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The Effect Of Different Ram Introducing Procedures (Protocol 66) On Fertility Parameters In Anatolian Merino Ewes During Breeding Season, Şükrü Dursun Jan 2022

The Effect Of Different Ram Introducing Procedures (Protocol 66) On Fertility Parameters In Anatolian Merino Ewes During Breeding Season, Şükrü Dursun

Turkish Journal of Veterinary & Animal Sciences

In this study, different applications of ram introduction at the beginning of the breeding season were investigated in terms of their effects on some fertility parameters. The rams were introduced to the herd (Farm II), removed for 6 days, and reintroduced again in the experiment group, while the rams stayed within the herd (Farm I) all of the breeding season in the control group. In both farms, ewes were hand mated. These practices were performed in two consecutive breeding seasons of 2014 and 2015. In farm II, in the following 13 days of the reintroduction of rams, 83.4% and 83.7% …


Effects Of Pueraria Lobata Leaf Powder As A Feed Additive On The Immune System And Growth Performance Of Broiler Chickens, Jianping Gong, Dong Wu, Mengchu Li, Xiaoyu Qiu, Ying Jiang, Jie Zhang, Wenping Huang Jan 2022

Effects Of Pueraria Lobata Leaf Powder As A Feed Additive On The Immune System And Growth Performance Of Broiler Chickens, Jianping Gong, Dong Wu, Mengchu Li, Xiaoyu Qiu, Ying Jiang, Jie Zhang, Wenping Huang

Turkish Journal of Veterinary & Animal Sciences

The present research assessed the effect of different levels of Pueraria lobate leaf (PLL) on growth performance, immunity, antioxidant capacity, and blood index in broiler feed. A total of 384 at 21 days old chicks were assigned to 1 of 4 dietary treatments to examine the benefits of basal diet, basal diet +1% PLL, basal diet +2% PLL and basal diet +3% PLL. The trial was divided into 2 time periods, including starter from days 21-49 and finisher from days 50-70. The addition of 2% and 3% PLL powder to diets increased total protein content, triglycerides, albumin, and low-density lipoprotein …


Display Site Selection By Male Ruffed Grouse In The Upper Great Lakes Region, Seth Finkel Jan 2022

Display Site Selection By Male Ruffed Grouse In The Upper Great Lakes Region, Seth Finkel

Dissertations, Master's Theses and Master's Reports

The Ruffed Grouse (Bonasa umbellus) is widely known for its characteristic territorial drumming display. In this study, I used ruffed grouse drumming survey data from Minnesota and Michigan, in a series of mixed logistic models, to identify drivers of drumming log selection by reproductive male ruffed grouse. I collected drumming stage data utilizing a paired-random sampling structure. I used information theoretic model selection to examine three sets of a priori mixed logistic models: one for the entirety of my Minnesota dataset, one consisting of stages identified in aspen stands in Minnesota, and one for my Michigan dataset. In …


The Atlantic Surfclam Fishery And Offshore Wind Energy Development: 2. Assessing Economic Impacts, Andrew M. Scheld, Jennifer Beckensteiner, Daphne M. Munroe, Eric N. Powell, Sarah Borsetti, Eileen E. Hofmann, John M. Klinck Jan 2022

The Atlantic Surfclam Fishery And Offshore Wind Energy Development: 2. Assessing Economic Impacts, Andrew M. Scheld, Jennifer Beckensteiner, Daphne M. Munroe, Eric N. Powell, Sarah Borsetti, Eileen E. Hofmann, John M. Klinck

CCPO Publications

The Atlantic surfclam (Spisula solidissima) fishery generates approximately USD 30 million in landings revenues annually, distributed across ports throughout the US Mid-Atlantic and Northeast. Overlap between areas of Atlantic surfclam harvests and offshore wind energy leasing make the fishery vulnerable to exclusion and effort displacement as development expands in the region. An existing integrated bioeconomic agent-based model, including spatial dynamics in Atlantic surfclam stock biology, heterogeneous captain behaviour, and federal management processes, was extended to incorporate costs and revenues for fishing vessels and processors and used to evaluate the potential economic effects of offshore wind development on the …


Changes In The Zooplankton Community In Barren River Lake (South Central Ky) Between 2008 And 2020, Laurel Philpott Jan 2022

Changes In The Zooplankton Community In Barren River Lake (South Central Ky) Between 2008 And 2020, Laurel Philpott

Mahurin Honors College Capstone Experience/Thesis Projects

Zooplankton are small aquatic animals that serve an important role in transferring energy from phytoplankton to higher trophic levels. The zooplankton community composition in Barren River Lake from 2008 and 2020 was compared. A field study was conducted to not only describe the seasonal population dynamics of zooplankton in Barren River Lake, but also to determine if an invasive zooplankton, Daphnia lumholtzi, was present. While D. lumholtzi was found throughout Barren River Lake in 2008, it was absent from both resampled sites in 2019 and 2020. This, along with erratic patterns of emergence in several other zooplankton species, indicates …


Effects Of Melatonin Implantation On The Activity Levels Of Captive Snow Buntings (Plectrophenax Nivalis), Zoë Ward Jan 2022

Effects Of Melatonin Implantation On The Activity Levels Of Captive Snow Buntings (Plectrophenax Nivalis), Zoë Ward

Mahurin Honors College Capstone Experience/Thesis Projects

In vertebrates, melatonin regulates many components of the circadian rhythm; depending on the organism’s location and time of year, the pineal gland will produce melatonin accordingly, controlling the sleep-wake cycle and breeding physiologies. However, locations at the poles in which the sun is above the horizon for multiple days at a time pose unique challenges for the organisms living there. The goal of this study was to examine how the implantation of melatonin in an arctic-breeding songbird affects its activity levels and circadian rhythm. The subject of this study, the snow bunting (Plectrophenax nivalis), is a small songbird …


Growing South Dakota (Fall 2021 / Winter 2022), College Of Agriculture, Food And Environmental Sciences Jan 2022

Growing South Dakota (Fall 2021 / Winter 2022), College Of Agriculture, Food And Environmental Sciences

Growing South Dakota (Publication of the College of Agriculture, Food and Environmental Sciences)

[Page] 3 SDSU Launches New Professional Program in Veterinary Medicine
[Page] 7 The 6th Generation
[Page] 9 First-Gen Proud
[Page] 11 Student Success
[Page] 21 Alumni News
[Page] 27 CAFES News and Updates
[Page] 45 Jackrabbits Now and Then: A Current Student and Alumni Q&A


Comparisons Of Biochemical Compositions In Marsh Frog (Pelophylax Ridibundus)(Anura; Ranidae) Grown In Different Conditions; Wild, Semicultured And Cultured Ones, Emrah Şi̇mşek, Ahmet Alkaya, Hülya Şerefli̇şan, Ayşe Özyilmaz Jan 2022

Comparisons Of Biochemical Compositions In Marsh Frog (Pelophylax Ridibundus)(Anura; Ranidae) Grown In Different Conditions; Wild, Semicultured And Cultured Ones, Emrah Şi̇mşek, Ahmet Alkaya, Hülya Şerefli̇şan, Ayşe Özyilmaz

Turkish Journal of Zoology

Frogs can be added to a list of different raw materials which have sustainable economic value to their producers. Therefore, the biochemical attributes of the frogs require further scientific scrutiny. The major objective of the current study is to investigate some biochemical compositions of edible portions of Pelophylax ridibundus (Pallas, 1771) grown in different conditions. The wild frogs, semicultured frogs, and cultured frogs were investigated regarding female and male specimens, leading to six groups that were determined to investigate the biochemical features of frogs. The results show that they (all frogs in all six groups) have low lipid contents (p < 0.05). The protein contents of the frogs varied in the range of 10.54%-16.10%. The lowest ash contents were found in semicultured male and female frogs. The average moisture contents were roughly 80% for all specimens. The major fatty acids were C16:0, C18:0, C18:1n9, C18:2n6, and C20:4n6 for wild, semicultured, and cultured frogs, respectively, for both sexes, showing their respective amounts varied among groups. All in all, the results show that there exist some differences in the nutritional content of frogs grown in different


Time To Stop Pretending We Don’T Know Other Animals Are Sentient Beings, Marc Bekoff Jan 2022

Time To Stop Pretending We Don’T Know Other Animals Are Sentient Beings, Marc Bekoff

Animal Sentience

Rowan et al.’s target article is an outstanding review of some of the history of the science of sentience, but one would have liked to see a much stronger “call to action.” We don’t need any more data to know that many other animals are sentient beings whose lives must be protected from harm in a wide variety of contexts. It is not anti-science to want more action on behalf of other animals right now.


Effect Of Biochar As A Feedlot Pen Surface Amendment On Manure Nutrient Capture, J. L. Sperber, Braden C. Troyer, Mitchell M. Norman, Levi J. Mcphillips, Heather Nobert, Andrea K. Watson, Galen E. Erickson Jan 2022

Effect Of Biochar As A Feedlot Pen Surface Amendment On Manure Nutrient Capture, J. L. Sperber, Braden C. Troyer, Mitchell M. Norman, Levi J. Mcphillips, Heather Nobert, Andrea K. Watson, Galen E. Erickson

Nebraska Beef Cattle Reports

Two mass balance experiments were conducted during winter and summer seasons to evaluate the effect of spreading biochar on the feedlot pen surface on manure nutrient retention. The winter experiment (Dec to June) evaluated three treatments including biochar spread to pen surface (approximately 54 lb of biochar per steer), hydrated lime spread to pen surface (cooperation with UNL Environmental Engineering; approximately 68 lb per steer) and negative control (no treatment applied). The summer experiment (June to Nov) evaluated biochar treatment (approximately 68 lb of biochar per steer) against negative control. Biochar utilized in winter and summer was unprocessed and sourced …


Significance Of Autumn And Winter Food Consumption For Reproduction By Southern Beaufort Sea Polar Bears, Ursus Maritimus, Blaine D. Griffen, John P. Whiteman, Sariah Pullan Jan 2022

Significance Of Autumn And Winter Food Consumption For Reproduction By Southern Beaufort Sea Polar Bears, Ursus Maritimus, Blaine D. Griffen, John P. Whiteman, Sariah Pullan

Biological Sciences Faculty Publications

Polar bears (Ursus maritimus) in the southern Beaufort Sea experience long annual periods when preferred seal prey are scarce or are unavailable. Consumption of bowhead whale (Balaena mysticetus) carcasses from native Alaskan subsistence hunting is increasingly common for onshore polar bears, yet the energetic consequences of this consumption remain unclear. We use data on bears captured repeatedly over periods that encompassed autumn and winter, combined with calculations, to show that adult female bears likely consume an average of at least 4 seal equivalents during both autumn and winter periods and that considerable variation in energy intake …


A Characterization Of The Sandy Beach Surf Zone Fish Community And Their Ecology In Northern California And The Effects Of Marine Protected Areas, Katie B. Terhaar Jan 2022

A Characterization Of The Sandy Beach Surf Zone Fish Community And Their Ecology In Northern California And The Effects Of Marine Protected Areas, Katie B. Terhaar

Cal Poly Humboldt theses and projects

Historically written off as dull and homogenous, the dynamics of the sandy beach surf zone remains under studied world-wide. Northern California has been no exception to this global standard, as the sandy beach surf zone ecosystem in this region has yet to be characterized, and the effect of Marine Protected Areas (MPAs) on the fish and macroinvertebrate community fully ascertained.

Considered data-poor by local wildlife officials, commercially, recreationally and culturally important Amphistichus rhodoterus (redtail surfperch) and common Hyperprosopon ellipticum (silver surfperch) utilize the sandy beach surf zone in Northern California. Little is known about the effect of various environmental factors, …


Activity Patterns Of The Del Norte Salamander (Plethodon Elongatus): Monitoring Plethodontid Behavior Using Pit Tag Surveys, Sabrina Horrack Jan 2022

Activity Patterns Of The Del Norte Salamander (Plethodon Elongatus): Monitoring Plethodontid Behavior Using Pit Tag Surveys, Sabrina Horrack

Cal Poly Humboldt theses and projects

Semi-fossorial plethodontid salamanders exhibit behavioral plasticity to avoid desiccation, retreating underground to shelter from adverse conditions such as low precipitation and high temperatures. In this study, I used passive integrated transponder (PIT) tag surveys to monitor this behavior in the Del Norte salamander (Plethodon elongatus), a small plethodontid native to northwestern California and southwestern Oregon. Within its range, a climatic gradient exists in which coastal areas experience milder temperatures and high precipitation, while inland areas tend to have colder winters, hotter summers, and lower precipitation. By monitoring the activity patterns of this species in inland and coastal areas, …


Evaluating Muskellunge (Esox Masquinongy) Catch-And-Release Mortality At Elevated Summer Water Temperature, Ian Taylor Booth Jan 2022

Evaluating Muskellunge (Esox Masquinongy) Catch-And-Release Mortality At Elevated Summer Water Temperature, Ian Taylor Booth

Graduate Theses, Dissertations, and Problem Reports (ETD)

Angling for Muskellunge (Esox masquinongy) has become widespread and increasingly popular throughout the fish’s range. Current management strategies for Muskellunge include high minimum harvest lengths (>1016mm), closed seasons, and catch-and-release regulations. Due to these strategies and angler sentiments, up to 97% of Muskellunge caught today are released by anglers assuming they will live and be caught again in the future. Previous research on catchand-release mortality in Muskellunge has suggested relatively low mortality rates (0%-5%). However, these studies were all conducted within the fish’s thermal optimum and generally at water temperatures25°C during the summer months, representing a need to evaluate …


Population Characteristics Of Three Black Bass Species In The Upper Ohio River Drainage, Levi Foster Brown Jan 2022

Population Characteristics Of Three Black Bass Species In The Upper Ohio River Drainage, Levi Foster Brown

Graduate Theses, Dissertations, and Problem Reports (ETD)

In West Virginia, species of black bass are economically and ecologically important and support popular fisheries. In the state’s large, navigable river systems, recent information suggests that anglers consider these fisheries diminished relative to their historic stocks. This study sought to describe the population characteristics of Largemouth, Smallmouth, and Spotted Bass in the upper Ohio River drainage and evaluate possible management actions. Low relative abundances coupled with poor growth estimates for Largemouth and Spotted Bass suggests that a suite of environmental and anthropogenic factors may be reducing the quality of their recreational fisheries. Conversely, demographic estimates produced for Smallmouth Bass …


Genetic Analysis And Telemetry Study Of Migration Habits Of The Endangered Atlantic Sturgeon, Cassia Marie Busch Jan 2022

Genetic Analysis And Telemetry Study Of Migration Habits Of The Endangered Atlantic Sturgeon, Cassia Marie Busch

Graduate Theses, Dissertations, and Problem Reports (ETD)

Atlantic sturgeon are a long-lived anadromous fish that ranged from Labrador, Canada to Florida, US. Due to overharvest in the late 1800’s and 1900’s, Atlantic sturgeon populations across the coast experienced a dramatic population crash. Recovery of this species has faced challenges due to anthropogenic threats, such as vessel strikes, bycatch, and habitat degradation. In 2012, Atlantic sturgeon were added to the United States Endangered Species Act (ESA). Under the ESA, populations were listed as five distinct population segments (DPS), reflecting their geographic arrangement and genetic structure: Gulf of Maine DPS (threatened), New York Bight DPS (endangered), Chesapeake DPS (endangered), …


Impact Of Haemonchus Contortus On Feed Efficiency And Feeding Behavior Of Katahdin And Suffolk Lambs, Camren L. Maierle Jan 2022

Impact Of Haemonchus Contortus On Feed Efficiency And Feeding Behavior Of Katahdin And Suffolk Lambs, Camren L. Maierle

Graduate Theses, Dissertations, and Problem Reports (ETD)

Nutritional impact of internal parasitism, specifically Haemonchus contortus (Hc), is a significant contributor to production losses in small ruminants. Both chronic and subclinical infections generate millions of dollars of losses worldwide. Understanding the nutritional impact of Hc on lamb performance is crucial in determining the additional nutrient requirements of infected individuals. The aim of this study was to evaluate nutritional impact of Hc on infected Katahdin lambs with extensive genetic selection for parasite resistance and susceptible Suffolk lambs. Growth, feeding behavior, and feed efficiency (RFI. F:G) were evaluated during artificial Hc infection. Katahdin ewes from the Virginia …


Smallmouth Bass (Micropterus Dolomieu) Population Characteristics And An Evaluation Of Management Responses In Two West Virginia Watersheds, Jacob D. Harrell Jan 2022

Smallmouth Bass (Micropterus Dolomieu) Population Characteristics And An Evaluation Of Management Responses In Two West Virginia Watersheds, Jacob D. Harrell

Graduate Theses, Dissertations, and Problem Reports (ETD)

Smallmouth Bass (Micropterus dolomieu) population characteristics were examined within the Tygart and Cheat River watersheds of north-central West Virginia. Growth, mortality and recruitment were examined for each individual population prior to modeling potential effects of various management schemes. Smallmouth Bass were sampled for total length and weight, aged using sagittal otoliths and sexed through observations of gonadal or ovarian development. Growth for each population was examined using von Bertalanffy growth models and assessed for variation among populations. Population demographic characteristics differed between and among populations, most noticeably between riverine and lacustrine habitat, whereby growth, mortality and recruitment were higher …


Revisiting Donald Griffin, Founder Of Cognitive Ethology, Carolyn A. Ristau Jan 2022

Revisiting Donald Griffin, Founder Of Cognitive Ethology, Carolyn A. Ristau

Animal Sentience

Donald Griffin’s writings, beginning with The Question of Animal Awareness (1976), strove to persuade scientists to study the possibility of animal sentience, the basis of Rowan et al.’s efforts to promote animal well-being. Facing great hostility (but also some acceptance) for his ideas, Griffin initially avoided animal welfare advocacy, fearing it would further undermine his efforts to gain recognition of animal sentience. In later years, however, he began to ponder the ethical implications of animal sentience, intending to study wild elephants’ communication and social behavior to better understand their experienced life and apply it to improving conservation methods. As he …


The Reality And Prevalence Of Animal Sentience, Antonio Damasio Jan 2022

The Reality And Prevalence Of Animal Sentience, Antonio Damasio

Animal Sentience

Rowan et al use findings from neurobiology, clinical neurology, and general biology to argue for the extensive presence of sentience in animals, but they are wisely cautious concerning when in the phylogenetic scale that emergence occurred.


A Comparison Of Chimpanzee Wound Rates Before And During Covid-19 Zoo Closures, Robin Elana Salak Jan 2022

A Comparison Of Chimpanzee Wound Rates Before And During Covid-19 Zoo Closures, Robin Elana Salak

All Master's Theses

Visitor effect studies have had inconsistent impacts on animals, due in part to the inability to control for all confounding variables such as time of day, seasonal weather patterns, and so forth. This study represents the first instance where chimpanzee (Pan troglodytes) wounding frequencies were investigated across extensive time periods in the presence and complete absence of visitors, thus eliminating many visitor-related variables. Additional variables were eliminated through the zoo selection process, based on institutional responses to a 29-question survey, providing a novel approach to the question of visitor effects. The aim of this study was to determine …


Factors Influencing Intestinal Parasite In Black-And-White Ruffed Lemurs (Varecia Variegata), Eliette Noromalala Jan 2022

Factors Influencing Intestinal Parasite In Black-And-White Ruffed Lemurs (Varecia Variegata), Eliette Noromalala

All Master's Theses

Ecological factors, such as feeding behavior and climatic seasonality, might influence intestinal parasite infection and patterns in non-human primates. Here, we examined if frugivory levels and climate (i.e., temperature and rainfall) were associated with parasite patterns in black-and-white ruffed lemurs (Varecia variegata). Feeding data using 5-min focal sampling, climate data, and fecal samples from V. variegata (n = 23) at the “Mangevo” site were collected from February through May 2019. Microscopic examinations of fecal flotation and sedimentation were done to identify and count parasites. Nematoda (Callistoura vauceli, and Strongyloides sp.) Ciliophora (Balantidium sp.), Coccidia ( …


Characterizing And Predicting Beaver Pond Habitat In Kittitas County, Washington, Kylie Vroman Jan 2022

Characterizing And Predicting Beaver Pond Habitat In Kittitas County, Washington, Kylie Vroman

All Master's Theses

North American Beavers (Castor canadensis) are important ecosystem engineers in the Pacific Northwest (PNW), as they provide ecosystem services and create habitats that benefit aquatic species, watersheds, and riparian vegetation. Even though the species has been coined a “nuisance” in some settings, it is common for environmental agencies to capture beavers and relocate them to areas where it is less likely for them to cause damage. This study geospatially modeled the Kittitas County landscape to identify areas of suitable habitat. Nine existing beaver ponds in Kittitas County were investigated; three of which were prior relocation sites that had failed, three …


Epigenetic Buffering In Introduced House Sparrows, M. Ellesse Lauer Jan 2022

Epigenetic Buffering In Introduced House Sparrows, M. Ellesse Lauer

College of Graduate Studies: Theses & Dissertations

Epigenetic buffering, as an environmentally induced increase in variance of epigenetic states that increases phenotypic variation to buffer populations against decreased fitness, may be a factor that resolves the genetic paradox of introduced species. DNA methylation is a molecular mechanism that could facilitate epigenetic buffering by changing in response to environmental stress. Therefore, epigenetic buffering can be detected through increased variance in DNA methylation in novel or heterogeneous environments. Introduced house sparrows (Passer domesticus) have well-documented phenotypic changes with low genetic diversity, high epigenetic diversity, and high variance in DNA methylation that provide a characteristic signature of epigenetic buffering. …


Sentience In Decapod Crustaceans: A General Framework And Review Of The Evidence, Andrew Crump, Heather Browning, Alex Schnell, Charlotte Burn, Jonathan Birch Jan 2022

Sentience In Decapod Crustaceans: A General Framework And Review Of The Evidence, Andrew Crump, Heather Browning, Alex Schnell, Charlotte Burn, Jonathan Birch

Animal Sentience

We outline a framework for evaluating scientific evidence of sentience, focusing on pain experience. It includes eight neural and cognitive-behavioural criteria, with confidence levels for each criterion reflecting the reliability and quality of the evidence. We outline the rationale for each criterion and apply our framework to a controversial sentience candidate: decapod crustaceans. We have either high or very high confidence that true crabs (infraorder Brachyura) satisfy five criteria, amounting to strong evidence of sentience. Moreover, we have high confidence that both anomuran crabs (infraorder Anomura) and astacid lobsters/crayfish (infraorder Astacidea) meet three criteria—substantial evidence of sentience. The case is, …


Zebra Mussel Length-Weight Relationships Across Various Substrate Types In Lake Bemidji, Mitch Kehne Jan 2022

Zebra Mussel Length-Weight Relationships Across Various Substrate Types In Lake Bemidji, Mitch Kehne

Journal of Earth and Life Science

As of November 2021, zebra mussels were confirmed in 270 Minnesotan lakes with another 232 lakes listed as infested due to their connection or proximity to where zebra mussels have been found. With lack of effective treatments to impede their spread, zebra mussels continue to colonize new areas causing ecological as well as economic harm. The goal of this study was to establish a length-weight relationship for the zebra mussel population in Lake Bemidji using shell length (SL) and wet weight (WW), as well as to assess substrate type and log transformed shell length as predictors of log transformed zebra …


Changes In The Minnesota Northern Pike Population Over The Past Thirty Years, Joey Severin Jan 2022

Changes In The Minnesota Northern Pike Population Over The Past Thirty Years, Joey Severin

Journal of Earth and Life Science

Northern pike Esox lucius are one of the most popular game fish in Minnesota. Many anglers have noticed that northern pike seemed to decrease in size throughout much of this state. Catch per unit of effort (CPUE) drives average weight for northern pike; within lakes, as CPUE goes up average weight decreases. Decreases in size has led the Minnesota Department of Natural Resources (MNDNR) to implement new regulations on northern pike. The MNDNR noticed that not all the state has this same problem with Northern Pike, and has broken down the state into three zones, with different protected slots and …


Oregon State Rank Assessment For Cope's Giant Salamander (Dicamptodon Copei), Eleanor P. Gaines Jan 2022

Oregon State Rank Assessment For Cope's Giant Salamander (Dicamptodon Copei), Eleanor P. Gaines

Institute for Natural Resources Publications

Oregon state conservation status assessment for Cope's giant salamander (Dicamptodon copei) using NatureServe methodology, 2022.


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 Jan 2022

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 Jan 2022

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 …