogens shared among domestic and wild animals are especially challenging to manage due to the complex ecology of spillover and spillback. Thus, early identification of FAD in wildlife is critical to minimize outbreak severity and potential impacts on animal agriculture as well as potential impacts on wildlife and biodiversity. As a result, national surveillance and monitoring programs that include wildlife are becoming increasingly common. Designing surveillance systems in wildlife or, more importantly, at …

Evidence For Irruptive Fluctuation In Axis Deer Of Hawai‘I, Steven C. Hess, Jonathan Sprague, Jacob Muise

United States Department of Agriculture Wildlife Services: Staff Publications

Axis deer on the Hawaiian Islands of Maui, Lāna‘i, and Moloka‘i simultaneously experienced one of the most dramatic population crashes on record in 2020-2021, which coincided with extended drought conditions and prompted an emergency declaration for these islands. This phenomenon has been anecdotally documented during previous drought events in 2011-2012, but never formally studied. Newspaper articles document abundant deer becoming a nuisance to agriculture and natural resources, and then experiencing high mortality during droughts. This phenomenon fits Caughley’s (1970) operational definition of eruptive (sic) fluctuation “…as an increase in numbers over at least two generations, followed by a marked decline.” …

Cultivation Of Industrial Hemp On And Near Airports: Implications For Wildlife Use And Risk To Aviation Safety, Bradley F. Blackwell, Page E. Klug, Lee A. Humberg, Zachary T. Brym, Bryan M. Kluever, Jenna Edwards

United States Department of Agriculture Wildlife Services: Staff Publications

Industrial hemp (Cannabis sativa L.; hemp) is an emerging crop in the United States with little known about bird use or the potential for birds to become an agricultural pest. We identified birds associated with hemp fields, using repeated visits to oilseed plots in North Dakota, USA (n = 6) and cannabinoid (CBD) plots in Florida, USA (n = 4) from August to November 2020. We did not control for plot area or density; our observations were descriptive only. We observed 10 species in hemp, 12 species flying over hemp, and 11 species both foraging in and …

Industrial Hemp As A Resource For Birds In Agroecosystems: Human-Wildlife Conflict Or Conservation Opportunity?, Emily A. Kotten, Iona Hennessy, Bryan M. Kluever, Bradley F. Blackwell, Lee A. Humberg, Page E. Klug

United States Department of Agriculture Wildlife Services: Staff Publications

Industrial hemp (Cannabis sativa L.; hemp) is an emerging crop in the United States with little known about bird use or the potential for birds to become an agricultural pest. We identified birds associated with hemp fields, using repeated visits to oilseed plots in North Dakota, USA (n = 6) and cannabinoid (CBD) plots in Florida, USA (n = 4) from August to November 2020. We did not control for plot area or density; our observations were descriptive only. We observed 10 species in hemp, 12 species flying over hemp, and 11 species both foraging in and …

Evaluation Of Ivermectin Antiviral Activity Against Avian Infectious Bronchitis Virus Using A Chicken Embryo Model, Donald L. Reynolds, E. Barry Simpson

School of Veterinary and Biomedical Sciences: Faculty Publications

Ivermectin is widely used in both animals and humans as an FDA-approved parasiticide. Ivermectin has also been reported to have antiviral activity against several viruses including coronaviruses. There are reports that indicate ivermectin may have some role in diminishing the disease caused by SARS-CoV-2, but the evidence is inconclusive. The objective of this study was to determine if ivermectin was efficacious in inhibiting avian infectious bronchitis virus (IBV, a coronavirus) replication in chicken embryos. Briefly, our approach was to use the Massachusetts vaccine strain of IBV in combination with various doses of ivermectin and then inoculate these preparations into chicken …

Structural Variant-Based Pangenome Construction Has Low Sensitivity To Variability Of Haplotype-Resolved Bovine Assemblies, Alexander S. Leonard, Danang Crysnanto, Zih-Hua Fang, Michael P. Heaton, Brian L. Vander Ley, Carolina Herrera, Heinrich Bollwein, Derek M. Bickhart, Benjamin D. Rosen, Hubert Pausch

School of Veterinary and Biomedical Sciences: Faculty Publications

Advantages of pangenomes over linear reference assemblies for genome research have recently been established. However, potential effects of sequence platform and assembly approach, or of combining assemblies created by different approaches, on pangenome construction have not been investigated. Here we generate haplotype-resolved assemblies from the offspring of three bovine trios representing increasing levels of heterozygosity that each demonstrate a substantial improvement in contiguity, completeness, and accuracy over the current Bos taurus reference genome. Diploid coverage as low as 20x for HiFi or 60x for ONT is sufficient to produce two haplotype-resolved assemblies meeting standards set by the Vertebrate Genomes Project. …

Does Swab Type Matter? Comparing Methods For Mannheimia Haemolytica Recovery And Upper Respiratory Microbiome Characterization In Feedlot Cattle, William B. Crosby, Lee Pinnell, John T. Richeson, Cory Wolfe, Jake Castle, John Dustin Loy, Sheryl P. Gow, Keun Seok Seo, Sarah F. Capik, Amelia R. Woolums, Paul S. Morley

School of Veterinary and Biomedical Sciences: Faculty Publications

Background: Bovine respiratory disease (BRD) is caused by interactions among host, environment, and pathogens. One standard method for antemortem pathogen identification in cattle with BRD is deep-guarded nasopharyngeal swabbing, which is challenging, costly, and waste generating. The objective was to compare the ability to recover Mannheimia haemolytica and compare microbial community structure using 29.5 inch (74.9 cm) deep-guarded nasopharyngeal swabs, 16 inch (40.6 cm) unguarded proctology swabs, or 6 inch (15.2 cm) unguarded nasal swabs when characterized using culture, real time-qPCR, and 16S rRNA gene sequencing. Samples for aerobic culture, qPCR, and 16S rRNA gene sequencing were collected from the …

Rna Nanovaccine Protects Against White Spot Syndrome Virus In Shrimp, Yashdeep Phanse, Supraja Puttamreddy, Duan Loy, Julia Vela Ramirez, Kathleen A. Ross, Ignacio Alvarez-Castro, Mark Mogler, Scott Broderick, Krishna Rajan, Balaji Narasimhan, Lyric C. Bartholomay

School of Veterinary and Biomedical Sciences: Faculty Publications

In the last 15 years, crustacean fisheries have experienced billions of dollars in economic losses, primarily due to viral diseases caused by such pathogens as white spot syndrome virus (WSSV) in the Pacific white shrimp Litopenaeus vannamei and Asian tiger shrimp Penaeus monodon. To date, no effective measures are available to prevent or control disease outbreaks in these animals, despite their economic importance. Recently, double-stranded RNA-based vaccines have been shown to provide specific and robust protection against WSSV infection in cultured shrimp. However, the limited stability of double-stranded RNA is the most significant hurdle for the field application of these …

An Examination Of Ethical Attitudes Towards Wild Pig (Sus Scrofa) Toxicants In The United States, Keith Carlisle, Erin E. Harper, Stephanie A. Shwiff

United States Department of Agriculture Wildlife Services: Staff Publications

This research aims to understand ethical attitudes of the U.S. public towards the use of a toxicant to control wild pigs (Sus scrofa), a destructive invasive species whose population growth is proving difficult to control through conventional management methods. Using a nationwide self-administered survey with 2,186 completed and returned questionnaires, we found that among six different lethal control methods, toxicant usage was the only method that a majority of respondents (51%) found to be unethical, with no significant differences between rural and urban respondents or between respondents from counties with wild pigs and counties where the species is absent. The …

Relationship Between Reproductive Hormones And Migration Distance In A Polygynous Songbird, The Red‑Winged Blackbird (Agelaius Phoeniceus), Michelle A. Eshleman, Page E. Klug, Esther Morales‑Vega, Björn Wissel, Timothy J. Grelves

United States Department of Agriculture Wildlife Services: Staff Publications

Many bird species migrate to southern overwintering locations to avoid harsh conditions at their breeding grounds, but at the cost of an energetically demanding migration that may delay their spring reproductive development. Previous work on the relationship between migration distance and reproductive readiness has primarily focused on early season baseline testosterone in both males and females. However, for females, testosterone alone may not be the appropriate measurement of reproductive development. Estradiol, a metabolite of testosterone that is essential for breeding behaviors and reproduction, should also be measured. Furthermore, baseline testosterone varies throughout the day and may change due to social …

A Systematic Map Of Human-Carnivore Coexistence, Cassandre C. Venumière-Lefebvre, Stewart W. Breck, Kevin R. Crooks

United States Department of Agriculture Wildlife Services: Staff Publications

Carnivore populations globally have largely declined, and coexistence, where humans and carnivores share landscapes, plays a crucial role in carnivore conservation. However, the term “coexistence” is often used in scientific and popular literature without being clearly defined. Herein, we provide a global perspective on what coexistence is and how it is studied. We conducted a systematic map of 366 articles published between 1987 and 2020 to characterize human-carnivore coexistence literature according to coexistence definitions, temporal trends, geographic and taxonomic focus, and four thematic aspects of coexistence: carnivore ecology, human endeavors, social conflict and human-carnivore conflict. We used chi-squared tests and …

Frugivory And Seed Dispersal By Carnivorans, John P. Draper, Julie K. Young, Eugene W. Schupp, Noelle G. Beckman, Trisha B. Atwood

United States Department of Agriculture Wildlife Services: Staff Publications

Seed dispersal is critical to the ecological performance of sexually reproducing plant species and the communities that they form. The Mammalian order Carnivora provide valuable and effective seed dispersal services but tend to be overlooked in much of the seed dispersal literature. Here we review the literature on the role of Carnivorans in seed dispersal, with a literature search in the Scopus reference database. Overall, we found that Carnivorans are prolific seed dispersers. Carnivorans’ diverse and plastic diets allow them to consume large volumes of over a hundred families of fruit and disperse large quantities of seeds across landscapes. Gut …

Aboveground Carbon Responses To Experimental And Natural Hurricane Impacts In A Subtropical Wet Forest In Puerto Rico, Hervé Chevalier, Nicholas V.L. Brokaw, Sheila E. Ward, Jess K. Zimmerman, Aaron B. Shiels, John Bithorn, Samuel Matta Carmona

United States Department of Agriculture Wildlife Services: Staff Publications

Climate change and disturbance make it difficult to project long-term patterns of carbon sequestration in tropical forests, but large ecosystem experiments in these forests can inform predictions. The Canopy Trimming Experiment (CTE) manipulates two key components of hurricane disturbance, canopy openness and detritus deposition, in a tropical forest in Puerto Rico. We documented how the CTE and a real hurricane affected tree recruitment, biomass, and aboveground carbon storage over 15 years. In the CTE treatments, we trimmed branches, but we did not fell trees. We expected that during the 14-year period after initial canopy trimming, regrowth of branches and stems …