Animal Sciences Commons^™

Modeling Wild Rice Bed Health: A Dual Metric Approach For Bed Strength And Invasive Impact, Seth Sisneros-Martinez

Journal of Earth and Life Science

Wild rice (mannoomin; Zizania palustris) is an aquatic grain that grows in slow-moving rivers and shallow bays throughout northern Minnesota. In Headquarters Bay on Leech Lake, wild rice has served as a cultural staple for Indigenous communities for centuries. However, its population has declined in recent years due to multiple environmental issues. One potential contributor is Eurasian watermilfoil (Myriophyllum spicatum; EWM), an invasive species that forms dense mats capable of outcompeting native aquatic vegetation, including wild rice. EWM was first recorded on the southern shoreline of Leech Lake in 2005 and has since become widespread. This study …

The Effect Of Zebra Mussels On Minnesota Fish Communities, Benjamin D. Strei

Journal of Earth and Life Science

Zebra mussels Dreissena polymorpha are an aquatic invasive species that has been spreading quickly throughout Minnesota water bodies since 1989. Zebra mussels are known to change certain morphological conditions in lakes such as turbidity, phytoplankton abundance, and aquatic invertebrate populations. However, studies showing impacts of the infestation of zebra mussels on the health of a fish community have been hard to prove due to a lack of repeated surveys and a suite of other confounding variables such as natural and seasonal variability, plant community, and lake morphometry. Therefore, the objective of this study is to determine whether zebra mussels have …

Artificial Insemination Of Beef Heifers With Multi-Sire Semen, Dempster Christenson, Jordan M. Thomas, Daniel J. Kelly, Richard N. Funston

Nebraska Beef Cattle Reports

This study compared pregnancy rates of beef heifers artificially inseminated with multi-sire semen to single-sire semen. It was hypothesized pregnancy rates resulting from multi-sire semen would be increased compared to single-sire semen. Heifers were artificially inseminated with semen from one of three single-sires or semen from a combination of the same three sires. Pregnancy rates did not significantly differ. Paternity testing suggests sire parentage can be unequal when semen is mixed from multiple sires. In summary, producers can expect similar pregnancy rates using single-sire and multi-sire semen, but progeny may have unequal sire representation.

Impact Of Overwinter Gain On Growth And Reproductive Performance In March-Born Heifers, Josie N. Crouch, J. Travis Mulliniks, Jacki A. Musgrave, Kacie L. Mccarthy

Nebraska Beef Cattle Reports

Summary with Implications

Heifers developed to lower rates of overwinter gain may reduce development costs without growth and reproduction impacted. A 3-year study was conducted to evaluate different overwinter rates of gain on heifer growth rates, reproductive, and economic performance. Heifers were managed together and individually supplemented (January-May) with dried distillers grains to achieve either a low (0.75 lb/d) or high (1.50 lb/d) average daily gain. At breeding, high gain heifers were heavier than low gain heifers. Average daily gain and body condition score were similar between treatments. Overwinter treatment did not impact attainment of puberty, pregnancy rates, or the …

Impact Of Pre- And Post-Breeding Supplementation On Performance Of May-Born Heifers, Josie N. Crouch, J. Travis Mulliniks, Jacki A. Musgrave, Kacie L. Mccarthy

Nebraska Beef Cattle Reports

Summary with Implications This 3-year study compared growth, reproductive performance, and economics of May-born yearling heifers that either received 2.00 lb/ heifer/ per d of a dried distillers grain supplement from pre-breeding (July) through breeding (August) or no supplement. Supplementation was offered approximately 24 days before breeding, averaging 55 days total. Heifer body weight was unaffected by supplementation. Supplementation increased average daily gain until pregnancy diagnosis, but no differences were noted after pregnancy diagnosis. Providing dried distillers grain increased the percentage of heifers that were cycling before breeding; however, no differences in pregnancy rates, percent that gave birth in the …

Interaction Of Backgrounding System And Implant Use On Growing Calf Performance, Sydney T. Vanderhoff, Braden C. Troyer, Rebecca L. Mcdermott, Mitchell M. Norman, Brandon L. Nuttelman, Galen E. Erickson, Mary E. Drewnoski, James C. Macdonald

Nebraska Beef Cattle Reports

Summary with Implications

A two-year study utilized 480 weaned steers each year targeted to gain either 1 or 2 lb/d during the winter followed by ad libitum forage intake during the summer to determine the effects of winter rate of gain and implant strategy during the winter backgrounding and summer phases on steer performance, forage intake, and compensatory gain. During the winter, steers received a Revalor-G or no implant. In the summer, steers either received a Revalor-IS or no implant. The use of Revalor-G and increased rate of gain during the winter backgrounding phase had additive effects to increase animal …

Quantifying Cereal Rye Pastures Biomass With Image Analysis, Pedro Henrique J. Fernandes, Shelby L. Davies-Jenkins, Biquan Zhao, Wei‑Zhen Liang, Mary E. Drewnoski, Yijie Xiong

Nebraska Beef Cattle Reports

Summary with Implications

By accurately assessing the amount of forage available, producers can estimate the pasture carrying capacity to make informed decisions on management. To provide producers with a feasible and efficient approach to estimate forage mass, this project evaluated performance of two image analysis tools, Crop Canopy Image Analyzer (CCIA) and Canopeo, in estimating forage mass for cereal rye. Forage mass measured by clipping the forage (areas with 5.625 ft²) was correlated with plant cover analyzed by the two tools using photos of the forage taken 37 in above the ground. Results obtained have supported the feasibility …

Impact Of Constant Versus Variable Inclusions Of Modified Distillers Grains Plus Solubles On Feedlot Cattle Performance And Carcass Characteristics, Paige M. Madison, Rebecca L. Mcdermott, Isaque F. Vicci, Joshua R. Benton, James C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

Summary with Implications

A finishing trial was conducted to evaluate the effects of varying dietary inclusion of modified distillers grains plus solubles compared to a constant inclusion throughout the entire feeding period on finishing cattle performance. Treatments were arranged as a 2 × 2 + 1 factorial with two inclusions of modified distillers grains plus solubles (10% and 25%) that were constant or varying in dietary inclusion, and a corn control (0% modified distillers grains plus solubles). Increasing the inclusion of distillers grains from 0 to 25% increased both DMI and ADG when fed at a constant inclusion of 10 …

Impact Of Full-Fat Wet Distillers Grains Inclusion In Steam-Flaked Corn Based Finishing Diets, Gatlin Hissong, Bill Dicke, Doug Smith, Andrea Watson, Galen E. Erickson

Nebraska Beef Cattle Reports

Summary with Implications

Steam-flaked corn and distillers grains are common feed ingredients in finishing rations, but the interaction between the two is not well understood. A finishing trial at a commercial feedlot using 700 calf-fed heifers was conducted to evaluate cattle performance when fed 18 or 30% (dry matter basis) full-fat wet distillers grains plus solubles in steam-flaked corn based diets with 8% roughage (hay + corn silage). No effects on cattle performance were observed due to distillers grains inclusion in the diet. Final body weight, dry matter intake, average daily gain, feed conversion, and hot carcass weight were not …

Effect Of Feeding Palm Oil On Finishing Cattle Performance, Carcass Characteristics, And Methane Production, Anna M. Kobza, Rebecca L. Mcdermott, Mitchell C. Norman, Joshua R. Benton, Long Zou, James C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

Summary with Implications

Increased demand for biofuel production has increased demand and price of commonly fed supplemental fat sources in beef operations. This finishing study evaluated the effect of feeding palm oil products on performance, carcass characteristics and methane production of feedlot finishing steers. Dietary treatments were feeding no supplemental fat or feeding one of the following fat sources at 4% of diet dry matter: whole palm oil, palm stearin, palm olein, or corn oil. Feeding supplemental fat, regardless of source, increased final body weight, average daily gain, and hot carcass weight. Feeding supplemental fat had no effect on dry …

Effect Of Feeding Two Different Feed Additives (Optipartum C+ And Prime Force) On Finishing Cattle Performance And Carcass Characteristics, Sofia Suarez-Lorences, Rebecca L. Mcdermott, Joshua R. Benton, Robert Bondurant, Willard Lemaster, James C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

Summary with Implications

A feedlot study was conducted to evaluate the effects of adding two different natural feed additives, Prime Force and Optipartum C+, on finishing cattle performance and carcass characteristics. Treatments were applied as a 2×2 factorial that included a control diet with no additive; a diet containing Prime Force; a diet containing Optipartum C+; and a diet containing both Prime Force and Optipartum C+ combined. Treatment diets were fed the last 67 d prior to slaughter as designed. Cattle fed Prime Force had greater live final body weight, carcass weight, intake, and average daily gain compared to cattle …

Effects Of Replacing Wet Corn Distillers Grains With A Purefield Distillers Grains® At 15% And 30% (Dm Basis) In Feedlot Diets, Sofia A. Canafoglia, Pablo L. Loza

Nebraska Beef Cattle Reports

Summary with Implications

A 2×2 +1 factorial experiment was performed to evaluate the effects of replacing wet corn distillers grain (WCDGS) with PureField distillers grains, a proprietary blend of wet distillers grains plus wheat middlings (Purefield LLC, Kansas, United States) at 15% or 30% of the diet (DM basis), on finishing performance and carcass characteristics. The inclusion of either byproduct resulted in improved steer performance, and carcass characteristics when compared to the treatment without the byproduct inclusion. No interactions between byproduct and inclusion level were observed for steer performance or carcass characteristics. A tendency for higher average daily gains was …

2025 Beef Cattle Report

Nebraska Beef Cattle Reports

Cow-calf Nutrition, Reproduction, and Management

Artificial Insemination of Beef Heifers with Multi-sire Semen, Dempster M. Christenson, Jordan M. Thomas, Daniel J. Kelly, Rick N. Funston

Impact of Overwinter Gain on Growth and Reproductive Performance in March- born Heifers, Josie N. Crouch, J. Travis Mulliniks, Jacki A. Musgrave, Kacie L. McCarthy

Impact of Pre- and Post-breeding Supplementation on Performance of May-born Heifers, Josie N. Crouch, J. Travis. Mulliniks, Jacki A. Musgrave, Kacie L. McCarthy

Growing Calf and Yearling Management

Effects of Allocation Frequency on Cattle Performance and Forage Utilization when Swath Grazing a Sorghum-Sudangrass Hybrid in Eastern Nebraska, Thomas E. Aquino, …

Effect Of Using Whole Soybeans, Roasted Soybeans, Or Soybean Meal In Finishing Cattle Diets, Melissa K. Bausch, James C. Macdonald, Galen E. Erickson, Pablo L. Loza

Nebraska Beef Cattle Reports

Summary with Implications

A feedlot study compared the effect of using whole or roasted soybeans at two inclusion rates (12% and 16% of diet dry matter), soybean meal, distillers grains, or a dry-rolled corn with urea control in finishing cattle diets. Steers fed the diet with the 16% inclusion of roasted soybeans had better average daily gain, feed conversion, and hot carcass weight. All other diets resulted in similar performance to the dry-rolled corn and distillers grains treatments. Roasted soybeans fed at a 16% inclusion improved F:G over the 12% roasted soybeans as compared to the whole soybeans which were …

Size Of Age-0 Sander Vitreus Pre And Post Dreissena Polymorpha Infestation On Brainerd And Bemidji Area Lakes, Quady Bernu

Journal of Earth and Life Science

Walleye Sander vitreus is the Minnesota state fish and a vital predator fish in lake ecology. Zebra mussels, Dreissena polymorpha were first found in Minnesota inland lakes in the 1980’s. These mussels have had huge impacts on water clarity as well as phytoplankton and zooplankton population levels which affect how age-0 fish feed, especially a low light feeding predator fish like walleye. A study took place on age-0 walleye size and it supported the conclusion that age-0 walleye were negatively impacted by zebra mussels in Minnesota’s large lakes. The goals of this study were to determine how the size of …

Microsatellites Reveal The Population Genetic Structure Of Yellow Perch In Minnesota, Megan Boche

Journal of Earth and Life Science

When analyzing a population’s genetic makeup, looking at variation of individuals and populations is a crucial factor. The management of yellow perch will be aided by this information particularly in regard to stocking or relocation. Microsatellite loci were used to analyze the genetic population structure of yellow perch Perca flavescens within and among 29 sampling areas throughout Minnesota’s basins. Seven microsatellite DNA loci were evaluated, with heterozygosities ranging from 0.41 to 0.78. The Lower Mississippi basin samples showed higher numbers of alleles per locus and greater expected heterozygosities compared to other basins, with Lake Pepin (PEP) exhibiting the highest average …

Marine Heatwave Response Plan For Western Australia’S Wild Capture Fisheries And Aquaculture, Department Of Primary Industries And Regional Development, Western Australia

Fisheries Management Papers

The purpose of the Western Australian wild capture fisheries and aquaculture marine heatwave response plan (the Plan) is to document the Department’s approach for identifying and responding to the hazard of a marine heatwave on wild catch fisheries (commercial, recreational, charter and customary) and aquaculture resources within the geographic boundaries of WA. It provides risk reduction strategies and establishes best-practice processes for each stage of the hazard management and response continuum, ensuring that DPIRD is able to adequately prepare for, respond to, and recover from marine heatwave events. This Plan operates in conjunction with WA’s existing aquatic resource management framework, …

Effectiveness Of Maternal Bovine Appeasing Substance Administered To Newly Received, High-Risk Stocker Calves, Elle Johnston, Rosie Whittle, Robin Cheek, Beth Kegley, Jeremy Powell, Shawna Weimer

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Stocker cattle purchased at auction can be susceptible to disease due to the stressors associated with the auction process and are referred to as “high-risk.” The objective of this study was to determine the efficacy of a maternal bovine appeasing substance, FerAppease^®, on the growth performance, health, and behavior of stocker cattle. Male beef calves (n = 80) were purchased at auction and transported to the University of Arkansas System Division of Agriculture Savoy Research Complex Beef Stocker Unit. On day 0, bulls were castrated, and steers and bulls were assigned to 8 pens (n = 10 calves/pen; …

The Comparative Effects Of A Thermal Gradient On The Age And Growth Characteristics Of Largemouth Bass (Micropterus Nigricans), And Atlantic Cod (Gadus Morhua), Whitney Hall

Theses and Dissertations

Thermal gradients impact fishes differently, due to variations in ecological niches and physiological adaptations. I assessed the effects of temperature on Largemouth Bass (Micropterus nigricans) and Atlantic Cod (Gadus morhua) using data from peer-reviewed journals, state records, and fisheries agencies. For Largemouth Bass, I analyzed the relationships between air temperature (MAT_min°C, MAT24hr°C, and MAT_max°C), and growth parameters including maximum length and weight, growth rate (K), longevity, and total length-at-ages 3, 5, and 8 years (TLAge_3,5,8), using least squares regression. Significant correlations were found between all temperature and growth metrics. Positive correlations were found between …

Genetic Analysis Of Methionine Restriction-Associated Mitochondrial Unfolded Protein Response Signaling., Josh D. Dodge

Biology Dissertations - Archive

The lifespan of an organism is dictated by various genetic and environmental factors. One such determinant is the health of mitochondria which are organelles that mediate various critical cell functions including a significant role in generating the vast supply of cellular energy. Indeed, the gradual decline of mitochondrial function is believed to be a hallmark and possible cause of aging. Paradoxically, mild mitochondrial dysfunction early in life extends lifespan in various model organisms. Cells use diverse approaches to promote mitochondrial homeostasis, including the transcriptional reprogramming of cells by mitochondrial unfolded protein response (UPRmt) to mitigate mitochondrial stress. Consistently, UPRmt activation …

Wild Horse Overpopulation- Consequences And Environmental Effects, Tessa M. Eslick Ms.

Undergraduate Theses, Professional Papers, and Capstone Artifacts

When considering wild horse overpopulation, there are many different facets of the issue that need to be addressed. Wild horse overpopulation is a significant issue across the American West, particularly on lands managed by the Bureau of Land Management( BLM). The largest populations are often found in Nevada, other states include California, Oregon, Utah, Wyoming, Washington, and Arizona. Whether there are thousands of horses on many acres of land, or hundreds spread across smaller reservations or public lands, the effects of their overpopulation remain as imminent as ever. Overpopulation is causing ecological damage and strain on resources leading to concerns …

Derivation Of The Maintenance Energy Requirements In Growing Jersey Heifers: Supplementary Table S1, Addison L. Carroll, Michael J. Vandehaar, Paul J. Kononoff

Department of Animal Science: Faculty Publications

Supplemental table for Addison L. Carroll, Michael J. VandeHaar, and Paul J. Kononoff. Derivation of the maintenance energy requirements in growing Jersey heifers. Journal of Dairy Science (2025).

Diversification Of Avifauna In The Darién Highland Region: Ecological Niche Modeling, Phylogeography And Morphology To Explore Speciation In The Montane Species Myadestes Coloratus, Chlorospingus Tacarcunae And Margarornis Bellulus., Jorge L. Garzon Vasquez Mrs

Theses and Dissertations

Montane regions in the Neotropics are hotspots of endemism and biodiversity, yet their species are especially vulnerable to the impacts of climate change and geographic isolation. This thesis investigates the evolutionary and ecological dynamics of three bird species endemic to the Darién Highlands of eastern Panama: Myadestes coloratus, Chlorospingus tacarcunae, and Margarornis bellulus. Through an integrative approach combining ecological niche modeling, morphometric analysis, and genomic data from ultraconserved elements (UCEs) and mitochondrial DNA, the study explores the historical biogeography, current distribution patterns, population structure, and phenotypic differentiation of these montane taxa. Ecological niche models revealed that suitable habitat …

Six Genera Of Ariophantidae From Bhutan (Gastropoda, Eupulmonata, Helicarionoidea), Edmund Gittenberger, Sherub, Choki Gyeltshen, Nima Dorji, Kezang Tobgay

Research outputs 2022 to 2026

Samples of the ariophantid genera Oxytesta, Bensonies, Himalodiscus, Ariophanta, Khasiella, and Sesara collected in Bhutan are treated. For all species distributional data for the kingdom are summarized on maps. Shells are described and figured on the basis of specimens from Bhutan, with radulae and genital tracts whenever possible. Six Oxytesta species are dealt with, 3 of which new to science, viz. O. delicata E. Gittenberger & Sherub, O. dubitata E. Gittenberger & Kezang Tobgay, and O. lhuentsensis E. Gittenberger & Sherub. Five Bensonies species are recognized, one of which could not be identified and 4 are described as new, viz. …

Comparing Microct Staining And Scanning Methodology For Brain Studies In Various Sizes Of Spiders, Vanessa Penna-Gonçalves, Nikolas J. Willmott, Michael B.J. Kelly, Jay R. Black, Elizabeth C. Lowe, Marie E. Herberstein

Research outputs 2022 to 2026

Recent advances in microCT are facilitating the investigation of microstructures in spiders and insects leading to an increased number of studies investigating their neuroanatomy. Although microCT is a powerful tool, its effectiveness depends on appropriate tissue preparation and scan settings, particularly for soft, non-sclerotized tissues, such as muscles, organs, and neural tissues. As the application of microCT in spiders is only in its infancy, published protocols are often difficult to implement due to substantial size variation of the specimens. The present study was initiated to determine how to account for this variation. Our work builds on previous methods using microCT …

Examining The Effects Of Songbird Nest Boxes And Habitat On Avian And Arthropod Communities In A Vineyard Ecosystem, Eleanor Macdonald

Cal Poly Humboldt theses and projects

Agricultural expansion threatens biodiversity, but integrating insectivorous birds into vineyard ecosystems may support both conservation and ecosystem services. We tested how nest boxes and habitat composition influence avian and arthropod communities in Napa Valley vineyards using a before-after, control-impact experiment across 20 sites. During the 2023-2024 breeding seasons we conducted avian point counts, sampled key pest and beneficial arthropods, and collected fecal samples from adult and nestling tree swallows (Tachycineta bicolor) and western bluebirds (Sialia mexicana) to detect vineyard pest DNA. Nest boxes significantly increased swallow and bluebird abundance within one year; swallow responses were strongest …

Environmental And Spatial Drivers Of Quillback Rockfish (Sebastes Maliger) Growth In The Northeast Pacific Ocean From California To Alaska, Claire E. Stuart

Cal Poly Humboldt theses and projects

Quillback rockfish (Sebastes maliger) are a nearshore fishery species found across the Northeast Pacific Ocean, but recent stock assessments have identified a research gap for biological growth parameters, particularly for the southern end of their range. Age-length data compiled from California to Alaska (n=34,396) was used to generate extended von Bertalanffy models with spatial, biological, and environmental covariates, specifically region, sex, depth, and an upwelling index. The objectives of this study were to explore how 1) spatial and 2) environmental covariates affect model parameters L_∞, k, and t₀. Four total models were developed: …

Jaguar (Panthera Onca) Population Status And Conservation Needs In Panama Revealed Using Spatial Density And Occupancy Models., Rebeca E. Becdach

Cal Poly Humboldt theses and projects

Jaguars (Panthera onca) are key predators and the largest felid in the Americas. The species is listed as near threatened globally due to habitat loss, fragmentation, and human persecution. Their population decline can negatively affect the structure and functioning of the ecosystems they inhabit. Conservation efforts for jaguars and their habitat require understanding jaguar populations and how they are impacted by human presence across their range. This information is lacking in Panama, a critical portion of the Jaguar range. Panama forms a narrow land bridge connecting Central and South America, integral to wildlife movement, including jaguars, across both …

Home Range, Habitat Use, And Fall Migration Of Lewis’S Woodpeckers In The Eastern Cascade Range, Oregon, Cameron Piper

Cal Poly Humboldt theses and projects

Lewis’s woodpecker (Melanerpes lewis), a burn specialist, is experiencing range-wide population declines despite increasing fire activity in the western U.S. The White River Wildlife Area in Oregon hosts the state's only year-round population, raising questions about their breeding, habitat use, and migration. In summer 2024, we tracked nine woodpeckers using telemetry to estimate home range size and overlap. Full home ranges averaged 428 ha, with 66 ha core areas, and showed evidence of growing after nesting. Home ranges overlapped extensively (Full: 91 ± 13%; Core: 63 ± 29%), though individuals had distinct areas of intense use. Males had …

Patterns Of Kinship And Sociality In North American River Otters, Whitney E. Vickers

Cal Poly Humboldt theses and projects

Previous studies of river otters (Lontra canadensis) in coastal Humboldt County, California have documented varying social group compositions over the last four decades. It has been assumed that otters travel between coastal wetland sites, but the extent of movement has been unknown. Socially, river otters have been observed alone, in small family groups that consisted of an otter mom and pup(s), in larger helper groups that consisted of an otter mom, pup(s), and at least one additional adult or juvenile (helpers), and in all-adult social groups. Until now it was unknown whether the composition of social groups was …