Large or Food Animal and Equine Medicine Commons^™

Impact Of Corn Silage Inclusion On Finishing Cattle Performance, Hannah C. Hamilton, F. Henry Hilscher, Zachary E. Carlson Carlson, Brad M. Boyd, Andrea K. Watson, Jim C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

Cattle fed high grain diets with little to no roughage are typically at greater risk for acidosis and reduced dry matter intake and average daily gain. An individual feeding study was conducted to compare different inclusions of corn silage used as a roughage source on finishing performance and liver abscess rate. Treatments consisted of 3 inclusions of corn silage at 0, 7.5 and 15% of the diet DM and a control treatment with 7.5% alfalfa. There were no differences for live animal performance or carcass characteristics. There were also no differences in liver abscess incidence. Feeding corn silage at 15% …

Bovine Cellular And Innate Immune Response To Hemostatic Polysaccharides, Brian Kobylkevich

Electronic Theses and Dissertations

Chronic wounds are longstanding dermal wounds that do not heal in a normal amount of time and can commonly last for over a year. These wounds plague humans and farm animals alike. Wounds are characterized by chronic inflammation and are often painful, difficult to heal, have a high recurrence rate, and are potentially debilitating. Long term wounds that do not fully heal are distressing for both humans and animals, but understandably more resources have been directed towards humans. Some treatment options for humans may be suitable for adaptation into the field of animal care. Chronic lesions such as bovine digital …

Effects Of Urea And Distillers Inclusion In Finishing Diets On Steer Performance And Carcass Characteristics, Bradley M. Boyd, James C. Macdonald, Matthew K. Luebbe, Galen E. Erickson

Nebraska Beef Cattle Reports

An experiment was conducted to evaluate the effect of supplemental urea in dry rolled corn based finishing diets containing low inclusions of distillers grains. Treatments were set up in a 3 × 3 factorial arrangement. The first factor was wet distillers inclusion at either 10, 15, or 20% of diet DM. The second factor was urea inclusion at either 0, 0.5, or 1.0% of diet dry matter. Increasing inclusion of distillers linearly improved feed conversion and linearly reduced dry matter intake. An interaction for feed efficiency was observed where there was no effect of added urea when 10% or 20% …

Evaluation Of The Energy Value And Nutrient Digestibility Of Distillers Grains That Have Undergone A Fiber Separation Process In Finishing Diets, Shelby A. Garland, Melissa L. Jolly-Breithaupt, Hannah C. Hamilton Hamilton, Galen E. Erickson, James C. Macdonald, Ryan A. Mass

Nebraska Beef Cattle Reports

A digestion study was conducted to determine the effects of feeding a new, high protein distillers grains and corn bran plus solubles on nutrient digestibility. Treatments included a corn-based control, high protein distillers at both 20% and 40%, corn bran plus solubles, traditional wet distillers grains and traditional dry distillers grains all at 40% of diet DM. Feeding high protein distillers grains or corn bran plus solubles resulted in decreased digestibility compared to corn or traditional wet and dry distillers grains, but increased energy intake. Traditional wet and dry distillers grains also resulted in decreased digestibilities while energy intake was …

Evaluation Of An Algal Biomass As An Ingredient In Cattle Feed, Mitchell M. Norman, Zachary E. Carlson, F. Henry Hilscher Hilscher, Andrea K. Watson, Galen E. Erickson, Bruce W. Brodersen, J. Dustin Loy, Jonathan W. Wilson

Nebraska Beef Cattle Reports

A study was conducted evaluating the effects of feeding condensed algal residue solubles (CARS; available in 2019 in Blair, NE area) to finishing cattle for 100 days. Four levels of CARS were evaluated with 5 steers and 5 heifers individually fed per level of inclusion. The diets consisted of 70% dry rolled corn with CARS displacing corn at 0, 2.5, 5, and 7.5% of dry matter. Increasing CARS inclusion resulted in a linear decrease in intake, a quadratic increase in daily gain, and a linear decrease in feed:gain. Calculations showed a linear increase in dietary net energy as …

Evaluation Of Reimplant Window With Revalor-200 ® On Steer Performance And Carcass Characteristics, Caitlin A. Ohnoutka, Brad M. Boyd, F. Henry Hilscher Hilscher, Brandon L. Nuttelman, Grant I. Crawford, Jim C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

A feedlot study utilizing 800 crossbred steers (initial BW = 727 ± 55 lb) compared 5 different terminal implant (Revalor-200) times (160, 120, 100, 80, or 40 d prior to harvest) for steers fed 180 days on performance and carcass characteristics. All steers were implanted with Revalor-IS as an initial implant at trial initiation. Carcass-adjusted final BW, ADG, and F:G responded quadratically, with cattle implanted 80 to 120 d prior to harvest being the greatest. However, there was less than a 2% difference in performance between 120 and 80 days on terminal implant. Hot carcass weight responded quadratically, with no …

Effects Of Backgrounding And Feedlot System Strategies On May-Born Steer Performance, Alicia C. Lansford, Jacki A. Musgrave, T. L. Meyer, Rick N. Funston

Nebraska Beef Cattle Reports

May-born steers were backgrounded to achieve either a high or low rate of gain. The high rate of gain was achieved by offering steers meadow hay ad libitum and 4 lb/d of a 33% CP (DM) supplement, while the low rate of gain consisted of steers grazing meadow and offered 1 lb/d of the same supplement. After backgrounding, one-half of the steers from each group entered the feedlot in May as short-yearlings, while the remainder grazed upland range until entering the feedlot as long-yearlings in mid-September. Hot carcass weight was greater for steers backgrounded to achieve a high rate of …

The Effect Of Bovine Galectin-1, A Conceptus Secretory Protein, On The Endometrial Transcriptome, Lindsay Faye Grose

Graduate Theses, Dissertations, and Problem Reports (ETD)

Early embryonic loss in cattle is detrimental to reproduction thus, the profitability of both the beef and dairy industries. Therefore, an important aspect of study is to find techniques that beef or dairy producers could use to decrease early embryonic loss Galectin-1, the protein that was investigated in this research is important in modulating the maternal immune system in rodent and human early pregnancies by promoting fetomaternal immune tolerance. The role of galectin-1 within the reproductive tissues has not been thoroughly investigated in cattle. Galectin-1 is located in the caruncular and intercaruncular regions of the bovine endometrium, specifically the maternal …

Kinetics Of The Chromosome 14 Microrna Cluster Ortholog And Its Potential Role During Placental Development In The Pregnant Mare, Pouya Dini, Peter Daels, Shavahn C. Loux, Alejandro Esteller-Vico, Mariano Carossino, Kirsten E. Scoggin, Barry A. Ball

Maxwell H. Gluck Equine Research Center Faculty Publications

Background: The human chromosome 14 microRNA cluster (C14MC) is a conserved microRNA (miRNA) cluster across eutherian mammals, reported to play an important role in placental development. However, the expression kinetics and function of this cluster in the mammalian placenta are poorly understood. Here, we evaluated the expression kinetics of the equine C24MC, ortholog to the human C14MC, in the chorioallantoic membrane during the course of gestation.

Results: We demonstrated that C24MC-associated miRNAs presented a higher expression level during early stages of pregnancy, followed by a decline later in gestation. Evaluation of one member of C24MC (miR-409-3p) by in situ hybridization …

Improved Reference Genome For The Domestic Horse Increases Assembly Contiguity And Composition, Theodore S. Kalbfleisch, Edward S. Rice, Michael S. Depriest Jr., Brian P. Walenz, Matthew S. Hestand, Joris R. Vermeesch, Brendan L. O'Connell, Ian T. Fiddes, Alisa O. Vershinina, Nedda F. Saremi, Jessica L. Petersen, Carrie J. Finno, Rebecca R. Bellone, Molly E Mccue, Samantha A. Brooks, Ernest Bailey, Ludovic Orlando, Richard E. Green, Donald C. Miller, Douglas F. Antczak, James N. Macleod

Maxwell H. Gluck Equine Research Center Faculty Publications

Recent advances in genomic sequencing technology and computational assembly methods have allowed scientists to improve reference genome assemblies in terms of contiguity and composition. EquCab2, a reference genome for the domestic horse, was released in 2007. Although of equal or better quality compared to other first-generation Sanger assemblies, it had many of the shortcomings common to them. In 2014, the equine genomics research community began a project to improve the reference sequence for the horse, building upon the solid foundation of EquCab2 and incorporating new short-read data, long-read data, and proximity ligation data. Here, we present EquCab3. The count of …

Establishing Hematology And Serum Chemistry Reference Intervals For Wild Hawaiian Monk Seals (Neomonachus Schauinslandi), Angela C. Kaufman, Stacie J. Robinson, Dori L. Borjesson, Michelle Barbieri, Charles L. Littnan

United States Department of Commerce: Staff Publications

Hematology and serum chemistry reference intervals have been previously established for the endangered Hawaiian monk seal (Neomonachus schauinslandi) as an imperative measure for health assessments. Monitoring the health of the wild population depends upon reference intervals that are context specific; hence we developed reference intervals from fresh samples, as opposed to frozen, from wild monk seals. This study builds on the number of parameters from previous efforts by using samples collected between 2004 and 2015 from wild monk seals. Blood samples were analyzed by a single veterinary diagnostic laboratory within 24 hr of collection from apparently healthy, wild …

Genomic Approaches To Identify Important Traits In Avian Species, Bhuwan Khatri

Graduate Theses and Dissertations

This dissertation focusses on identifying different molecular markers that have impact on overall poultry production. Chapter one reviews microRNA (miRNA), copy number variation (CNV) and single nucleotide polymorphism (SNP) as markers suggested in different avian species by various studies. It reviews modern genomic approaches that are employed for next generation sequencing data analysis and verification.

Chapter two seeks to identify and validate the muscle specific miRNAs in the breast muscle of modern broilers and its foundational chicken line. Small RNA sequencing was performed to identify differentially expressed mature miRNAs in the breast muscles of these two chicken lines. Results showed …

Kisspeptin Modulates Luteinizing Hormone Release And Ovarian Follicular Dynamics In Pre-Pubertal And Adult Murrah Buffaloes, Vishalkumar Pottapenjera, Srinivasa R. Rajanala, Chandrasekhar Reddy, Arunakumari Gangineni, Kiran Avula, Sandeep K. Bejjanki, Sriravali Sathagopam, Surabhi Kesharwani, Sathya Velmurugan

Pharmacology and Nutritional Sciences Faculty Publications

Kisspeptin is a neuropeptide that governs the reproductive axis upstream to GnRH. We wanted to study whether kisspeptin modulates plasma LH and FSH levels and ovarian follicular dynamics in buffaloes and whether kisspeptin can be used for fixed time artificial insemination (FTAI). We carried out these studies in comparison with buserelin, a potent GnRH agonist. Kisspeptin dose-dependently increased plasma LH levels. However, the kisspeptin-induced increase in LH was short-lived as the peak reached in 15–30 min returned to basal values by 1–2 h. The kisspeptin-induced increase in LH level was less compared to buserelin-induced increase in LH level which sustained …

Downregulation Of Microrna Eca-Mir-128 In Seminal Exosomes And Enhanced Expression Of Cxcl16 In The Stallion Reproductive Tract Are Associated With Long-Term Persistence Of Equine Arteritis Virus, Mariano Carossino, Pouya Dini, Theodore S. Kalbfleisch, Alan T. Loynachan, Igor F. Canisso, Kathleen M. Shuck, Peter J. Timoney, R. Frank Cook, Udeni B. R. Balasuriya

Maxwell H. Gluck Equine Research Center Faculty Publications

Equine arteritis virus (EAV) can establish long-term persistent infection in the reproductive tract of stallions and is shed in the semen. Previous studies showed that long-term persistence is associated with a specific allele of the CXCL16 gene (CXCL16S) and that persistent infection is maintained despite the presence of a local inflammatory and humoral and mucosal antibody responses. In this study, we demonstrated that equine seminal exosomes (SEs) are enriched in a small subset of microRNAs (miRNAs). Most importantly, we demonstrated that long-term EAV persistence is associated with the downregulation of an SE-associated miRNA (eca-mir-128) and with an enhanced …

Effects Of Kernel Processing At Harvest Of Brown Midrib Corn Silage On Finishing Performance Of Steers, Lauren A. Ovinge, F. Henry Hilscher, Curtis J. Bittner Bittner, Bradley M. Boyd, John N. Anderson, Galen E. Erickson

Nebraska Beef Cattle Reports

A 2 × 3 factorial finishing study evaluated kernel processing in three corn silage hybrids on finishing performance of yearling steers fed 40% silage. The three hybrids included a control corn silage (CON), a brown midrib (bm3), and a brown midrib with a softer endosperm (bm3-EXP). No interactions were observed between hybrids and kernel processing (P > 0.45). Feeding both bm3 hybrids increased dry matter intake and average daily gain over CON (P < 0.01). Cattle fed bm3-EXP and bm3 had lower feed to gain than CON (P = 0.04), with no differences between the two brown midrib hybrids. Feeding silage that has undergone kernel processing decreased dry matter intake with similar average daily gain, which decreased feed to gain by 2.6% at 40% inclusion compared to non-processed silage (P = 0.10). The improvement in silage is calculated to be 6.5% (2.6/40) when kernel processing was utilized as compared to not kernel processing the corn silage hybrids.

Impact Of Ramaekers Immune Primer On Finishing Beef Cattle Performance And Liver Abscess Rate, Hannah C. Wilson, F. Henry Hilscher, Bradley M. Boyd Boyd, Jim C. Macdonald, Galen E. Erickson

Nebraska Beef Cattle Reports

A feedlot study was conducted comparing a natural feed additive (Ramaekers Immune Primer) to Tylan or nothing on receiving and finishing performance. There were no differences for final BW, ADG, F:G, HCW, marbling, LM area, or fat thickness due to treatment. Liver abscess incidence and severity were reduced in steers fed Tylan, no differences were noted between Ramaekers Immune Primer and no additive. There was no difference in number of cattle treated for respiratory illness. Steers on the Ramaekers Immune Primer treatment had lower feed intake during the receiving period but had similar ADG and numerically better F:G at day …

Effect Of Backgrounding System On Performance And Profitability Of Yearling Beef Steers, Cody A. Welchons, Robby G. Bondurant, F. Henry Hilscher Hilscher, Andrea K. Watson, Galen E. Erickson, Jim C. Macdonald

Nebraska Beef Cattle Reports

Five summer management strategies were compared following grazing corn residue through winter. Cattle were assigned to be 1) summer finished, 2) graze bromegrass, 3) graze bromegrass and fed distillers grains at 0.6% of BW, 4) backgrounded in a drylot pen to gain 1.70 lb/d, or 5) backgrounded in a drylot pen to gain 2.35 lb/d. Results differed by year, however, in general as backgrounding ADG increased, days required on feed to reach an equal fat endpoint decreased. In year 1, ADG of cattle grazing bromegrass was less than cattle backgrounded in pens. There was no difference in finishing ADG for …

Effect Of Continuous Or Rotational Grazing On Growing Steer Performance And Land Production, Cody A. Welchons, Robby G. Bondurant, F. Henry Hilscher Hilscher, Terry J. Klopfenstein, Andrea K. Watson, Jim C. Macdonald

Nebraska Beef Cattle Reports

Individual animal performance and animal production per acre were evaluated for steers grazing smooth bromegrass over 2 consecutive years. Treatments consisted of steers continuously grazing smooth bromegrass and initially stocked at either 4.0 animal unit months (AUM)/ac (HI) or 2.8 AUM/ac (LO) or steers rotationally grazing smooth bromegrass and initially stocked at 4.0 AUM/ac (ROT). Average calculated stocking rate for the LO, HI, and ROT treatments was greater than initial stocking rates due to the use of put and take animals. In vitro organic matter digestibility and crude protein of rotationally grazed pastures was relatively constant as the grazing season …

Effects Of Movement And Activity Behavior In A Pasture System Compared To Time, Jace R. Stott, Mitchell B. Stephenson, Kathryn J. Hanford Hanford

Nebraska Beef Cattle Reports

During the summer of 2016 seventeen cows were fitted with Global Positioning System (GPS) tracking collars to evaluate activity characteristics of cattle on rangelands. Data collected included daily distance traveled, average distance from water, daily time spent at water, daily area covered, and percent of day spent active (traveling or grazing). These variables were analyzed weekly to assess changes in behavior as time within pastures increased during three time periods of the growing season. Based on data collected from mid-May to mid-September, cattle showed little changes throughout the grazing season as to levels of activity through different periods of a …

Statistics Used In The Nebraska Beef Report And Their Purpose

Nebraska Beef Cattle Reports

The purpose of beef cattle and beef product research at UNL is to provide reference information that represents the various populations (cows, calves, heifers, feeders, carcasses, retail products, etc) of beef production. Obviously, the researcher cannot apply treatments to every member of a population; therefore he/ she must sample the population. The use of statistics allows the researcher and readers of the Nebraska Beef report the opportunity to evaluate separation of random (chance) occurrences and real biological effects of a treatment. Following is a brief description of the major statistics used in the beef report. For a more detailed description …

Impact Of Winter Supplementation Of May Calving Cows And Heifer Development System In Two Different Breeding Seasons On Subsequent Growth And Reproduction, Shelby A. Springman, Alicia C. Lansford, Jacqueline A. Musgrave Musgrave, John Nollette, Andy Applegarth, Richard N. Funston

Nebraska Beef Cattle Reports

In Exp. 1, May-calving cows were utilized to evaluate the effects of winter supplementation on heifer progeny. Cows grazed either dormant upland winter range with or without a protein supplement or grazed dormant meadow with or without a protein supplement. In Exp. 2, replacement heifers from March and May calving herds were offered ad libitum meadow hay and 4 lb/d supplement or grazed meadow and offered 1 lb/d supplement from mid-January to mid-April. Calf weaning BW and ADG from birth to weaning was less for calves from cows grazing winter range with no supplement compared with all other dam treatments. …

Effect Of Injectable Trace Mineral On Reproductive Performance In Beef Heifers, Shelby A. Springman, John Maddux, Mary E. Drewnoski Drewnoski, Richard N. Funston

Nebraska Beef Cattle Reports

Trace minerals serve an essential role in regulating reproduction. Free-choice trace mineral supplementation is often provided to grazing beef cattle. An injectable trace-mineral solution used with free-choice trace minerals may be beneficial before breeding to improve mineral status. Therefore, Red Angus-based, May-born heifers were utilized to determine the effects of an injectable trace mineral on reproductive performance. Pregnancy rates did not differ between heifers injected with a trace mineral and heifers that received no injection. Injectable trace mineral at CIDR insertion 33 d before artificial insemination did not influence reproductive performance in heifers with adequate trace mineral status.

Evaluating Methods Of Estimating Forage Intake By Grazing Cattle, Aaron J. Shropshire, Walter H. Schacht, Jerry D. Volesky Volesky

Nebraska Beef Cattle Reports

Two methods of estimating forage intake of grazing cattle were compared to clipped estimates in 4-pasture rotational grazing systems on Sandhills subirrigated meadow from mid-May through early August over a 4-year period. Clipping standing vegetation samples within a pasture before and after cattle grazing provides for an accurate estimate of forage removal during a grazing period. A less laborious method of intake estimation commonly used is based on a percentage of an animal’s liveweight. University Extension and some federal agencies use a 2.3% factor and others such as the Natural Resources Conservation Service use a 2.7% factor. In this study …

Letrozole: A Steroid-Free Estrous Synchronization Method, Sarah M. Romereim, Sarah C. Tenley, Mohamed A. Abedal-Majed Majed, Jeffrey W. Bergman, Scott G. Kurz, John S. Davis, Jennifer R. Wood, Andrea S. Cupp

Nebraska Beef Cattle Reports

Most bovine estrous synchronization protocols utilize progesterone plus estrogen to control ovulation timing. A drug that inhibits estrogen production (Letrozole) may be an alternative, steroid-free synchronization method (not yet commercially available). However, low estrogen can negatively affect the health of follicles/oocytes and impact fertility. To determine its effects, Letrozole was administered intramuscularly while tracking follicle growth and circulating hormones. Letrozole response was variable. Two of three cows experienced delayed luteolysis/ovulation and extended progesterone production. This preliminary data indicates that Letrozole treatment allows normal follicle progression but drug response may vary and little is known about effects on oocyte quality.

Impact Of Dietary Fat Source On Beef Display Life, Felipe A. Ribeiro, Katherine I. Domenech-Perez, Emery K. Wilkerson Wilkerson, Hope Voegele, Nicolas J. Herrera, Kellen B. Hart, Chris R. Calkins

Nebraska Beef Cattle Reports

This study was conducted to evaluate the effects of dietary fat source with modified distillers grains plus solubles (MDGS) on beef display life. Steers were fed either a corn control, full-fat MDGS, de-oiled MDGS, or de-oiled MDGS plus corn oil diet. Strip loins were aged for 2, 9, 16 and 23 days and placed under retail conditions for 7 days. Results suggest that feeding MDGS to cattle increases polyunsaturated fatty acid content of beef and has the potential to reduce beef color and lipid stability in comparison to corn diets. These data indicate that feeding MDGS to cattle may decrease …

Using A Cured Meat Model System To Investigate Factors That Influence Cured Color Development, Jennifer A. Posthuma, Faith D. Rasmussen, Gary A. Sullivan Sullivan

Nebraska Beef Cattle Reports

Producing cured meats manufactured with natural ingredients could impact cured meat characteristics, including color. The objective of this study was to determine the effects of nitrite source (sodium nitrite or cultured celery juice powder), reducing agents (no reducing compound or sodium erythorbate/ ascorbic acid), and holding times prior to cooking on cured color development in a meat model system. The addition of reducing compounds had the largest impact on cured color development and reduced residual nitrite in a cured meat model system. Treatments cured with sodium nitrite had slightly greater cured color development than treatments cured with celery juice powder. …

Repeated Calm Handling Can Lead To More Docile Cattle, Jamie T. Parham, Amy E. Tanner, Mark L. Wahlberg Wahlberg, W. S. Swecker Jr., Ronald M. Lewis

Nebraska Beef Cattle Reports

Changes in temperament in heifers when handled either frequently or infrequently were evaluated subjectively based on their behavior when restrained in (chute score) and exiting from (exit score) a squeeze chute. Chute scores decreased over time–a favorable direction–with more dramatic declines in heifers handled more frequently. Heifers with higher chute scores on the first day of handling had the largest reduction in score. Exit scores changed less over time. Chute score therefore may be more indicative of acclimation to a novel environment than exit score. Both scores appear to offer a fast, easy and inexpensive way to quantify docility in …

Rumen Undegradable Protein Content And Digestibility Of Corn Silage And High-Moisture Corn, Colton R. Oney, Jana L. Gramkow, F. Henry Hilscher Hilscher, Elizabeth Schumacher, Andrea K. Watson, Galen E. Erickson, Jim C. Macdonald, Terry J. Klopfenstein

Nebraska Beef Cattle Reports

Two studies were conducted to determine rumen undegradable protein (RUP) content and digestibility in corn silage. In Exp. 1, 37 and 42% DM corn silage were incubated in situ with two ruminally and one duodenally cannulated steer to calculate RUP content and RUP digestibility. In Exp. 2, dry rolled corn was reconstituted to 75, 70, 65, and 50% DM and ensiled in mini silos for 30, 90, 180, or 270 days. After ensiling, samples were ruminally incubated to determine RUP content of the grain. The grain within corn silage is less than 50% DM, as moisture content increases and time …

The Effect Of Inoculants On Nutrient Losses Of Corn Silage And High-Moisture Corn Stored In Mini Silos, Colton R. Oney, Jana L. Gramkow, Andrea K. Watson Watson, Galen E. Erickson, Jim C. Macdonald, M. K. Biddlecome

Nebraska Beef Cattle Reports

Two experiments were conducted to determine the effects of inoculants (BONSILAGE CORN 200G and BONSILAGE HMC 200G) containing Lactobacillus buchneri, Lactobacillus plantarum and Pediococcus acidilactici on nutrient losses and aerobic stability of corn silage and high moisture corn. Corn silage and high moisture corn were inoculated and stored in mini silos with nutrient loss and spoilage characterizations at 30, 90, and 120 days with multiple inoculation levels. Longer ensiling times led to greater total acid production. The higher levels of inoculation led to lower total acid production and higher pH. Inoculating corn silage and high moisture corn also affected …

Effect Of Revalor-Xr And Revalor-Xh On Heifer Performance And Carcass Characteristics, Caitlin A. Ohnoutka, Bradley M. Boyd, F. Henry Hilscher Hilscher, Grant I. Crawford, Brandon L. Nuttleman, Galen E. Erickson

Nebraska Beef Cattle Reports

A feedlot study evaluated the effects of 4 implant strategies (Revalor-XR on day 1, Revalor-XH on day 1, Revalor-200 on day 1, and Revalor-200 on day 70) on growth performance and carcass characteristics of feedlot heifers compared to non-implanted heifers fed 198 days. Intake was not impacted by treatments. Implanted cattle had greater carcass-adjusted ADG and lower F:G compared to cattle that received no implant. Implanted treatments had significantly greater HCW, dressing percentages, and lower marbling scores compared to non-implanted cattle. Heifers implanted with Revalor-XR, Revalor-XH, and Revalor-200 on day 70 had larger LM area resulting in lower calculated yield …