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Evaluation Of Forage Nutritive Value And Dry Matter Yield Of Stockpiled Tall Fescue Across Plant Hardiness Zones 7 And 8, Malerie Elizabeth Fancher Dec 2023

Evaluation Of Forage Nutritive Value And Dry Matter Yield Of Stockpiled Tall Fescue Across Plant Hardiness Zones 7 And 8, Malerie Elizabeth Fancher

Masters Theses

Pastures in Tennessee comprise mainly tall fescue [Schedonorus arundinaceus (Schreb.) Dumort.], a cool-season perennial grass. Tennessee producers feed hay for an average of 143 days per year, there is interest in utilizing stockpiling to extend the grazing season. Although this practice has been proven to reduce hay needs (Freeman et al., 2019), it is vital to maintain up-to-date recommendations using data from across the southeastern US to inform nutritional management decisions. The objective of this study is to determine the nutritive value and dry matter yield of stockpiled tall fescue across plant hardiness zones 7 and 8. Fourteen farms …


Assessing The Impact Of The Tennessee Equine Industry, Olivia Watson Dec 2023

Assessing The Impact Of The Tennessee Equine Industry, Olivia Watson

Masters Theses

The Tennessee equine industry is alive and prevalent across the entire state. However, due to the expansiveness of the industry, lack of consistent record keeping, and large discrepancies among reporting agencies, it has proven to be difficult to accurately account for the total impact of the industry in terms of population, demographics, and overall economic impact. The objective of this study was to 1) determine population demographics and economic impact of the equine industry in Tennessee and 2) determine the public perception on the addition of live equine racing within the state. An anonymous, online assessment was developed (March-August 2022; …


Assessing The Effects Of The Spring Hunting Season Start Date On Wild Turkey Seasonal Productivity And Hunter Behavior, Joseph Quehl Dec 2023

Assessing The Effects Of The Spring Hunting Season Start Date On Wild Turkey Seasonal Productivity And Hunter Behavior, Joseph Quehl

Masters Theses

Many states throughout the Southeast have documented declines in wild turkey (Meleagris gallopavo) harvest and estimates of recruitment in poult-per-hen ratios. Wild turkey populations are driven by seasonal productivity, so the decline in these parameters may indicate a decline in the overall population. One hypothesis as to why we are seeing a reduction in productivity and a potential population decline is that the spring hunting season is disrupting the reproductive cycle by harvesting too many males before they have had the opportunity to breed, or by harvesting dominant males and disrupting the social hierarchy of the flock. Our …


Pregnancy Influences On The Rumen Environment Of Angus Heifers Differing In Feed Efficiency, Miranda Gabrielle Martin Aug 2023

Pregnancy Influences On The Rumen Environment Of Angus Heifers Differing In Feed Efficiency, Miranda Gabrielle Martin

Masters Theses

With an expected increase in population by 2050, the demand for more animal protein will increase. To improve the sustainability of US cattle production, producers and researchers have historically focused on improving the feed efficiency of steers, producing a more marketable beef product. However, without a successful pregnancy, there would be no marketable animal to feed. The objective of this study was to examine the physiological changes that occur during pregnancy and their impact on the rumen microbial communities and the correlation to feed efficiency status in Angus heifers. Utilizing 17 cannulated Angus heifers, feed efficiency data was previously collected …


Management And Investment: Two Pillars Of Automatic Milking Systems Efficiency, Abby N. Mccalmon Aug 2023

Management And Investment: Two Pillars Of Automatic Milking Systems Efficiency, Abby N. Mccalmon

Masters Theses

Fetch cows, dairy cattle that do not voluntarily enter automated milking systems (AMS), increase labor costs, and decrease efficiency. The objective of this study was to describe fetch cows based on fetch lists and herd-management software data. This study was conducted on a commercial dairy farm (n = 510 cows) using 8 AMS from October 1, 2021, to May 10, 2022. Data were collected via PCDART, DairyComp, and a proprietary interface. Two fetch categories by cow, EverFetch (EF) and NeverFetch (NF), and three status groups by cow by day, True Fetch (on fetch list …


Using Novel Phenotypes To Understand And Predict Fertility In Beef Cows, Cassidy Catrett Aug 2023

Using Novel Phenotypes To Understand And Predict Fertility In Beef Cows, Cassidy Catrett

Masters Theses

Reproduction plays a major role in the production efficiency of livestock species. However, cow-centric reproductive traits are lowly heritable and are not expressed until later in an animal’s lifetime, making phenotypic selection ineffective at generating genetic gain. We can generate genetic progress by focusing selection on the genetic component of reproductive traits using Expected Progeny Differences (EPDs). We used the American Simmental Association’s performance and Total Herd Enrollment data, made up of 533,155 calving records from 303,158 females (132,403 cows and 170,755 heifers), 33,732 of which are genotyped, to develop two continuous and two discrete phenotypes focused on quantifying early …


Rumen Biogeographical Regions And Their Impact On Microbial And Metabolome Variation, Macey P. Soltis Dec 2022

Rumen Biogeographical Regions And Their Impact On Microbial And Metabolome Variation, Macey P. Soltis

Masters Theses

The rumen microbiome is a complex microbial network critical to the health and nutrition of its host, due to their inherent ability to convert low-quality feedstuffs into energy. In rumen microbiome studies, the ventral sac is sampled from due to ease of access and repeatability. However, anatomical musculature demarcates the rumen into five sacs which may support distinct microbial communities. The distinction among the microbes may generate functional variation among the rumen microbiome, thus, specialized tasks within different sacs. The objective of this study was to determine the rumen liquid metabolome and epimural, planktonic, and fiber-adherent bacterial communities among each …


Predicting Immunization Status At Arrival In Tennessee Stocker Calves, Claire E. Hunkler Dec 2022

Predicting Immunization Status At Arrival In Tennessee Stocker Calves, Claire E. Hunkler

Masters Theses

Bovine respiratory disease is a multifaceted disease with agent, host, and environmental factors. Stocker calves are at high risk of contracting the disease through many stressors like weaning, transportation, commingling, etc. The purpose of this project was to test if externally observed physical characteristics of calves on arrival at a stocker facility can be used to predict calfhood vaccination status determined based on antibody titer levels. Knowledge of highly correlated characteristics could allow stocker operators to reduce the occurrence of BRD through targeted management strategies, thus lowering morbidity, mortality, and treatment costs. Ear notches, blood, and visual characteristics were collected …


Staphylococcal Surface Proteins As Vaccine Candidates For The Control Of Staphylococcal Mastitis In Dairy Cows, Jessica Jean Vidlund Dec 2022

Staphylococcal Surface Proteins As Vaccine Candidates For The Control Of Staphylococcal Mastitis In Dairy Cows, Jessica Jean Vidlund

Masters Theses

Bovine mastitis, an inflammation of the mammary gland, is the single most costly disease of dairy cattle. Staphylococci, a major bacteria that cause bovine mastitis, are commonly divided into two major groups: Staphylococcus aureus and non-aureus staphylococci (NAS), previously known as coagulase-negative Staphylococcus species (CNS). Current mastitis control programs are not fully effective against staphylococcal mastitis and antibiotics are not sustainable due to limited success and the emergence of antimicrobial resistant bacteria. Non-antibiotic sustainable control tools, such as effective vaccines, are critically needed. Our lab developed and evaluated Staphylococcus aureus surface associated protein (SASP) and Staphylococcus chromogenes surface associated protein …


Optimal Stocker Production Strategies For Spring And Fall Calving Cow Herds, Cora Beth Key Aug 2022

Optimal Stocker Production Strategies For Spring And Fall Calving Cow Herds, Cora Beth Key

Masters Theses

This thesis consists of two chapters discussing the economics of raising stocker beef cattle in the southeast United States. The objective of the first chapter is to estimate supplemental feed cost for spring-calving cows, spring-born stockers, cows calving in the fall, and fall-born stockers, while considering the seasonality of forage production and nutritional needs. The chapter explores ways producers can lower their feed costs and demonstrates the importance of managing hay expenses for cattle producers to control cost. The objective of chapter two is to determine the profit-maximizing stocker period in an integrated cow-calf and stocker operation with both fall- …


Efficacy Of Sequential Estrus Synchronization And Timed Artificial Insemination In Beef Cattle Beginning 19 Days After An Initial Timed Artificial Insemination, Courtnie Carter Bridges Aug 2022

Efficacy Of Sequential Estrus Synchronization And Timed Artificial Insemination In Beef Cattle Beginning 19 Days After An Initial Timed Artificial Insemination, Courtnie Carter Bridges

Masters Theses

A breeding program utilizing single fixed-timed artificial insemination (AI) was compared to a resynchronization program for a second fixed-timed AI. Angus and Angus cross primiparous and multiparous cows were randomly assigned to one of two treatment regimens; either single TAI (CON; n=468) or two sequential TAI (RS; n=473). The main objectives were assessing pregnancy rates and analyzing fetal age to estimate calving distribution rates between the two treatment groups. The 7-day CO-synch + CIDR protocol was utilized in both treatment groups to synchronize estrus for TAI-1 at 60h - 66h post- Prostaglandin injection (PGf2α). Animals in the RS treatment groups …


Effects Of Protein Concentration And Beta-Adrenergic Agonists On Ruminal Microbial Communities In Finishing Beef Heifers, Alison P. Pfau May 2022

Effects Of Protein Concentration And Beta-Adrenergic Agonists On Ruminal Microbial Communities In Finishing Beef Heifers, Alison P. Pfau

Masters Theses

To improve animal performance and modify growth by increasing lean tissue accretion, beef cattle production has relied on use of growth promoting technologies such as beta-adrenergic agonists. These synthetic catecholamines, combined with the variable inclusion of rumen degradable (RDP) and undegradable protein (RUP), may improve feed efficiency and rate of gain in finishing beef cattle. However, research about the impact of beta-adrenergic agonists and protein level and source on the ruminal microbiome is limited. The objective of this study was to determine the effect of different protein concentrations and beta-adrenergic agonist (ractopamine hydrochloride; RAC usage) on ruminal bacterial communities in …


The Effect Of Bovine Endometrial Cell Conditioned Media On In Vitro Produced Bovine Embryo Development And Gene Expression, Mary A. Oliver Dec 2021

The Effect Of Bovine Endometrial Cell Conditioned Media On In Vitro Produced Bovine Embryo Development And Gene Expression, Mary A. Oliver

Masters Theses

In vitro produced (IVP) bovine embryos provide enhanced genetic value and a means for studying early embryonic development. However, IVP embryos are developmentally compromised and are lower quality compared to in vivo derived (IVD) embryos. Consequently, after transfer pregnancy rates from IVP embryos are consistently lower, as they exhibit the highest amounts of pregnancy failure during the early embryonic phase (prior to day 28). Progesterone (P4) has been shown to influence bovine endometrial epithelial (EPI) and stromal fibroblast (SF) cells to secrete developmentally important molecules that promote early embryo development and conceptus elongation. However, IVP embryos are not exposed to …


Nutritional Effects On Scrotal Circumference, Motility And Morphology Of Spermatozoa And Cytokine Concentrations Within Seminal Plasma Of Beef Cattle, Taylor D. Harrison Aug 2021

Nutritional Effects On Scrotal Circumference, Motility And Morphology Of Spermatozoa And Cytokine Concentrations Within Seminal Plasma Of Beef Cattle, Taylor D. Harrison

Masters Theses

Sire fertility is impacted by a wide variety of environmental and management conditions, potentially causing critical losses within beef operations. Nutrition is a main influence on the ejaculate due to bulls undergoing multiple planes of nutrition yearly. By identifying the effects of nutritional planes on the ejaculate composition, reproductive efficiency could be maximized at pregnancy establishment. We hypothesized periods of differing nutritional planes and body condition score (BCS) would affect bull fertility and cytokine concentrations within the ejaculate of bulls. Mature Angus bulls (n = 11) were individually housed and randomly assigned to one of two treatments: 1) …


Life History, Diet And Habitat Of The Federally Endangered Laurel Dace (Chrosomus Saylori), Shawna M. Fix May 2021

Life History, Diet And Habitat Of The Federally Endangered Laurel Dace (Chrosomus Saylori), Shawna M. Fix

Masters Theses

Laurel Dace (Chrosomus saylori) is a small, freshwater minnow that is endemic to headwater streams on Walden Ridge, Tennessee. The species was listed as federally endangered in 2011 and the U.S. Fish and Wildlife Service Recovery Plan indicates a need for life history, diet and habitat studies. A literature review, samples of archived specimens, and a surrogate species, the Tennessee Dace (Chrosomus tennesseensis), were used to describe the life history and diet of the Laurel Dace. A total of 370 Tennessee Dace were collected from Laurel Ford Branch, a stream 8.6 km from the Laurel Dace …


Predicting Voluntary Forage Intake Of Supplemented Beef Cattle, Connor Biehler Dec 2020

Predicting Voluntary Forage Intake Of Supplemented Beef Cattle, Connor Biehler

Masters Theses

A major priority of beef cattle production is to meet animal nutrient requirements in order to achieve a desired level of productivity. Accurately predicting voluntary forage intake (VFI) is necessary to accurately predict the total nutrient intake of grazing or forage-fed beef cattle that are also supplemented with other sources of nutrients. Therefore, the objectives of this experiment were to utilize data from published literature to 1) identify factors that explain variation in VFI, and 2) develop and validate one or more mathematical models that predict VFI or total nutrient intake of grazing or forage-fed and supplemented beef cattle. A …


Summer Foraging Range And Diurnal Roost Selection Of Tri-Colored Bats, Perimyotis Subflavus., Dustin Bradley Thames Dec 2020

Summer Foraging Range And Diurnal Roost Selection Of Tri-Colored Bats, Perimyotis Subflavus., Dustin Bradley Thames

Masters Theses

Tri-colored bat populations are declining in eastern North America where the fungal pathogen Pseudogymnoascus destructans has been introduced. The pathogen causes disease and mortality in cave hibernating bats. Once considered a common species in Tennessee, tri-colored bats are now being considered for protection under the Endangered Species Act. There is a paucity of research examining the basic ecology of tri-colored bats. Research to fill these knowledge gaps is needed to inform conservation plans and to define critical habitat. The first objective of my research was to characterize the summer diurnal roosts of tri-colored bats and to examine roost selection at …


Forage Species Selection For Transitional Organic Production In The Southeastern United States, Jonathan Kubesch Dec 2020

Forage Species Selection For Transitional Organic Production In The Southeastern United States, Jonathan Kubesch

Masters Theses

Despite the vast production markets for forage and organic products nationally, so far limited work has been done to develop organic forages specifically for Middle Tennessee or the mid-South in general. The present organic research field focuses on vegetable and grain production; however, forage production offers an easier transition for producers moving into certified organic agriculture. The present study seeks to evaluate several forage blends for optimizing forage production under low-input transitional organic conditions. Ideally a forage system could be tailored to the beef cattle operations of Middle Tennessee, the dominant forage consumption market in this region of the mid-South. …


Improving Body Composition In Broiler Chicks Through The Early Life Diet, Kamille Piacquadio Aug 2020

Improving Body Composition In Broiler Chicks Through The Early Life Diet, Kamille Piacquadio

Masters Theses

The poultry industry relies heavily on the efficient growth performance of broilers to provide quality breast meat at a low cost to meet consumer demand. However, high efficiency of broilers is also related to the occurrence and severity of skeletal muscle abnormalities like wooden breast. This study investigated the efficacy of incorporating long-chain omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), into the diets of hens and their offspring on altering the causative features of wooden breast. Early exposure to these fatty acids in broilers has shown to reduce adiposity, and may address excess adipogenesis seen in …


Effects Of A Moderate And Aggressive Implant Strategy On The Rumen Microbial Community And Metabolome In Steers, Madison Henniger Aug 2020

Effects Of A Moderate And Aggressive Implant Strategy On The Rumen Microbial Community And Metabolome In Steers, Madison Henniger

Masters Theses

The effects of growth-promoting implants have been well-defined for their ability to impact growth in beef cattle. Production-relevant microbiomes in the rumen have also been associated with growth traits. However, the role of implant strategies on the rumen microbiome is not understood. The objective was to determine if varying doses of implant hormones cause gain-associated ruminal microbial community shifts. To assess this, a completely randomized design was used and 336 fall-born steers between 450-470 days of age from the germplasm evaluation population at the US Meat Animal Research Center (Clay Center, NE) were divided into two treatment groups: 1) a …


Bat Population Status And Roost Selection Of Tri-Colored Bats In The Great Smoky Mountains National Park In The Era Of White-Nose Syndrome, Grace Marie Carpenter Dec 2017

Bat Population Status And Roost Selection Of Tri-Colored Bats In The Great Smoky Mountains National Park In The Era Of White-Nose Syndrome, Grace Marie Carpenter

Masters Theses

The ongoing spread of white-nose syndrome is causing devastating declines range-wide for certain North American bat species. Baseline population data that would help mangers monitor bat populations in the face of WNS is lacking. Likewise, knowledge of summer roosts, a limiting resource for tri-colored bats (Perimyotis subflavus), a species threatened by WNS, is lacking in the southern portion of their range. In our study, we investigated the effect that WNS has had on a population of tricolored bats in the Great Smoky Mountains National Park, TN-NC. We also characterized summer roosts for the species at the microhabitat and …


Coping With Drought In Beef Cattle Production: Innovation Through Optimal Warm-Season Forage Systems, Katelynn Elizabeth Zechiel Dec 2017

Coping With Drought In Beef Cattle Production: Innovation Through Optimal Warm-Season Forage Systems, Katelynn Elizabeth Zechiel

Masters Theses

Drought conditions have had detrimental effects on beef cattle production in the southeastern states where forages are the primary source of feed for livestock. Many southeastern states lie within the fescue-belt, where tall fescue is the predominant livestock forage. Tall fescue is a cool-season (CS) grass that thrives in the cooler temperatures of spring and fall, becoming semi-dormant during peak summer temperatures and again in winter. Conversely, warm-season (WS) forage species increase in production during the summer months and exhibit drought tolerant qualities, making them a viable summer forage option to complement tall fescue for beef cattle producers. The primary …


Surveillance Of Ticks Parasitizing Tennessee Beef Cattle And Investigations Into The Microbial Communities Of Cattle Associated And Questing Amblyomma Maculatum, David Paul Theuret Dec 2017

Surveillance Of Ticks Parasitizing Tennessee Beef Cattle And Investigations Into The Microbial Communities Of Cattle Associated And Questing Amblyomma Maculatum, David Paul Theuret

Masters Theses

Despite the risks that ticks and tick-borne disease pose to the beef cattle industry, many Tennessee producers are unaware of the dangers they represent. This mindset could facilitate the invasion and establishment of exotic ticks and pathogens that would devastate the cattle industry. Current control practices rely on chemical methods, which are not effective long-term; therefore, investigations into creating an integrated approach to control would create more sustainable methods. This study aims to address this through two objectives: The first is to determine the species composition, seasonal prevalence, geographic distribution and diversity of ticks on Tennessee cattle. The second is …


Relationship Of Observed Parlor Practices And Producer Attitudes With Bulk Tank Somatic Cell Counts In The Southeast Usa, Chandler Lauren Moats Blakely May 2017

Relationship Of Observed Parlor Practices And Producer Attitudes With Bulk Tank Somatic Cell Counts In The Southeast Usa, Chandler Lauren Moats Blakely

Masters Theses

Inflammation of the mammary gland is indicated by a rise in somatic cell count (SCC) and impacts milk quality. The Southeast (SE) USA has a higher proportion of herds with elevated SCC compared to other USA regions. The SE also has the least information available about parlor procedures. The goals of this thesis are to explore the level of implementation of parlor procedures, determine which practices promote low SCC in Southeast USA dairy herds and investigate the association of attitude towards parlor management methods with BTSCC.

In chapter I, researchers performed on-farm assessments in Kentucky, Mississippi, Tennessee, and Virginia. The …


Utilizing Pregnancy Associated Glycoproteins To Improve Reproductive Efficiency In Cattle, Sydney Taylor Reese May 2017

Utilizing Pregnancy Associated Glycoproteins To Improve Reproductive Efficiency In Cattle, Sydney Taylor Reese

Masters Theses

Diagnosing and maintaining successful pregnancies are one of the most important components to profitable and efficient management of beef and dairy cattle operations. Pregnancy loss is a major component of reproductive inefficiency and has been investigated less intensively in beef cattle than in dairy cattle. Pregnancy Associate Glycoproteins [PAGs] are placental products which have been identified as an accurate tool for pregnancy diagnosis and as substantial evidence indicates, markers of embryo and placental competence. The aim of these two studies is to further distinguish characteristics of pregnancies based on PAG concentration. Serial embryo transfer was used in beef heifers to …


Effect Of Varying Rumen Degradable And Undegradable Protein On Milk Production And Nitrogen Efficiency In Lactating Dairy Cows Under Summer Conditions, Jeffrey D. Kaufman Dec 2016

Effect Of Varying Rumen Degradable And Undegradable Protein On Milk Production And Nitrogen Efficiency In Lactating Dairy Cows Under Summer Conditions, Jeffrey D. Kaufman

Masters Theses

The objective is to determine the effect of reducing nitrogen input through feeding low rumen degradable protein (RDP) and rumen undegradable protein (RUP) proportions on milk production, nitrogen efficiency and metabolism in heat-stressed cows. Forty-eight mid-lactating, Holstein cows were assigned to treatments using a randomized block design in a 2x2 factorial arrangement of treatments (n = 12/treatment). Treatments included two levels of RDP (10 and 8%) and two levels of RUP (8 and 6%). From d 1 to 21, a common diet (10% RDP-8% RUP) was fed to cows followed with their respective treatment diets fed from d 22 to …


Effect Of Omega-3 Polyunsaturated Fatty Acid (N-3 Pufa) Supplementation To Lactating Sows On Growth And Indicators Of Stress In The Post-Weaned Pig, John M. Mcafee Dec 2016

Effect Of Omega-3 Polyunsaturated Fatty Acid (N-3 Pufa) Supplementation To Lactating Sows On Growth And Indicators Of Stress In The Post-Weaned Pig, John M. Mcafee

Masters Theses

The first experiment was designed to determine the concentration of protected fish oil product (PFO), as GromegaTM, to be added that would sufficiently decrease the polyunsaturated fatty acid (PUFA) ratio in the sows’ milk and colostrum. Of the 3 diets tested (0.25%, 0.5% and 1%) with a control (0% PFO), only the 1% PFO diet had an effect on the PUFA concentrations. The docosahexaenoic acid (DHA) concentration tended (P = 0.05) to be greater in the 1% PFO diet for both colostrum and milk samples. A second experiment was designed to …


Follicular Dynamics In Insulin Resistant Mares, Julio Cesar Prado Dec 2016

Follicular Dynamics In Insulin Resistant Mares, Julio Cesar Prado

Masters Theses

Obesity and insulin resistance have been linked to prolonged interovulatory period, aberrations in the estrous cycle, and continuous reproductive activity during the non-breeding season. EMS has been determined to influence the intrafollicular environment of mare ovaries. In humans, insulin resistance has been linked to polycystic ovaries as part of Polycystic Ovarian Syndrome (PCOS). A study was conducted to determine 1) the impact of insulin resistance on follicle growth and size at ovulation, and 2) whether predicted ovulatory follicles respond to hCG administration in Insulin-resistant (IR) mares. Mares were selected for the study based on insulin sensitivity and separated into an …


The Effect Of Heat Stress And Essential Amino Acids On Production And Metabolism Of Lactating Dairy Cattle, Kimberly Rose Kassube Aug 2016

The Effect Of Heat Stress And Essential Amino Acids On Production And Metabolism Of Lactating Dairy Cattle, Kimberly Rose Kassube

Masters Theses

Heat stress (HS) causes decreases in production of lactating cattle that is only partially explained by decreases in intake. Evidence suggests that changes in energy and protein metabolism occur to cope with the impact of HS. The objective of this thesis was to determine if the effect of jugular infusion of essential amino acids (AA) ameliorated the negative effects of HS in milk production and metabolism. Twelve multiparous lactating Holstein cows were used in a crossover design to evaluate the effect of thermoneutral (THN) and HS environments along with the absence (CTL) …


Association Of Genotype At Drd2 With Growth And Reproductive Performance Traits In Bulls Grazing Toxic Endophyte-Infected Tall Fescue, Kaysie Jennings Aug 2016

Association Of Genotype At Drd2 With Growth And Reproductive Performance Traits In Bulls Grazing Toxic Endophyte-Infected Tall Fescue, Kaysie Jennings

Masters Theses

Fescue toxicosis can negatively impact growth and fertility of beef cattle grazing tall fescue infected with an endophytic fungus. The fungus produces ergot alkaloids that contribute to the hardiness of the plant, but can be detrimental to the animal if consumed. A single nucleotide polymorphism (SNP) in the dopamine receptor D2 gene (DRD2) has been associated with serum prolactin concentrations and hair coat scores in cattle grazing toxic endophyte-infected (TE) tall fescue; cattle with the GG genotype had decreased serum prolactin concentrations and increased hair coat scores. Separately, heifers with the AA genotype calved sooner than AG or GG heifers. …