Animal Sciences Commons^™

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 …

Adaptation For Whom? Understanding The Impacts Of Dyke Policies On Small-Scale Farmers In Ca Mau Province Of Vietnam, Nguyen Minh Quang, Nguyen Van Minh, Nguyen Vo Chau Ngan, Martha B. Lerski

Publications and Research

Low-lying deltas worldwide are extremely vulnerable to sea-level rise. As the risks of climate-induced flooding become increasingly clear, the thirst for infrastructure-driven adaptation increases. This highlights a patent need to understand the impacts of engineering adaptation solutions, especially those targeting built structures such as dykes and sluices, on farmers from a bottom-up, farmer-centred perspective. The study addresses this call by examining cases where dyke policies, while successful in some dimensions, have undermined small-scale farmer livelihoods in Ca Mau ― Vietnam’s southernmost rural province. It identifies areas in need of attention and adds empirical data related to this group of farmers. …

Identifying Intangible And Biocultural Heritage Elements Toward Environmental Understanding: Engaging Stakeholders Through Art, Martha B. Lerski

Publications and Research

Grounded in a case study in Barbuda in the Caribbean, this research examines sustainability from the perspective of what arts and heritage can contribute to community engagement and local and broader understandings about the environment. This article documents a growing body of literature recognizing the role of arts and culture, including local knowledge and traditional ecological knowledge (TEK), in climate change endeavors. Art and TEK present expansive world views. Contextual information situates research done on the island of Barbuda pre- and post-Hurricane Irma. Visual arts workshops engaged community members in mixed methods research. Results documented cultural elements, particularly intangible and …

Gene Expression In Relation To Bone Fractures In Throughbred Racehorses, Anna M. Rauber-Ramos

Theses and Dissertations--Veterinary Science

Evidence that fractures in Thoroughbred racehorses are outcomes of chronic bone microdamage has led to extensive research into identifying horses at increased risk of fracture. This includes the use of biomarkers and messenger RNA (mRNA) as a measure of bone turnover. Previous research has found expression differences in horses with fractures compared to controls. Utilizing pre-race whole blood samples collected over an 18-month period from Thoroughbred racehorses in Southern California, RNA-sequencing was conducted on horses with bone fractures and race-matched controls to identify differences in gene expression. Focusing on third metacarpal (MC3) and proximal sesamoid bone (PSB) fractures, differentially expressed …

Impacts Of Early/Mid-Gestation Shearing On Umbilical Blood Flow And Lamb Birth Weight, Mara Johnson

Electronic Theses and Dissertations

Studies outside the USA have reported that shearing pregnant ewes during mid to late gestation increases lamb birth weight. Our hypothesis was that shearing pregnant ewes on day 50 of gestation would increase umbilical blood flow (UBF), fetal size, lambing and placental weights. Twenty-eight Polypay ewes were randomly assigned to two treatments: shorn (S) and sham-shorn (Control, CON) and divided in singleton (S: n=4; CON: n=4), twins (S: n=5; CON: n=5) and triplets (S: n=5; CON: n=5). Umbilical BF and fetal and placental measurements were obtained via ultrasonography every 10 days from day 50 to 110 of gestation. Lamb birth …

Mercury Concentrations, Health, And Marine Food Consumption Across Four Eastern Caribbean Populations: Insights From A Novel Community-Based Study, Russell Fielding, Catherine Brown, Jessica Dutton, Martin S. Forde, Heather Harewood, Lisa Hunt, Catherine Macdonald, Cameron Mewhirter, Vincent Reid, Madison Smith, Holly Taylor, Katelyn Zimmerman

Gulf and Caribbean Research

Mercury (Hg), as an environmental pollutant, can have harmful effects on human health. A common way that people are exposed to Hg is through seafood consumption. This project was designed to investigate Hg exposure through seafood consumption and its health effects among adults in 4 Caribbean countries: Barbados (n = 117), Grenada (n = 90), St. Lucia (n = 126), and St. Vincent & the Grenadines (n = 77). We applied a novel, community—based method, which involved recruiting and paying local barbers and hairstylists to collect hair samples from their clients who consented to join the project as participants. Participants …

Effect Of Forage Allocation On Steer Performance When Grazing Cereal Rye, Shelby L. Davies-Jenkins, Abigail M. Sartin, Daren D. Redfearn, Mary E. Drewnoski

Nebraska Beef Cattle Reports

Summary with Implications

Cereal rye is the most common cover crop planted today. With its good winter tolerance and rapid spring growth during a gap in perennial pasture productivity, it is an attractive forage source in early spring. Unfortunately, optimum stocking rates and how they are related to forage biomass availability are unknown. The study objective was to understand the effect of forage allowance on steer performance when rotationally grazing fall-planted cereal rye in spring. Stocking rate was negatively correlated with pounds of forage offered. Surprisingly, amount of forage offered related to average daily gain. Growing steers grazing cereal rye …

Strategies Affecting Performance And Profitability Of May-Born Steers, Dempster M. Christenson, Jacki A. Musgrave, Richard N. Funston

Nebraska Beef Cattle Reports

Summary with Implications

This study compared the performance and economic outcomes of differing backgrounding and feedlot systems in May-born yearling steers. We hypothesized reduced supplementation with adequate forage availability while backgrounding weaned steers will yield a similar carcass with greater profitability. It was hypothesized yearling steers backgrounded on pasture before finishing in feedlot would have a more valuable carcass that is more profitable than steers that enter the feedlot immediately. Weaned steer calves were backgrounded with ad libitum hay and 4 lb/d supplement in drylot or on pasture with 1 lb/d supplement. As yearlings, half of each backgrounding group immediately …

Impact Of Feeding Distillers Grains Compared To New Fractionated Distillers Grains (Solbran) On Feedlot Cattle Performance And Enteric Methane, Debora G. Sousa, Rebecca L. Mcdermott, Mitchell M. Norman, James C. Macdonald, Rick Stock, Ryan A. Mass, Galen E. Erickson

Nebraska Beef Cattle Reports

Summary with Implications

This study evaluated feeding wet or dry traditional distillers grains with wet and dry fractionated distillers (Solbran) fed at 40% of diet DM compared to a corn control diet on enteric methane emissions and performance. Compared to the control, there was no difference in carbon dioxide production, but there was an increase in methane production in the steers fed fractionated distillers compared to conventional distillers. Feeding steers traditional or fractionated distillers grains increased consumption, increased gain, but improved conversions only for steers fed WDGS, while steers fed the other distillers grains had worse or the same feed …

Assessing Reproductive Health In Zoo-Managed African Elephant Bulls (Loxodonta Africana), Kaitlyn Marie Campbell

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Populations of zoo-managed African elephant (Loxodonta Africana) exhibit substantial individual- and population-level variation in reproductive success, yet research has largely focused on females, leaving male fertility poorly understood. Subfertility in bulls, characterized by low libido and inconsistent semen quality, poses significant challenges to genetic management and long-term population sustainability. This study a) systematically evaluates semen quality, b) identifies physiological, behavioral, social, and environmental determinants of fertility, and c) advances ex situ conservation through the expansion of the African elephant sperm bank. Between January 2023 and July 2025, 209 semen collection events were conducted from 13 sexually mature bulls …

Development Of A Proposed Selective Medium For The Isolation And Differentiation Of P. Sordellii, Dimyana Bottros

Honors Undergraduate Theses

Clostridium, a genus of anaerobic, spore-forming bacteria, includes clinically and ecologically significant species like Clostridium difficile and Paeniclostridium sordellii. C. difficile causes antibiotic-associated colitis, while P. sordellii is linked to fatal infections and spontaneous abortions. Recent studies found both species in marine sediments, suggesting their role in environmental and wildlife health disturbances, including the 2013 mass mortality of over 300 manatees in the Indian River Lagoon. However, isolating and differentiating P. sordellii is challenging due to the lack of selective media optimized for its growth. This thesis proposes a novel selective medium tailored to P. sordellii’s physiological …

Validating A Novel Capability Of Assessing Pathways Of Animal Water Gain And Loss, Zachary T. Steele, Karen Caceres, Zachary A. David, Lisa M. Shollenberger, Alexander R. Gerson, Seth D. Newsome, John P. Whiteman

Biological Sciences Faculty Publications

Understanding variations in the routes by which wild animals gain and lose water is challenging, and common methods require longitudinal sampling, which can be prohibitive. However, a new approach uses Δ′¹⁷O_BW (Δ′¹⁷O of animal body water), calculated from measurements of δ′¹⁷O and δ′¹⁸O in a single sample, as a natural tracer of water flux. Δ′¹⁷O_BW is promising, but its relationship to organismal variables such as metabolic rate and water intake have not been validated. Here, we continuously measured oxygen influxes and effluxes of captive deer mice (Peromyscus maniculatus), and manipulated their water intake and metabolic rate. We used …

Hair Growth Rate Estimation In North American Ursids, Jennifer H. Stern, Karyn D. Rode, Craig A. Stricker, Sheriden Ploof, Cindy L. J. Roberts, Celess Edinger, Mary Humbyrd, Nate Wagner, Megan A. Owen, John P. Whiteman, Thea Bechshoft, Brent White, Kristin L. Laidre

Biological Sciences Faculty Publications

The feeding ecology of wildlife populations has important implications for individual health, population productivity and distribution patterns. For ursids (bears), food resources and feeding behaviour primarily affect population dynamics via effects on cub production and survival. Much of what is known about the feeding ecology of bears is based on analyses of tissues collected from capture-based research efforts, harvested animals or non-invasive approaches. However, inference about diet from hair has been limited by a lack of quantitative data on the timing of the moult and hair growth rates. We conducted a study to develop and test two methods of quantifying …

Mapping Global Research On Mycotoxins In Aquafeed From Scientometric And Critical Perspectives, Menaga Meenakshisundaram, Sudarshan Shanmugam, Jimmy B. Mboya, Felix Sugantham, Kevin Obiero, Jonathan Munguti, Sunday Ekesi, Sevgan Subramanian, Shaphan Y. Chia, Dennis Beesigamukama, Rodrigue Yossa, Chrysantus M. Tanga

All Peer-Reviewed Publications

The global significance of mycotoxins in aquaculture is evident. However, regional vulnerabilities, effects, and inconsistent regulations on mycotoxin contamination remain underexplored. This study integrates a scientometric analysis of research on mycotoxins in aquafeed, published from 1992 to 2023 in Web of Science, with a conventional review of their occurrence in aquafeed and feed ingredients. Bibliometric tools, VOSviewer, and biblioshiny, were used to analyze global research trends, collaborations, and themes. We found a total of 181 publications, authored by 938 researchers from 49 countries, with Brazil leading (25 publications). The Toxins journal accounted for the most publications (23). Aflatoxins, particularly aflatoxin …

Leukocyte Infiltration Profiles At The Site Of Intradermal Injection Of Silikon-1000 In Scleroderma-Prone Ucd200/206 And Healthy White Leghorn Chickens, Katee L. Johnson, Jossie M. Santamaria, Chrysta N. Beck, Gisela F. Erf

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

Intradermal injections of silicone-based fillers for the face and body may cause chronic inflammation and fibrotic reactions in some individuals. Chickens from the UCD 200/206 White Leghorn (WL) line spontaneously develop a fibrotic autoimmune disease known as scleroderma/systemic sclerosis (SSc). Using the SSc-prone UCD and healthy WL chickens, a longitudinal study was conducted to examine the cellular inflammatory responses to intradermal (i.d.) injections of sterile SILIKON-1000. Specifically, the pulp (a skin derivative) of growing feathers (GFs) was i.d. injected with sterile SILIKON-1000 or phosphate-buffered saline (PBS) as injection control (8 and 3 birds/line, respectively; 10 µL/GF; 20 GFs/bird). Two GFs …

Effects Of A Diet Supplemented With A Blend Of Protected Organic Acids And Essential Oilson Growth Performance And Cecal Microbiota Composition In Broilers, Mehmet Akan, Kadi̇r Serdar Di̇ker, Serdar Özlü, Murat Çelebi̇, Seyyi̇de Sariçam İnce, Barişhan Doğan, Okan Eli̇bol

Turkish Journal of Veterinary & Animal Sciences

Organic acids (OAs) and essential oils (EOs) have several positive effects on the gut microbiota of broilers. In this study, weaimed to determine the efficacy of a blend of protected OAs and EOs [P(OA+EO)] on the growth performance and cecal microbiota ofbroiler chickens. A total of 160 Ross 308 broiler chickens, including 80 male and 80 female birds, all 1 day old, were randomly distributedbetween the control group (basal diet) and the treatment group [basal diet + 300 g/t P(OA+EO)] according to an 8-pen arrangementwith 4 replicates of 20 birds. Body weight (BW), body weight gain (BWG), feed consumption (FC), …

Effects Of Ionophore And Yeast Addition To The Diet On Starch Digestion And Rumen Andblood Parameters In Sheep With Subacute Rumen Acidosis, Şevket Evci̇, Mehmet Aki̇f Karsli, Mehmet Demi̇rci̇, Gökhan Şen

Turkish Journal of Veterinary & Animal Sciences

This study aimed to investigate the prevention of acidosis in ruminants, which causes yield and financial losses, and toevaluate the effects of feed additives on starch digestion. Four male Bafra yearling lambs with cannulated rumens were used in a 60-daystudy. Each lamb underwent 10 days of adaptation to a ration and 5 days of sampling for four different rations including a control ration(CR), monensin ration (MR), Saccharomyces cerevisiae ration (SR), and a ration with the combination of monensin and Saccharomycescerevisiae (MSR). The experiment followed a 4 × 4 Latin-square design. Dry matter intake and digestion rates were recorded as 2404 …

Characterization Of The Biofilm-Forming Ability And Certain Virulence Characters Ofaeromonas Spp. Isolates From Rainbow Trout, Türker Çelebi̇, Ertan Emek Onuk, Esra Demi̇rbaş, Gökçen Di̇nç

Turkish Journal of Veterinary & Animal Sciences

Aeromonas spp., commonly found in the aquatic environment, cause infections in both fish and humans. Their pathogenicitydepends on various virulence factors and ability to form biofilm. The current study aimed to determine the biofilm-forming capabilitiesand certain virulence characteristics of 25 Aeromonas spp. isolates obtained from rainbow trout in Türkiye. The biofilm-forming abilitiesof isolates were investigated comparatively using Congo red agar (CRA), the tube method (TM), and tissue culture plates (TCPs).Potential virulence factors, including hemolytic activity, gelatinase production, serine protease activity, DNase activity, and motility,were evaluated using phenotypic tests. Additionally, the distribution of four known virulence genes, namely aerA, exu, fla, …

Administering Tolfenamic Acid To Gilts And Sows Before Artificial Insemination Did Not Improve Litter Size But Tended To Reduce Post-Service Serum Prostaglandin F2Α Levels, Pachara Pearodwong, Nithitad Jiebna, Padet Tummaruk

The Thai Journal of Veterinary Medicine

This study examined the impact of intramuscular administration of tolfenamic acid 10 min before artificial insemination (AI) on serum PGF2α levels and reproductive performance in gilts and sows. In Experiment I, 20 gilts were divided into two groups: control (n = 10) and treatment (n = 10). Serum samples were collected 30 min before and after insemination to measure PGF2α levels. In Experiment II, 175 gilts and sows were divided into control (25 gilts and 56 sows) and treatment (16 gilts and 78 sows) groups. In both experiments, the treatment group received an intramuscular injection of 2 mg/kg tolfenamic acid …