Animal Sciences Commons^™

Adapting To Uncertainty: Effects Of Environmental Instability On Zebrafish Behaviour, Britney Sekulovski

Theses and Dissertations (Comprehensive)

This thesis addresses how animals cope with unpredictability by testing how environmental stability changes the behaviour of zebrafish (Danio rerio) in two complementary experiments. In Experiment 1, fish lived for three months in either a Dynamic environment (water temperature, feeding times, habitat complexity, group size, and membership fluctuated) or a Stable environment (all factors constant). Across seven behavioural assays, measuring individual behavioural differences, collective movement, social memory, and information use, Dynamic condition fish were found to be more sensitive to social cues and more likely to conform to recent social information, independent of the quality of the information …

The Effects Of Environmental Complexity On Brain Development And Personality Expression In Western Hognose Snakes, Gokulan Nagabaskaran

Theses and Dissertations (Comprehensive)

There is growing interest in snake cognition, personality, and welfare as more snakes are kept as pets, yet little research has been conducted. The effects of enrichment and environmental factors have been well documented in other taxa, and recent evidence suggests that snakes may benefit in similar ways. This dissertation investigated the impact of environmental and social enrichment on personality expression, personality stability, and brain development. Western hognose snakes (Heterodon nasicus) were used as the model species, as they are a popular choice in the pet trade. This allows the research to be readily translatable to husbandry practices of many …

The Rna-Binding Protein Pumilio Limits Polymodal Noiception In Drosophila Larvae, Sara Palega, Hannah Davenport, Rebeccah K. Stewart, Jessica Horton, Andrew Bellemer

Microbiology & Molecular Cell Biology Faculty Publications

Nociception is the process by which the nervous system detects and processes information about potentially harmful environmental stimuli to generate behavioral and physiological responses. The process of nociception undergoes plasticity in response to injury, inflammation, and infection to shape the sensitivity of nociceptive circuits and the behavioral responses they control. We are increasingly aware that post-transcriptional regulation of gene expression shapes the sensitivity and plasticity of nociceptive sensory neurons and nociceptive behavior. In Drosophila, the Pumilio RNA-binding protein interacts with diverse target mRNAs to regulate their abundance and translation in a wide range of contexts including the establishment of …

Impacts Of Offshore Wind Energy Development On The Commercial Sea Scallop Fishery, Sarah Borsetti, Daphne M. Munroe, John M. Klinck, Andrew M. Scheld, Eileen E. Hofmann, Eric N. Powell, David B. Rudders

CCPO Publications

The Atlantic sea scallop (Placopecten magellanicus) fishery on the Northeast U.S. continental shelf generates approximately USD 500 million ex-vessel revenues annually, making it one of the most valuable single species fisheries in the United States. Wind energy development is planned for key areas on the U.S. Mid-Atlantic shelf where the Atlantic sea scallop fishery operates, creating novel challenges in managing trade-offs between traditional users like fisheries and new users like offshore wind energy. An agent-based modeling framework that integrates spatial dynamics in Atlantic sea scallop stock biology, fishing fleet behavior, and federal management decisions, was implemented to investigate …

Growing South Dakota (Winter 2026), College Of Agriculture, Food And Environmental Sciences

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

[Page] 2 International Year of Rangelands and Pastoralists: South Dakota rangelands take center stage
[Page] 4 The professor and the soil
[Page] 8 Range ready: Helping students bridge the gap between conservation and agriculture
[Page] 9 Resilient rangelands: Native Plant Initiative’s role in reviving South Dakota’s prairies
[Page] 10 Jackrabbits lead the charge in bison research and education
[Page] 12 Agricultural and biosystems engineering celebrates century of education
[Page] 16 SDSU Quarter Scale Tractor Club: An impact beyond awards
[Page] 18 Building a legacy of opportunity: Karen D. Stuck Endowment strengthens agricultural communication program at South Dakota State University
[Page] …

Intelligent Dual-Energy X-Ray Absorptiometry (Idxa) And Small Animal Scanning As A Useful Tool To Measure Appendicular Bird Bone Mineral Density, Frank J. Dirrigl Jr., Samuel R. Buchanan

School of Integrative Biological & Chemical Sciences Faculty Publications

Accurately assessing the bone mineralization status of birds is crucial for poultry production and wild bird studies. We investigated the use of dual-energy x-ray absorptiometry (DXA) using Small Animal Measurement software to measure bone mineral content (BMC) and areal bone mineral density (aBMD) in excised radii of the willow ptarmigan (Lagopus lagopus) as a bird model. Our exploratory tests involved 117 scans to evaluate scanning parameters, scanning board types, bone stabilization, scan mode and size, and region of interest placement. Results indicated that mean BMC or aBMD were each significantly different when scanned on a forearm positioner board …

Decline In Offspring Quantity But Not Quality From Successive Matings In Male Rainforest Drosophila, With No Evidence For Genetic Divergence In Male Mating Behaviour Along Elevational And Density Gradients, Andrew D. Saxon, Eleanor K. O'Brien, Natalie E. Jones, Jon Bridle

Research outputs 2022 to 2026

Fertilisation success is a major component of male fitness, meaning males should capitalise on all opportunities for mating. However, other sources of variation in fitness mean that males often evolve life histories that limit their ability to mate frequently. We quantified mating latency, mating duration, and offspring production in males of the tropical fly Drosophila birchii when presented with up to 4 females consecutively. Males were sourced from isofemale lines from the extremes of 2 elevational gradients (20–1100 m) that show substantial differences in population density, temperature, and humidity. Total offspring sired increased with number of matings achieved, demonstrating substantial …

Effects Of Particle Size Difference In Two Different Sweet Bran Products On Total Tract Digestibility And Rumen Ph, Emily K. Hoefling, Anna Kobza, Jessica L. Miller, Maggie E. Youngers, Galen E. Erickson, Jim C. Macdonald

Nebraska Beef Cattle Reports

Summary with Implications

Seven ruminally fistulated heifers were utilized in a 6 x 7 row-column design to evaluate two different Sweet Bran particle size products (1.8 or 2.5 mm) included at 13%, 18%, or 23% of the diet (DM) on total tract digestibility and rumen fermentation parameters. The treatment design was a 2 x 3 factorial. Rumen pH was reduced and organic matter digestibility tended to be reduced with the small particle size when Sweet Bran was included at 13% of the diet. Both NDF digestibility and dietary digestible energy concentration tended to improve with the larger particle size. The …

Carcass Weight Influences Chilling Rate, Postmortem Metabolism, And Beef Color, Grace C. Johnson, Mariane Beline, Leila G. Venzor, Kara A. Reynolds, Gary A. Sullivan, David E. Gerrad, Jordan C. Wicks

Nebraska Beef Cattle Reports

Summary with Implications

This study investigated the relationship between carcass weight and the development of atypical dark cutting (ATDC) beef by examining differences in chilling rates, muscle metabolism, and meat quality traits. Forty-four beef carcasses (heavy weight, HW, 510.17 ± 4.6 lb.; light weight, LW, 399.21 ± 4.6 lb.) were monitored postmortem for temperature, pH, and metabolite levels. LW carcasses cooled faster from 6 to 24 hours postmortem and exhibited higher pH at 12 hours, darker lean, and lower tenderness compared to HW carcasses. Elevated levels of glycogen and glucose-6-phosphate were observed in LW carcasses, suggesting that faster chilling may …

Effect Of Nitrite Source & Reducing Compounds On Cured Color Development In An All-Beef Model System, Leila G. Venzor, Grace C. Johnson, Ashley A. Hahn, Benjamin L. Weinandt, Jordan C. Wicks, Gary A. Sullivan

Nebraska Beef Cattle Reports

Summary with Implications

This study evaluated the effects of nitrite source (sodium nitrite, celery powder, beet powder) and reducing agents (none, sodium erythorbate, acerola) on cured color development, cured meat pigment formation, and residual nitrite in an all-beef emulsion as a model system for frankfurters and smoked sausage. Treatments were prepared and analyzed for color, pigment concentration, and nitrite retention. Nitrite source did not significantly affect cured pigment or residual nitrite. The inclusion of reducing compounds significantly increased cured pigment and redness in cooked samples while lowering residual nitrite. No treatment differences were found for initial raw color. These results …

Evaluation Of Herddogg Remote Sensing Tag On Detection Of Morbidity Of Newly Received Steers, Lauryn O. Smidt, Rebecca Mcdermott, Jessica L. Sperber, Josh R. Benton, Galen E. Erickson, Jim C. Macdonald

Nebraska Beef Cattle Reports

Summary with Implications

A receiving study was conducted to evaluate the HerdDogg remote sensing tag for the detection of morbidity in newly received steers. Treatments were assigned to cattle in the order they came through the chute, and those included a treatment whereby pen-riders evaluated the cattle and made the decision on when to treat (Pen-Rider), compared to the HerdDogg remote sensing ear tag that solely identified and flagged cattle in need of treatment (TAG). Cattle were fed for 41 days before being weighed off the receiving trial. While no differences in performance were observed, the TAG treatment had a …

Use Of Virtual Fences To Co-Fence Two Groups Of Cattle With Adjacent Virtual Boundaries, Thomas E. Aquino, Mary E. Drewnoski, Biquan Zhao, Pedro Henrique Jota Fernandes, Isaque F. Vicci, Mitchell B. Stephenson, Yijie Xiong

Nebraska Beef Cattle Reports

Summary with Implications

While virtual fencing (VF) has proven effective in managing cattle, limited data exist on using it to manage two separate groups of cattle within the same area. If successful, this approach could reduce infrastructure costs and increase management flexibility. In this trial, VF-trained steers (n = 39) were placed in pastures with either no neighboring cattle (isolated) or next to a separate group with only a VF boundary between them (co-fenced). Containment exceeded 99% across all cattle, demonstrating that VF creates effective boundaries regardless of fence treatment. There was no statistical difference in the number of audio …

Application Of High-Pressure Processing Lightens The Color Of Cow Tenderloins, Kara A. Reynolds, Leila G. Venzor, Ashley A. Hahn, Grace C. Johnson, Jordan C. Wicks, Mary-Grace C. Danao, Ranjith Ramanathan, Gary A. Sullivan

Nebraska Beef Cattle Reports

Summary with Implications

This study evaluated the impact of high-pressure processing (HPP) on color, oxidative stability, and tenderness of tenderloins (psoas major) from cull cows to determine if HPP could enhance their marketability. Forty cull cow tenderloins were treated at two different HPP pressures and two different holding times, then assessed for instrumental and visual color, lipid oxidation, and Warner-Bratzler shear force during a 7-day stimulated shelf period. HPP increased initial lightness, especially at the highest pressure and longest holding time and improved redness initially. However, redness declined, and discoloration increased over the 7-day period, particularly after processing at higher …

Using High-Pressure Processing To Improve Dark-Cutting Beef Color In Tenderloins, Ashley A. Hahn, Leila G. Venzor, Shelley A. Curry, Grace C. Johnson, Mary-Grace C. Danao, Ranjith Ramanathan, Gary A. Sullivan, Jordan C. Wicks

Nebraska Beef Cattle Reports

Summary with Implications

Dark-cutting beef is a quality defect that negatively impacts consumer appeal and affects the carcass value for both producers and meat processors. These economic losses stem from poor visual appearance and reduced consumer appeal in the retail setting. Notably, different muscles within a carcass exhibit varying degrees of color stability which can influence how dark-cutting manifests across cuts. Therefore, this study aimed to examine the effect of high-pressure processing (HPP) on dark-cutting color-labile muscle. Dark-cutting and normal tenderloins were collected and portioned into two equal sections. Dark-cutting tenderloins were assigned one of 3 treatments: No HPP, 300 …

Defining The Parameters Of High-Pressure Processing To Improve The Quality Of Dark-Cutting Beef, Ashley A. Hahn, Leila G. Venzor, Shelley A. Curry, Grace C. Johnson, Mary-Grace C. Danao, Ranjith Ramanathan, Jordan C. Wicks, Gary A. Sullivan

Nebraska Beef Cattle Reports

Summary with Implications

Dark-cutting beef is a result of preharvest stress and devalues the resulting carcass. High-pressure processing (HPP) has been recently identified as a potential strategy to improve the undesirable appearance of dark-cutting beef. Dark-cutting beef strip loins were collected from a local processing facility, sectioned, and assigned an HPP pressure (300 or 450 MPa) and holding time (0, 1, 30, 60, or 90 s). Overall, HPP increased the lightness and redness of dark-cutting beef, particularly the longer the pressure was held at both pressure levels. Additionally, negative effects such as increased meat discoloration, decreased tenderness, and increased rancidity …

Evaluating Sorghum X Sudangrass Seed Digestibility, Evan Blank, Thomas E. Aquino, Mary E. Drewnoski

Nebraska Beef Cattle Reports

Summary with Implications

A sorghum-sudangrass hybrid was swathed in the hard dough stage and grazed by growing steers from November 2023 to January 2024. Steers appeared to select the seedheads when grazing. The seed made up approximately 12.6% of swathed forage mass, but its energy contribution appears limited due to poor digestibility. When incubated whole, only 23% of dry matter and 13% of starch was digestible. Grinding improved digestibility but still left 40% of the dry matter and over 85% of starch unavailable. Weathering over two months did not improve digestibility, indicating the seed coat remains intact through winter. Compared …

Long-Term Trends Of Annual Herbaceous Expansion In The Nebraska Panhandle: Rangeland Analysis Platform Data, Karley Dieckmann, Mitchell B. Stephenson, Miranda Mueller

Nebraska Beef Cattle Reports

Summary with Implications

This descriptive analysis evaluated changes in Annual Forb and Grass (AFG) herbaceous cover in the Nebraska Panhandle from 1986 to 2023 using the Rangeland Analysis Platform (RAP). It was hypothesized that AFG herbaceous cover would show an increasing trend over time, indicating the potential expansion of the annual invasive cheatgrass (Bromus tectorum). County-level RAP data were used to calculate long-term means as an indicator. Results showed an increase in AFG cover across the region. Trends were cyclical, with cover peaking and dipping over time, but the overall trajectory showed increases in AFG in the Panhandle. The increasing …

Impact Of Feeding Palm Oil To Finishing Cattle On Performance, Carcass, And Meat Characteristics, Tate S. Johnson, Rebecca L. Mcdermott, Josh R. Benton, Galen E. Erickson, Jessie C. Morrill, Jim C. Macdonald

Nebraska Beef Cattle Reports

Summary with Implications

This finishing study evaluated the effect of feeding palm oil products on performance and carcass characteristics, and beef quality measures. Dietary treatments included no supplemental fat or feeding: crude palm oil, crude high-oleic palm oil (HOPO), refined, bleached, and de-odorized palm olein oil (RBD olein), or tallow. Supplemental fat was included at 3.5% of diet dry matter. Cattle fed diets containing supplemental fat had improved feed conversion compared to no supplemental fat. Feeding cattle crude palm oil resulted in improved F:G compared to cattle fed RBD olein, with steers fed tallow and crude HOPO being intermediate and …

Comparison Of Spayed Heifer Performance To Intact Heifers Fed Melengestrol Acetate On Feedlot Performance And Carcass Characteristics, Tate S. Johnson, Rebecca L. Mcdermott, Halden J. Clark, Jim C. Macdonald, Jessica L. Sperber

Nebraska Beef Cattle Reports

Summary with Implications

Pregnancy and estrous cycle management are critical considerations when feeding intact heifers in the feedyard. Alternatively, producers can opt to spay heifers, which eliminates hormonal fluctuations associated with the estrous cycle. A proportion of U.S. feedlots have spayed heifers on feed, although there is limited data comparing the performance of spayed heifers to intact heifers. A commercial feedlot experiment was conducted to compare performance between spayed and intact heifers fed melengestrol acetate. Intact heifers had greater ADG and tended to have greater DMI compared to spayed heifers, although no difference in feed conversion was observed. Carcass weight …

Summary Of The Value Of Distillers Grains Plus Solubles For Feedlot Cattle, Rebecca L. Mcdermott, Jim C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

Summary with Implications

An analysis of over 6,100 head of finishing cattle across 50 experiments was conducted to determine the feeding value of full-fat and de-oiled distillers grains. This analysis was limited to studies where dry-rolled corn, high-moisture corn, or a combination of the two corn processing methods were displaced by 15% or more distillers grains. Dry distillers grains plus solubles (DDGS), modified distillers grains plus solubles (MDGS), and wet distillers grains plus solubles (WDGS) were evaluated as either full-fat or de-oiled. The feeding value of distillers grains was assessed relative to a corn-based control diet containing no distillers. Results …